Power Max PM User manual

P/N 472642 Rev B - 09/11/08
WARNING
If the information in this manual is not
followed exactly, a fire or explosion may
result causing property damage, personal
injury or loss of life.
Do not store or use gasoline or other
flammable vapors and liquids in the vicinity
of this or any other appliance.
WHAT TO DO IF YOU SMELL GAS
• Do not try to light any appliance.
• Do not touch any electrical switch; do not
use any phone in your building.
• Immediately call your gas supplier from a
nearby phone. Follow the gas supplier's
instructions.
• If you cannot reach your gas supplier, call
the fire department.
Installation and service must be performed by
a qualified installer, service agency, or gas
supplier.
FOR YOUR SAFETY: This product must be installed and serviced by a
professional service technician, qualified in hot water boiler installation
and maintenance. Improper installation and/or operation could create
carbon monoxide gas in flue gases which could cause serious injury,
property damage, or death. Improper installation and/or operation will
void the warranty.
AVERTISSEMENT
Assurez-vous de bien suivres les instructions
données dans cette notice pour réduire au
minimum le risque d’incendie ou d’explosion ou
pour éviter tout dommage matériel, toute
blessure ou la mort.
Ne pas entreposer ni utiliser d’essence ni
d’autres vapeurs ou liquides inflammables dans
le voisinage de cet appareil ou de tout autre
appareil.
QUE FAIRE SI VOUS SENTEZ UNE ODEUR DE GAZ:
• Ne pas tenter d’allumer d’appareils.
• Ne touchez à aucun interrupteur. Ne pas vous
servir des téléphones dansle bâtiment où vous
vous trouvez.
• Appelez immédiatement votre fournisseur de
gaz depuis un voisin. Suivez les instructions
du fournisseur.
• Si vous ne pouvez rejoindre le fournisseur de
gaz, appelez le sservice des incendies.
L’installation et l’entretien doivent être assurés par
un installateur ou un service d’entretien qualifié ou
par le fournisseur de gaz.
IMPORTANT SAFETY INSTRUCTIONS
READ AND FOLLOW ALL INSTRUCTIONS
SAVE THESE INSTRUCTIONS
U.S. Reg. 2,765,423
®
Installation and Operation
Instructions for
Pool Heater
Model PM
PowerMax
TM

Pentair Water Commercial Pool and Aquatics
Page 2
SECTION 1.
General Information
1.1 Introduction ....................................................... 3
1.2 Model Identification ........................................... 3
1.3 Warranty ........................................................... 4
1.4 Dimensions ....................................................... 4
1.5 Locating the Appliance ..................................... 4
1.6 Locating Heater with Respect to Pool
System Loop ..................................................... 6
1.7 Locating Appliance for Correct Horizontal Vent/
Ducted Air Distance From Outside Wall ........... 6
SECTION 2.
Venting and Combustion Air
2.1 Combustion Air ................................................. 6
2.1.1 Combustion Air From Room ............................. 6
2.1.2 Intake Combustion Air ...................................... 7
2.2 Venting ............................................................. 7
2.2.1 Vent Categories ................................................ 7
2.2.2 Category I Vent ................................................. 8
2.2.3 Common Venting Systems ............................... 8
2.2.4 Category III Vent ............................................... 8
2.3 Locating Vent & Combustion Air Terminals ...... 9
2.3.1 Side Wall Vent Terminal ................................... 9
2.3.2 Side Wall Combustion Air Terminal ................ 10
2.3.3 Vertical Vent Terminal .................................... 10
2.3.4 Vertical Combustion Air Terminal ................... 10
2.4 Vent Terminals for Outdoor Units ................... 10
SECTION 3.
Gas Supply and Piping
3.1 Gas Supply and Piping ................................... 10
SECTION 4A.
Water Connections
4.2 Automatic Chlorinators ................................... 11
4.3 Sensor Locations ............................................ 12
SECTION 5.
Electrical Connections
5.1 Main Power ..................................................... 13
5.2 Temperature (Operating) Control ................... 13
5.3 Programming the Temperature Control .......... 13
5.3.1 Temperature Control Overview ....................... 13
5.3.2 Programming Control Parameters .................. 13
5.3.3 Setpoint - LSP................................................. 14
5.3.4 Differential - dLS ............................................. 14
5.3.5 Pump Operation ............................................. 14
5.3.6 Heater Purge (Pump Delay) - PD ................... 14
5.4 Limit Controls .................................................. 14
SECTION 6.
Operating Instructions
6.1 Sequence of Operation ................................... 14
6.2 Filling the Heater System ................................ 15
6.3 Operating the Burner and Set Up ................... 15
6.3.1 Set Up for 0 to 2500 Feet Altitude................... 15
6.3.2 High Altitude Adjustment and Set Up.............. 16
6.4 Shutting Down the PowerMax ........................ 16
6.5 Spring and Fall Operation
Stand-by Service ............................................ 16
6.6 Winter Operation ............................................ 16
6.7 To Restart the PowerMax ............................... 17
6.8 Therapeutic Pools (Spas) ............................... 17
SECTION 7.
Maintenance
7.1 System Maintenance ...................................... 17
7.2 Appliance Maintenance and
Component Description .................................. 18
7.2.1 Burners ........................................................... 18
7.2.2 Filter ................................................................ 18
7.2.3 Gas Valves ..................................................... 18
7.2.4 Pool Loop High Limit Control .......................... 18
7.2.5 Automatic Reset High Limit Control ................ 18
7.2.6 Temperature Control ...................................... 18
7.2.7 Ignition Controls .............................................. 18
7.2.8 Ignitors ............................................................ 19
7.2.9 Ignition Sensors .............................................. 19
7.2.10 Transformer .................................................. 19
7.2.11 Blowers ........................................................ 19
7.2.12 Flow Switch .................................................. 19
7.2.13 Heat Exchanger Coil .................................... 19
SECTION 8.
Trouble Shooting
8.1 Resolving Lockouts ........................................ 20
8.2 Delayed Ignition – Possible Causes ............... 20
8.3 Short Cycling .................................................. 20
8.4 High Gas Consumption .................................. 20
8.5 Troubleshooting the Pool Heater
Temperature Control ...................................... 21
8.6 Troubleshooting PowerMax Controls .............. 21
SECTION 9.
Replacement Parts
9.1 General Information ........................................ 22
9.2 Parts List ......................................................... 22
Pentair Technical Support ....................... 35
TABLE OF CONTENTS

PowerMax Pool Heater Page 3
SECTION 1.
General Information
In the Commonwealth of Massachusetts, this
appliance must be installed by a licensed plumber or
gas fitter.
WARNING
The PowerMax pool heater must be installed in
accordance with the procedures detailed in this
manual, or the warranty may be voided. The
installation must conform to the requirements of the
local jurisdiction having authority, and, in the United
States, to the latest edition of the National Fuel Gas
Code, ANSI Z223.1/NFPA54. In Canada, the
installation must conform to the latest edition of
CAN/CGA-B149.1, Natural Gas Installation Code or
CAN/CGA-B149.2, Propane Gas Installation Code,
and/or local codes. Where required by the authority
having jurisdiction, the installation of PowerMax
appliances must conform to the Standard for
Controls and Safety Devices for Automatically Fired
Boilers, ANSI/ASME CSD-1. Any modifications to
the boiler, its gas controls, or wiring may void the
warranty. If field conditions require modifications,
consult the factory representative before initiating
such modifications.
1.1 Introduction
This manual provides information necessary for
the installation, operation, and maintenance of
PowerMax copper tube pool heaters. Read it carefully
before installation.
All application and installation procedures
should be reviewed completely before proceeding with
the installation. Consult Pentair Technical Support
(sse page 2), or your local sales representative, with
any issues or questions regarding this equipment.
Experience has shown that most operating issues are
caused by improper installation.
The PowerMax appliance is protected against
over pressurization. A pressure relief valve is fitted to
all appliances. It is installed on the outlet header, at
the water outlet of the appliance.
IMPORTANT: The inlet gas pressure to the appliance
must not exceed 13" W.C. (3.2kPa).
All installations must be made in accordance
with the 1). American National Standard Z223.1/
NFPA54-Latest Edition “National Fuel Gas Code” or
2). CAN/CGA 1-B149 “Installation Codes for Gas
Burning Appliances and Equipment” and with the
requirement of the local utility or other authorities
having jurisdiction. Such applicable requirements take
precedence over the general instructions contained
herein.
All electrical wiring is to be done in accordance
with the local codes, or in the absence of local codes,
with: 1). The National Electrical Code ANSI/NFPA
No. 70-latest Edition, or 2). CSA STD. C22.1
“Canadian Electrical Code - Part 1”. This appliance
must be electrically grounded in accordance with these
codes.
1.2 Model Identification
Consult the rating plate on the unit. The
following information describes the model number
structure.
Model Character Designation
1-2 Model Series Designation
P M = PowerMax
3 Usage
P = Pool Heater
4-7 Size
0 5 0 0 = 500,000 BTU/h input
0 7 5 0 = 750,000 BTU/h input
1 0 0 0 = 999,000 BTU/h input
1 2 5 0 = 1,250,000 BTU/h input
1 5 0 0 = 1,500,000 BTU/h input
1 7 5 0 = 1,750,000 BTU/h input
2 0 0 0 = 1,999,000 BTU/h input
8 Fuel
N = Natural Gas
P = Liquid Propane
9 Altitude
A = 0-10,000 feet
10 Location
C = Indoor and Outdoor
11 Firing Mode
C = On-off
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
P M P A C C 2 N
SERIES
PM
USAGE
P
SIZE
0500
0750
1000
1250
1500
1750
2000
FUEL
N
P
ALTITUDE
A
FIRING
MODE
C(ON/OFF)
LOCATION
C
REVISION
2
HEAT
EXCHANGER
B
C
K
N
P
S
OPTIONS
CODE
X
J
L
PUMP
OPTIONS
N

Pentair Water Commercial Pool and Aquatics
Page 4
13 Revision
2 = Second version
14 Heat Exchanger
B = Glass-lined CI / copper / brz trim (std. PM)
K = Bronze / copper
P = Glass-lined cast iron / cu-nickel / brz trim
S = Bronze / cu-nickel
15 Option Code
X = Standard unit
J = CSD-1, FM, IRI, IL
L = MN and LDS (Indoor units only)
16 Pump Options
N = Pump mounted, normal pump
1.3 Warranty
PowerMax appliances are covered by a limited
warranty. The owner should fill out the warranty
registration card and return it to Pentair Water
Commercial Pool and Spa.
All warranty claims must be made to an
authorized Pentair Water Commercial Pool and Spa
epresentative or directly to the factory. Claims must
include the serial number and model (this information
can be found on the rating plate), installation date, and
name of the installer. Shipping costs are not included
in the warranty coverage.
Some accessory items are shipped in separate
packages. Verify receipt of all packages listed on the
packing slip. Inspect everything for damage
immediately upon delivery, and advise the carrier of
any shortages or damage. Any such claims should be
filed with the carrier. The carrier, not the shipper, is
responsible for shortages and damage to the shipment
whether visible or concealed.
1.4 Dimensions
(See Figure 1.)
1.5 Locating the Appliance
The appliance should be located to provide
clearances on all sides for maintenance and inspection.
It should not be located in an area where leakage of
any connections will result in damage to the area
adjacent to the appliance or to lower floors of the
structure.
When such a location is not available, it is
recommended that a suitable drain pan, adequately
drained, be installed under the appliance.
The appliance is design certified by CSA-
International for installation on combustible flooring;
in basements; in closets, utility rooms or alcoves. The
location for the appliance should be chosen with
regard to the vent pipe lengths and external plumbing.
The unit shall be installed such that the gas ignition
system components are protected from water
(dripping, spraying, rain, etc.) during operation and
service (circulator replacement, control replacement,
etc.). When vented vertically, the PowerMax must be
located as close as practical to a chimney or outside
wall. If the vent terminal and/or combustion air
terminal terminate through a wall, and there is
potential for snow accumulation in the local area, both
terminals should be installed at an appropriate level
above grade.
Horizontal Air Collar
Heater Vent Collar Vent Pipe & Pipe Max. Pipe Max. No. Side Wall Side Wall
Size Size Diameter* Diameter Length of Elbows Vent Combustion
Terminal Air Terminal
in. cm in. cm in cm ft. m Part Number Part Number
500 8 20 6 15 6 15 50 15 3 CA001401 20260701
750 10 25 8 20 6 15 50 15 3 CA001402 20260701
1000 10 25 8 20 8 20 50 15 3 CA001402 20260703
1250 12 30 8 20 8 20 50 15 3 CA001403 20260703
1500 12 30 8 20 8 20 50 15 3 CA001403 20260703
1750 14 36 8 20 8 20 50 15 3 CA001405 20260703
2000 14 36 12 30 12 30 50 15 3 CA001404 20260706
*Horizontal venting requires stainless vent pipe. See Table 5.
Table 1. Horizontal Vent / Combustion Air Parameters.

PowerMax Pool Heater Page 5
Figure 1. Dimensional Data.
Air Vent Horiz.
Conn. Conn. Vent
Size A B C D E F G H W* V* Pipe
500 33½ 85 15¾ 40 5¾ 15 29¾ 76 32¾ 83 7¾ 20 8¾ 22 46 117 6 15 8 20 6 15
750 45½ 116 21¾ 55 5¾ 15 29¾ 76 32¾ 83 7¾ 20 8¾ 22 58 147 6 15 10 25 8 20
1000 57½ 146 28¾ 73 5¾ 15 29¾ 76 32¾ 83 7¾ 20 7 18 70 178 8 20 10 25 8 20
1250 68 172 34 86 101/8 26 30¾ 78 29½ 75 8¾ 22 8¾ 22 80 203 8 20 12 30 8 20
1500 78½ 199 39¾ 101 101/8 26 30¾ 78 29½ 75 8¾ 22 8¾ 22 91 231 8 20 12 30 8 20
1750 89 226 44½ 113 101/8 26 30¾ 78 29½ 75 8¾ 22 8¾ 22 101 256 8 20 14 36 8 20
2000 99½ 253 49¾ 126 101/8 26 30¾ 78 29½ 75 8¾ 22 8¾ 22 112 284 12 30 14 36 12 30
*Air and vent connections may be on top or back of the PowerMax, and are field convertible. Dimensions in inches cm .
Shipping Weight
Size lbs. kg
500 480 218
750 560 254
1000 670 304
1250 730 331
1500 815 370
1750 880 400
Dimensions shown in
inches cm

Pentair Water Commercial Pool and Aquatics
Page 6
The dimensions and requirements that are shown
in Table 2 should be met when choosing the locations
for the appliance:
Required Recommended
Appliance Clearance From Service Access
Surface Combustible Material Clearance
inches cm inches cm
Left Side 1 2.5 24 61
Right Side 1 2.5 24 61
Top 1 2.5 12 30
Back 1 2.5 **12** 30**
Front 1 2.5 36 91
Vertical
(Category 1) 6*
15.2*
Vent
Horizontal per UL1738 venting
(Category 3) system supplier’s
Vent instructions
*1" (2.5cm) when b-vent is used.
**When vent and/or combustion air connects to the back,
recommended clearance is 36" (91cm).
Table 2. Clearances.
1.6 Locating Heater with Respect to Pool
System Loop
For the best results, the PowerMax should be
located within 15 feet (4.6m) of the pool system loop.
The pump is sized for 30 feet (9.1m) of piping.
If the appliance must be installed with longer
piping runs, then larger diameter piping shall be used.
Consult the factory for assistance.
1.7 Locating Appliance for Correct
Horizontal Vent/Ducted Air Distance
From Outside Wall
The forced draft combustion air blower/blowers
in the appliance has/have sufficient power to pull air
and vent properly when the following guidelines for
horizontal air and vent are followed (see Table 1).
NOTE: On models 750-2000, the vent collar size is
larger than the size of the vent pipe that can be used.
Side wall vent terminals for these sizes are shipped
with replacement vent collars, to accommodate
horizontal vent sizes. Vent collar size and horizontal
pipe diameters can be found in Table 1. The larger
vent collar size is to accommodate Category I
(vertical) vent systems.
NOTE: When located on the same wall, the PowerMax
combustion air intake terminal must be installed a
minimum of 12" (30cm) below the exhaust vent
terminal and separated by a minimum of 36 inches
(91cm) horizontally.
The air intake terminal must be installed high
enough to avoid blockage from snow, leaves and other
debris. Never obtain combustion air from the pool
area. Corrosion of and/or damage to the pool heater
may result.
SECTION 2.
Venting and Combustion Air
2.1 Combustion Air
PowerMax pool heaters must have provisions for
combustion and ventilation air in accordance with
section 5.3, Air for Combustion and Ventilation, of the
National Fuel Gas Code, ANSI Z223.1, or Sections
7.2, 7.3 or 7.4 of CAN/CGA B149, Installation Codes,
or applicable provisions of the local building codes.
A PowerMax appliance may receive combustion
air from the space in which it is installed, or it can be
ducted directly to the unit from the outside.
Ventilation air must be provided in either case. Never
obtain combustion air from the pool area. Corrosion of
and/or damage to the pool heater may result.
2.1.1 Combustion Air From Room
In the United States, the most common
requirements specify that the space shall communicate
with the outdoors in accordance with method 1 or 2,
which follow. Where ducts are used, they shall be of
the same cross-sectional area as the free area of the
openings to which they connect.
Method 1: Two permanent openings, one
commencing within 12 inches (30 cm) of the top and
one commencing within 12 inches (30 cm) of the
bottom, of the enclosure shall be provided. The
openings shall communicate directly, or by ducts, with
the outdoors or spaces that freely communicate with
the outdoors. When directly communicating with the
outdoors, or when communicating to the outdoors
through vertical ducts, each opening shall have a
minimum free area of 1 square inch per 4000 Btu/hr
(5.5 square cm/kW) of total input rating of all
equipment in the enclosure. When communicating to
the outdoors through horizontal ducts, each opening
shall have a minimum free area of not less than
1 square inch per 2000 Btu/hr (11 square cm/kW) of
total input rating of all equipment in the enclosure.
Table 3 shows data for this sizing method, for each
PowerMax model.
Method 2: One permanent opening,
commencing within 12 inches (30 cm) of the top of
the enclosure, shall be permitted. The opening shall
directly communicate with the outdoors or shall
communicate through a vertical or horizontal duct to
the outdoors or spaces that directly communicate with
the outdoors and shall have a minimum free area of
1 square inch per 3000 Btu/hr (7 square cm/kW) of the

PowerMax Pool Heater Page 7
total input rating of all equipment located in the
enclosure. This opening must not be less than the sum
of the areas of all vent connectors in the confined
space.
Other methods of introducing combustion and
ventilation air are acceptable, providing they conform
to the requirements in the applicable codes listed
above.
In Canada, consult local building and safety
codes or, in absence of such requirements, follow
CAN/CGA B149.
Boiler Each Opening*
Model Square inches Square cm
500 125 807
750 188 1213
1000 250 1613
1250 313 2020
1500 375 2420
1750 438 2826
2000 500 3226
*Net Free Area in Square Inches / Square cm
Area indicated is for one of two openings; one at floor
level and one at the ceiling, so the total net free area
could be double the figures indicated.
This chart is for use when communicating directly with the
outdoors. For special conditions and alternate methods,
refer to the latest edition of ANSI Z223.1.
Note: Check with louver manufacturers for net free area
of louvers. Correct for screen resistance to the net free
area if a screen is installed. Check all local codes
applicable to combustion air.
Table 3. Combustion Air Openings.
2.1.2 Intake Combustion Air
Never obtain combustion air from the pool area.
Corrosion of and/or damage to the pool heater may
result. The combustion air can be taken through the
wall, or through the roof. When taken from the wall, it
must be taken from out-of-doors by means of the
horizontal wall terminal (see Table 2). When taken
from the roof, a field-supplied rain cap or an elbow
arrangement must be used to prevent entry of rain
water (see Figure 2).
Use single-wall galvanized pipe, per table 4,
for the combustion air intake (see Table 1 for
appropriate size). Route the intake to the heater as
directly as possible. Seal all joints with tape. Provide
adequate hangers. The unit must not support the
weight of the combustion air intake pipe. Maximum
linear pipe length allowed is 50 feet (15.2m). Three
elbows have been calculated into the 50-foot (15.2m)
linear run. Subtract 10 allowable linear feet (3.0m) for
every additional elbow used (see Table 1). When
fewer than 3 elbows are used, the maximum linear
pipe length allowed is still 50 feet (15.2m).
Term Description
Pipe Single-wall galvanized steel pipe, 24 gauge
minimum (either insulated or non-insulated)
Joint Permanent duct tape or aluminum tape
Sealing
Table 4. Required Combustion Air Piping Material.
The connection for the intake air pipe is on the
filter box. The PowerMax appliances may have
venting and combustion air ducting attached to the top
or the back. They are shipped with the connections at
the top. For attaching either or both pipes to the back,
the mounting flanges are reversible by removing the
mounting screws and orienting the flanges in the
desired position. Replace the screws after positioning
flanges. Run a bead of silicone around the collar and
slide the pipe over the collar. Secure with sheet metal
screws.
In addition to air needed for combustion, air shall
also be supplied for ventilation, including all air
required for comfort and proper working conditions
for personnel. The PowerMax loses less than 1 percent
of its input rating to the room, but other heat sources
may be present.
2.2 Venting
2.2.1 Vent Categories
Depending upon desired PowerMax venting, it
may be considered a Category I or a Category III
appliance. In general, a vertical vent system will be a
Category I system. However, in rare instances, a
heater's vertical vent system may be considered
Category III. In the U.S., the National Fuel Gas Code
(American National Standard Z223.1-Latest Edition),
or in Canada the CSA B149.1 (latest edition), defines
Figure 2. Combustion Air and Vent Through Roof.

Pentair Water Commercial Pool and Aquatics
Page 8
a Category I vent system, and includes rules and tables
to size these vent systems. If the heater’s vertical vent
system does not satisfy the criteria for Category I
venting, it must be vented as a Category III system.
All PowerMax vent systems which discharge
horizontally (without the use of a power venter) are
considered Category III vent systems.
2.2.2 Category I Vent
When vented as a category I appliance, the vent
system must conform to the National Fuel Gas Code
(American National Standard Z223.1-Latest Edition)
in the U.S., or in Canada, to CSA B149.1 (latest
edition). The vent system must be sized and installed
for a Category I Fan-Assisted Appliance.
If chimney height is greater than 25 feet, or if
multiple units are vented into the same vertical vent, a
barometric damper must be installed on each
appliance, such that the flue draft does not exceed
(negative) 0.1" w.c.
If using a power venter for any type of Category
I venting, the draft should be set between (negative)
0.01 and 0.10" w.c.
2.2.3 Common Venting Systems
PowerMax units are Category I fan-assisted
when vented vertically and adhering to all applicable
codes. PowerMax units are not allowed to be vented
into a common horizontal vent system, unless a
properly-sized vent fan is used, and the common vent
system is properly designed by the vent fan
manufacturer or a qualified engineer. When common
venting PowerMax fan-assisted heaters with other
appliances through one shared vertical duct called a
“common vent”, special care must be taken by the
installer to ensure safe operation. In the event that the
common vent is blocked, it is possible, especially for
fan-assisted devices, to vent backwards through non-
operating appliances sharing the vent, allowing
combustion products to infiltrate occupied spaces. If
the appliances are allowed to operate in this
condition, serious injury or death may occur.
WARNING
Operation of appliances with a blocked common
vent may lead to serious injury or death. Safety
devices must be implemented to prevent blocked
common vent operation. If safe operation of all
appliances connected to a common vent cannot be
assured, including prevention of spillage of flue
gasses into living spaces, common venting should
not be applied, and appliances should each be
vented separately.
It is for this reason that, in addition to following
proper vent sizing, construction and safety
requirements from the National Fuel Gas Code, ANSI
Z223.1 or in Canada, from CSA B149.1 as well as all
applicable local codes, it is required that installers
provide some means to prevent operation with a
blocked common vent. It is suggested that a blocked
vent safety system be employed such that if the switch
from one appliance trips due to excessive stack spill or
backpressure indicating a blocked vent condition, that
all appliances attached to the vent be locked out and
prevented from operating. (Note that the PowerMax
pool heater is equipped with a blocked vent safety
(pressure) switch, as shipped.) As an additional
precaution, it is recommended that a Carbon
Monoxide (CO) alarm be installed in all enclosed
spaces containing combustion appliances. If assistance
is required in determining how a blocked vent safety
system should be connected to a this product, please
call [phone].
Refer to the installation and operating
instructions on all appliances to be common vented for
instructions, warnings, restrictions and safety
requirements. If safe operation of all appliances
connected to a common vent cannot be assured,
including prevention of spillage of flue gasses into
living spaces, common venting should not be applied,
and appliances should each be vented separately.
2.2.4 Category III Vent
When the PowerMax is vented with horizontal
discharge, it must be installed per this installation
manual and the venting system manufacturer’s
installation instructions. The vent system must be
sealed stainless steel, per table 5.
Route the vent pipe to the heater as directly as
possible. Seal all joints and provide adequate hangers
as required in the venting system manufacturer’s
Installation Instructions. Horizontal portions of the
venting system must be supported to prevent sagging
and may not have any low sections that could trap
condensate. The unit must not support the weight of
the vent pipe. Horizontal runs must slope downwards
not less than ¼ inch per foot (2 cm/m) from the unit to
the vent terminal. Reference Table 2 for the size of the
Category III vent system. Up to three elbows can be
used with 50 linear feet (15.2m) of pipe. Subtract 10
allowable linear feet (3.0m) for every additional elbow
used.
Term Description
Pipe Must comply with UL Standard 1738
such as Type 29-4C Stainless Steel
(either insulated or non-insulated).
Joint Follow vent manufacturer’s instructions
Sealing
Table 5. Required Horizontal Venting Material.
2.3 Locating Vent & Combustion Air
Terminals

PowerMax Pool Heater Page 9
2.3.1 Side Wall Vent Terminal
The side wall vent hood (listed in Table 1) must
be used when the heater is vented through a side wall.
It provides a means of installing vent piping through
the building wall, and must be located in accordance
with ANSI Z223.1/NFPA 54 and applicable local
codes. In Canada the installation must be in
accordance with CAN/CGA B149.1 or .2 and local
applicable codes (see Figure 3). Consider the
following when installing the terminal:
1. Through-the-wall vent terminals must terminate
at least 7-feet above a public walkway.
2. Locate the vent terminal so that vent gases
cannot be drawn into air conditioning system
inlets. The National Fuel Gas Code requires that
it be at least 3 feet (0.9m) above any such inlet
that is within a horizontal distance of 10 feet (3m).
3. Locate the vent terminal so that vent gases
cannot enter the building through doors,
windows, gravity inlets or other openings. The
National Fuel Gas Code requires that it be
located at least 4 feet (1.2m) below, 4 feet (1.2m)
horizontally from, or 1 foot (0.3m) above such
openings. Whenever possible, locations under
windows or near doors should be avoided.
4. Locate the vent terminal so that it cannot be
blocked by snow. The National Fuel Gas Code
requires that it be at least 12 inches (30 cm)
above grade, but the installer may determine it
should be higher, depending upon local
conditions.
5. Locate the terminal so the vent exhaust does not
settle on building surfaces and other nearby
objects. Vent products may damage such
surfaces or objects.
6. Locate the terminal at least 6 feet (1.8m)
horizontally from any gas or electric metering,
regulating, or relief equipment.
7. If the PowerMax uses ducted combustion air
from an intake terminal located on the same wall,
locate the vent terminal at least 3 feet (0.9m)
horizontally from the combustion air terminal,
and locate the vent terminal at least 1 foot (0.3m)
above the combustion air terminal.
8. Note that side wall vent terminals for models
750-2000 are shipped with reducers for the vent
collars, to accommodate horizontal vent sizes,
shown in Table 1.
WARNING
The outdoor vent terminal gets hot. Unit must be
installed in such a way as to reduce the risk of
burns from contact with the vent terminal.
Figure 3. Combustion Air and Vent Through Side Wall.
*When vent terminal is less than 10 feet (3m) horizontally
from a forced air inlet, the terminal must be at least 3 feet
(0.9m) above the air inlet.

Pentair Water Commercial Pool and Aquatics
Page 10
2.3.2 Side Wall Combustion Air Terminal
Never obtain combustion air from the pool area.
Corrosion of and/or damage to the pool heater may
result. The side wall combustion air terminal (listed in
Table 1) must be used when the unit takes its
combustion air through a duct from a side wall.
Consider the following when installing the terminal:
1. Do not locate the air inlet terminal near a source
of corrosive chemical fumes (e.g., cleaning fluid,
chlorinated compounds, etc.)
2. Locate the terminal so that it will not be subject
to damage by accident or vandalism.
3. Locate the combustion air terminal so that it
cannot be blocked by snow. The National Fuel
Gas Code requires that it be at least 12 inches
(30 cm) above grade, but the installer may
determine it should be higher, depending upon
local conditions.
4. If the PowerMax is side-wall vented to the same
wall, locate the vent terminal at least 3 feet
(0.9m) horizontally from the combustion air
terminal, and locate the vent terminal at least 1
foot (0.3m) above the combustion air terminal
(see Figure 3).
2.3.3 Vertical Vent Terminal
When the unit is vented through the roof, the
vent must extend at least 3 feet (0.9m) above the point
at which it penetrates the roof. It must extend at least 2
feet (0.6m) higher than any portion of a building
within a horizontal distance of 10 feet (3.0m), and
high enough above the roof line to prevent blockage
from snow. When the combustion air is taken from the
roof, the combustion air must terminate at least 12"
(30cm) below the vent terminal (see Figure 2).
2.3.4 Vertical Combustion Air Terminal
When combustion air is taken from the roof, a
field-supplied rain cap or an elbow arrangement must
be used to prevent entry of rain water (see Figure 2).
The opening on the end of the terminal must be at
least 12" (30cm) above the point at which it penetrates
the roof, and high enough above the roof line to
prevent blockage from snow. When the vent
terminates on the roof, the combustion air must
terminate at least 12" (30cm) below the vent terminal.
2.4 Vent Terminals for Outdoor Units
For outdoor applications, the vent and
combustion air openings must be covered with proper
terminals to prevent rain, snow and other objects from
falling into the PowerMax.
Part numbers for the terminals to cover the vent
and combustion air openings are shown in Table 6.
Vent opening must be on top of the unit, and the
combustion air opening must be on the back of the
unit. The terminals are connected directly to the unit.
No vent piping is used.
Outdoor Vent Outdoor
Model (Size) Terminal Combustion
Air Terminal
500 20254703 D2007900
750 20254705 D2007900
1000 20254705 D2008000
1250 D2007700 D2008000
1500 D2007700 D2008000
1750 D2007800 D2008000
2000 D2007800 D2008200
Table 6. Vent Terminals for Outdoor Units
Alternately, the installer may use a short piece of
galvanized single wall or B-vent and an approved rain
cap for the vent termination. A minimum 12" of vent
height is acceptable. In addition, a properly sized
single wall galvanized 90° ell can be used for the
intake air terminal, with the open end of the ell facing
down to prevent rain infiltration. The combustion air
inlet opening must still be high enough to prevent
blockage by snow (see Section 2.3.2).
SECTION 3.
Gas Supply and Piping
3.1 Gas Supply and Piping
Gas piping should be supported by suitable
hangers or floor stands, not by the appliance.
The heater’s gas train allows the user to pipe the
gas from either the right side or the left side of the
unit. As shipped, the right side of the gas train is
capped off, and there is a manual valve on the left
side. If desired, the manual valve on the left side of the
gas train may be moved to the right side, and the cap
on the right side may be moved to the left.
Review the following instructions before
proceeding with the installation.
1. Verify that the appliance is fitted for the proper
type of gas by checking the rating plate. This
appliance is normally equipped to operate at
elevations up to 2000 feet (610m). PowerMax
appliances may be adjusted to operate properly at
higher elevations; however, input will be reduced
if the heating value of the gas supply is below
sea level values.
2. The maximum inlet gas pressure must not exceed
13" W.C (3.2kPa). The minimum inlet gas
pressure is 5" W.C. (1.2kPa).
3. Refer to Table 7, size supply.

PowerMax Pool Heater Page 11
Distance from Gas Meter or Last Stage Regulator
Model and
Gas Type 0-100' 0-31m 100-200' 31-61m 200-300' 61-91m
500 natural 1-1/2" 3.8cm 2" 5.1cm 2" 5.1cm
500 propane 1" 2.5cm 1-1/2" 3.8cm 1-1/2" 3.8cm
750 natural 2" 5.1cm 2" 5.1cm 2-1/2" 6.4cm
750 propane 1-1/2" 3.8cm 1-1/2" 3.8cm 2" 5.1cm
1000 natural 2" 5.1cm 2-1/2" 6.4cm 3" 7.6cm
1000 propane 1-1/2" 3.8cm 2" 5.1cm 2-1/2" 6.4cm
1250 natural 2-1/2" 6.4cm 2-1/2" 6.4cm 3" 7.6cm
1250 propane 2" 5.1cm 2" 5.1cm 2-1/2" 6.4cm
1500 natural 2-1/2" 6.4cm 3" 7.6cm 3" 7.6cm
1500 propane 2" 5.1cm 2-1/2" 6.4cm 2-1/2" 6.4cm
1750 natural 2-1/2" 6.4cm 3" 7.6cm 3" 7.6cm
1750 propane 2" 5.1cm 2-1/2" 6.4cm 2-1/2" 6.4cm
2000 natural 3" 7.6cm 3" 7.6cm 3-1/2" 8.9cm
2000 propane 2-1/2" 6.4cm 2-1/2" 6.4cm 3" 7.6cm
Notes:
1. These figures are based on 1/2" (0.12kPa) water column
pressure drop.
2. Check supply pressure and local code requirements before
proceeding with work.
3. Pipe fittings must be considered when determining gas pipe
sizing.
Table 7. Gas Piping Size.
4. Run gas supply line in accordance with all
applicable codes.
5. Locate and install manual shutoff valves in
accordance with state and local requirements.
6. A sediment trap must be provided upstream of
the gas controls.
7. All threaded joints should be coated with piping
compound resistant to action of liquefied
petroleum gas.
8. The appliance and its individual shutoff valve
must be disconnected from the gas supply piping
during any pressure testing of that system at test
pressures in excess of 1/2 PSIG (3.45kpa).
9. The unit must be isolated from the gas supply
system by closing its individual manual shutoff
valve during any pressure testing of the gas
supply piping system at test pressures equal to or
less than 1/2 PSIG (3.45kpa).
10. The appliance and its gas connection must be
leak tested before placing it in operation.
11. Purge all air from gas lines.
Caution
Do not use open flame to check for leaks.
NOTE: The PowerMax appliance and all other gas
appliances sharing the gas supply line must be firing
at maximum capacity to properly measure the inlet
supply pressure. The pressure can be measured at
the supply pressure port on the gas valve. Low gas
pressure could be an indication of an undersized gas
meter, undersized gas supply lines and/or an
obstructed gas supply line. The PowerMax may not
fire if the gas pressure lower than 5" w.c.
SECTION 4.
Water Connections
Hot water piping should be supported by suitable
hangers or floor stands. Do not support piping with
this appliance. Due to expansion and contraction of
copper pipe, consideration should be given to the type
of hangers used. Rigid hangers may transmit noise
through the system resulting from the piping sliding in
the hangers. It is recommended that padding be used
when rigid hangers are installed. Maintain 1"
clearance to combustibles for hot water pipes.
Pipe the discharge of the relief valve (full size) to
a drain or in a manner to prevent injury in the event of
pressure relief. Install shutoff valves where required
by code.
PowerMax pool heaters are equipped with
mounted pumps, which serve the heater plus 30 feet of
full-sized piping with a normal number of fittings. If
the pool’s loop is more than 15 feet away from the
heater, please contact the factory.
A mixing system is shipped with the heater, to be
mounted in the field. The system consists of a three-
way valve, temperature control and piping. The
temperature sensor for the control is in the heater inlet.
When the control detects water temperature that is
below 120°F (49°C), it will direct the three-way valve
to actuate, which sends water from the outlet of the
heater back to the inlet. The outlet water that is
diverted to the inlet mixes with the return water from
the pool, and keeps the inlet temperature at or above
120°F (49°C) (see Figure 4). This keeps cold return
water from causing condensing on the outside of the
PowerMax heat exchanger.
See Figure 5 for proper connection of the
PowerMax heater to the pool loop.
Figure 4. Mixing System.
4.2 Automatic Chlorinators
A concentration of chlorine in the heater can be
very destructive; therefore the following rules about
the installation and operation of such devices must be
followed:

Pentair Water Commercial Pool and Aquatics
Page 12
1. The chlorinator should be installed so it
introduces the gas or solution downstream of the
heater.
2. The chlorinator should be wired so it cannot
operate unless the filter pump is operating.
3. The chlorinator should be provided with an anti-
siphon device so that the draining of the piping
after the pump shuts off will not siphon chlorine
solution into the heater.
4. When the operation of a chlorinator is such that
it must be installed in the pump suction, or some
other place where the chlorine solution flows
through the heater, corrosion of the heater can
occur. Excessive concentrations of chlorine
resulting from improper adjustment or
chlorinator equipment failure are responsible for
this corrosion. The heater warranty does not
cover the resulting damage to the heat exchanger.
4.3 Sensor Locations
Two sensors must be installed in the pool loop,
as shown in Figure 5. The inlet sensor for the
temperature control must be installed in the pool loop
within 12” (30 cm) of the inlet to the heater. This
sensor is not installed in a well. For sensitivity, it must
be installed in direct contact with the pool water flow.
The second sensor, the high limit sensor, must be
installed in the pool loop within 12” (30 cm)
downstream of the heater outlet. This sensor is a
capillary and bulb. It shall be used with the immersion
well that is provided.
Figure 5. Pool Heater Piping.
The PowerMax Pool Heater is shipped with a field-installed mixing system, and must be piped in
primary-secondary style, as shown. A remote pool temperature sensor and remote pool temperature
high limit are wired to the PowerMax, to be mounted in the pool water loop, as shown.
SECTION 5.
Electrical Connections
WARNING
The appliance must be electrically grounded in
accordance with the requirements of the authority
having jurisdiction or, in the absence of such
requirements, with the latest edition of the National
Electrical Code, ANSI/NFPA 70, in the U.S. and
with latest edition of CSA C22.1 Canadian Electrical
Code, Part 1, in Canada. Do not rely on the gas or
water piping to ground the metal parts of the boiler.
Plastic pipe or dielectric unions may isolate the
boiler electrically. Service and maintenance
personnel, who work on or around the boiler, may
be standing on wet floors and could be electrocuted
by an ungrounded boiler.
Single pole switches, including those of safety
controls and protective devices must not be wired in a
grounded line.
All electrical connections are made in the field
wiring terminal strip, which is located at the right side
of the appliance.
NOTE: All internal electrical components have been
prewired. No attempt should be made to connect
electrical wires to any other location except the field
wiring strip.

PowerMax Pool Heater Page 13
Figure 6). The LCD screen will display the pool loop
return temperature during normal operation. When the
control is first powered up, it displays . It then
displays the temperature at the pool loop sensor. After
the temperature is displayed, the current settings
(parameters) may be viewed. To scroll through the
parameters, press the down arrow button to advance to
the next parameter.
5.3.2 Programming Control Parameters
There are thirteen (13) control parameters. Only
three (3) of those should be set, LSP, dLS and Pd. The
remaining parameters are factory set and should not be
changed.
The pool loop temperature (desired pool
temperature) is set by changing the LSP parameter.
After scrolling through the parameters until LSP is
displayed, press the enter button. The setpoint will be
displayed. Press the up arrow or down arrow buttons
until the desired setpoint is displayed. Press the enter
button and the setpoint will be activated. The display
will return to indicating the present pool loop
temperature.
In addition to the ability to set the pool loop
temperature, the differential associated with that
setting may also be adjusted. The differential is set by
changing the dLS parameter. After scrolling through
the parameters until dLS is displayed, press the enter
button. The setpoint will be displayed. Press the up
arrow or down arrow buttons until the desired setpoint
is displayed. Press the enter button and the setpoint
will be activated. The display will return to indicating
the present pool loop temperature.
The last parameter that may be adjusted is Pd,
the pump off delay. After again scrolling through the
parameters until Pd is displayed, press the enter
button. The pump delay time will be displayed. The
pump off delay may be set between 0.1 and 10
minutes. Press the up arrow or down arrow buttons
until the desired setpoint is displayed. Press the enter
button and the setpoint will be activated. The display
will again return to indicating the present pool loop
temperature.
Figure 6. Pool Heater Controller.
5.1 Main Power
PowerMax appliances are fitted with pigtail
leads for main power connection. Connect a fused 15-
ampere, 120-volt supply to the black wire. Neutral leg
is connected directly to the white wire. Ground wire is
connected to the green wire.
Wiring diagrams are shown in Section 10 in
Figures 12 through 15. Field wiring is shown in
Section 10 in Figures 16 and 17.
IMPORTANT NOTE: If the backwash operation is
manual the heater must be shut off manually during
backwashing.
Auxiliary Time Clock Wiring:
If a time clock is used to control the pool filter
pump operation, a separate switch or relay must be
used to shut off heater at least 15 minutes before the
filter pump is shut off. Wire the switch or relay to the
field-wiring board’s “Other Ints” terminals. Wire the
switch or relay to the field-wiring board’s “Other Ints”
terminals, after removing the factory-installed jumper.
All field-installed electrical safety devices and
field-installed controllers can be connected in series to
the heater’s “Other Ints” terminals on the field-wiring
board (remove the factory-installed jumper).
5.2 Temperature (Operating) Control
The PowerMax temperature control operates by
measuring the pool loop return temperature, before the
heater inlet piping. It is adjustable to a maximum of
104° F and will prevent heater operation at return
temperatures above 104° F. It also controls the pool
heater pump and the temperature of the water entering
the heat exchanger. It also controls the PowerMax
pump operation and the mixing system, which tempers
the water entering the heat exchanger to prevent
damage from condensation. The sensors for the
control are installed as shown in Figure 5 and Section
4.3, Sensor Locations. The automatic mixing system
sensor, already installed, is shown in Figure 4. During
operation, the automatic mixing system diverts water
from the outlet to the inlet to “pre warm” the water to
a minimum inlet temperature of 120°F. This prevents
condensation from forming, which can damage the
heater.
5.3 Programming the Temperature
Control
5.3.1 Temperature Control Overview
The digital display on the control has the
following uses:
• To display the actual pool loop temperature
during normal operating mode.
• To allow the user to view and adjust the
control settings.
Figure 6 identifies the control buttons.
The Pool Heater Temperature Control face
contains an LCD screen and four (4) buttons (see

Pentair Water Commercial Pool and Aquatics
Page 14
By depressing the upper left hand button at any
time during the programming, the menu may be
returned to the beginning.
5.3.3 Setpoint - LSP
The setpoint is the desired temperature around
which the heater will control (desired pool
temperature). It is adjustable between 60° F and
104° F.
5.3.4 Differential - dLS
The differential (dLS) is the number of degrees
between the temperature at which the heater turns off
and the temperature at which the heater restarts. It is
adjustable from 2° F to 10° F.
5.3.5 Pump Operation
The pump is energized whenever there is a heat
demand.
5.3.6 Heater Purge (Pump Delay) - Pd
After a demand is satisfied, the pump will
continue to run for a preset length of time. That length
of time is adjustable from 0.1 to 10 minutes and is
programmed by the parameter Pd.
Caution
Should overheating occur or the gas supply fail to
shut off, turn off the manual gas control valve to the
appliance.
5.4 Limit Controls
In addition to the pool heater temperature
control, PowerMax appliances are fitted with a Pool
Loop high limit set at 135° F and an automatic reset
heater high limit with a maximum setting of 190° F.
The Pool Loop high-limit sensing bulb is to be
installed in the sensor well (supplied), downstream of
the heater (see Figure 5). If sufficient capillary length
exists to reach the sensor location, the control may
remain in its location near the rear of the cabinet on
the right side, behind the slide out drawer (see Figure
8). If the sensor location is farther from the heater than
the capillary will reach to, then the control should be
moved to the remote location and the wires extended
to the new location of the control. If the controller
needs to be moved, and it is being moved to an
outdoor location, the control will need to be put in a
weather-tight enclosure to protect it from rain, snow,
etc.
The other limit control limits the temperature of
the discharge from the heat exchanger to a maximum
of 190° F. This limit should be set to a minimum of
175° F. To set the limit controls, remove the control
panel cover and pull the control panel out to gain
access. Appliances with reversed heat exchangers have
the limit controls relocated to the left side of the
appliance. The left access door must be removed to
gain access to the limit controls on these appliances.
SECTION 6.
Operating Instructions
6.1 Sequence of Operation
The amber “Ready” light on the front panel
indicates that the control system is energized. Upon a
call for heat from the pool temperature control, the
green “Heat” indicator on the front panel will light.
The green “Pump” indicator on the front panel
will light.
Once the water flow switch makes, and if all of
the safety interlocks are closed, the ignition module(s)
will energize the blower(s) for a 15-second pre-purge,
followed by a 20-second period to allow the ignitor(s)
to heat.
Energizing the blower pressurizes the air box
(which supplies air to the burners) and closes the
normally-open contact(s) of the airflow pressure
switch(es). This allows the ignition module to proceed
with the ignition sequence.
The blocked flue pressure switch senses the
pressure difference between the exhaust plenum and
the blower inlet plenum. It will interrupt the airflow
sensing circuit if this pressure exceeds a maximum
value. If airflow is not proven, the ignition module
will either attempt ignition again (up to three times) or
will lockout (if the optional lockout ignition module is
used).
The ignition module checks that the ignitor
current has reached a minimum value and energizes
the gas valves at the end of the ignitor-heating period.
The green indicators on the front panel will light,
indicating that the gas valves are open.
After a 4-second trial for ignition, the ignitor
switches off, and unless the flame sensor detects a
flame, the gas valves will close and the ignition
module will either attempt ignition again (up to three
times) or will lockout (if the optional lockout ignition
module is used). Note: at this point, if gas pressure is
below the required 5" w.c. minimum, the pool heater
will lock out.
If flame is sensed, the burner will continue to fire
as long as there is a call for heat. PowerMax 1250,
1500, 1750 and 2000 models start at part load. When
the gas valves controlled by the first ignition module
are energized, the second ignition module is energized
and enters the same ignition sequence just described.
If there is a subsequent loss of flame signal, the burner
will attempt re-ignition up to three times (only once if
optional lockout ignition module is used.) Loss of
flame signal from the first ignition module will cause
shutdown of the heater.
When the call for heat is satisfied, the gas valves
close and the blower(s) continues to run for 30
seconds. The pump will continue to run for the length
of time selected at startup by the adjustment of the
pump time delay (Pd).

PowerMax Pool Heater Page 15
If a call for heat is prevented from being satisfied
either by a safety interlock or due to an ignition
lockout, the red “Service” indicator on the front panel
will light. To reset the standard ignition module,
toggle the PowerMax power switch off, and then on
again. (To reset the optional single try lockout ignition
module, the reset button on the module must be
pressed. Interrupting power to this module will not
reset the lockout.)
The PowerMax 1250, 1500, 1750 and 2000
models have two ignition modules that control
different burners.
6.2 Filling the Heater System
1. Ensure the system is fully connected, filled with
water and all valves are open.
2. Start up heater according to the procedure in this
manual. Operate the entire system for one (1)
hour.
3. After placing the unit in operation, the ignition
system safety shutoff device must be tested.
First, shut off the manual gas valve, and call the
unit for heat. After the pre-purge and ignitor
heat-up time, the main gas terminals will be
energized, attempting to light, for four (4)
seconds, and then will de-energize. The unit will
go into lockout mode. Second, turn the power off
and then on again, push the reset button (optional
Ignition Module only), open the manual gas
valve and allow the unit to light. While the unit
is operating, close the manual gas valve and
ensure that power to the main gas valve no
longer exists.
4. Check the entire system for leaks.
Caution
Protect the heater from low pH water if an “acid
start up” or similar technique is used. Corrosion of
the heater and heat exchanger due to low pH water
is not covered under the limited warranty. The water
must be neutralized to normal pH levels before
filling the heater and starting up the system.
Important: The installer is responsible for identifying
to the owner/operator the location of all emergency
shutoff devices.
WARNING
Do not use this appliance if any part has been
under water. Immediately call a qualified service
technician to inspect the appliance and to replace
any part of the control system and any gas control
that may have been under water.
6.3 Operating the Burner and Set Up
6.3.1 Set Up for 0 to 2500 Feet Altitude
The setup must be checked before the unit is put
in operation. Problems such as failure to start, rough
ignition, strong exhaust odors, etc. can be due to
improper setup. Damage to the heater resulting from
improper setup is not covered by the limited warranty.
1. Using this manual, make sure the installation is
complete and fully in compliance with the
instructions.
2. Determine that the appliance and system are
filled with water and all air has been bled from
both. Open all valves.
3. Observe all warnings on the Operating
Instructions label and turn on gas and electrical
power to appliance.
4. Switch on the appliance power switch located on
the right side of the unit.
5. The PowerMax will enter the start sequence, as
long as the unit is being called for heat. The
blower and pump come on for pre-purge, then
the ignitor warm-up sequence starts and after the
ignitor warm-up is complete and all safety
devices are verified, the gas valves open. If
ignition doesn’t occur, check that there is proper
gas supply. Wait 5 minutes and start the unit
again. During initial start up, air in the gas line
may cause the PowerMax to "lock out" during
the first few trials for ignition. Depending on the
ignition modules installed, the manual reset
button on the ignition module(s) may need to be
depressed to restart the heater.
6. When the unit is running, the supply gas pressure
must be checked. Inlet gas pressure must not
exceed 13" W.C. (3.2kPa). The minimum inlet
gas pressure is 5" W.C. (1.2kPa).
7. Once the inlet gas pressure is verified, the outlet
gas pressure from each valve (manifold gas
pressure) must be checked, and adjusted, if
necessary. The manifold gas pressure must be
2.5" W.C. (0.62kPa).
8. Complete the setup by checking the CO2at the
outlet of the unit. The CO2should be 8% for
natural gas, or 9.2% for propane.
9. After placing the appliance in operation, the
Burner Safety Shutoff Device must be tested.
To test:
(a) Close gas shutoff valve with burner
operating.
(b) The flame will go out and blower will
continue to run for the post purge cycle.
Three (3) additional attempts to light will
follow (only one (1) attempt for optional
module). Ignition will not occur as the gas
is off. The ignition control will lockout, and
will have to be reset before the unit will
operate. The ignition control reset button is
located on each ignition control, in the

Pentair Water Commercial Pool and Aquatics
Page 16
After all of the gas valve manifold pressures
have been set, the CO2or O2must be reset. CO2or O2
will have changed when the manifold pressure was
adjusted. Open the air shutter(s) to reduce the CO2or
O2to the values achieved previously.
The procedure is complete when all gas valves
are adjusted to a manifold pressure of 3.0 in. W.C.
(0.75 kPa) and the CO2is adjusted to 8.0% for Natural
Gas appliances or 9.2% for LP appliances. When
using an O2analyzer, the correct O2is 6.8% for both
Natural Gas and LP appliances.
Caution
Should any odor of gas be detected, or if the gas
burner does not appear to be functioning in a
normal manner, close main shutoff valve, do not
shut off switch, and contact your heating contractor,
gas company, or factory representative.
6.4 Shutting Down the PowerMax
1. Switch off the main electrical disconnect switch.
2. Close all manual gas valves.
3. If freezing is anticipated, drain the PowerMax
and be sure to also protect building piping from
freezing.
This step to be performed by a qualified
service person.
6.5 Spring and Fall Operation
Stand-by Service
Turn the thermostat down to approximately 70°F
(21°C). This will prevent the pool and surrounding
ground from becoming chilled and permit the pool to
be raised to swimming temperature in a shorter length
of time. Do Not Operate below 60°F (16°C).
6.6 Winter Operation
Complete Shutdown
1. See Section 6.4
2. If the heater is not protected from freezing
temperatures, it should be completely drained
before the first frost. Drain the heater by
removing the plug at the end of the inlet/outlet
header casting. Also, remove the small plug at
the bottom of the pump housing. Do not replace
either plug until the time that refilling is desired.
The heater must be level for complete draining.
When compressed air is used to blow out lines, it
is still necessary to follow these directions.
Because of the potential for electrical power
failure or pump failure, freeze protection should
never be accomplished by operating the pool
heater and the filter pump. Either of those
failures will potentially allow a freeze up and
cause damage to the heater and the attached
system.
lower right corner, and can be reset by
depressing. It is not marked on the ignition
control label.
(c) Open gas shutoff valve. Restart the
appliance. The ignition sequence will start
again and the burner will start. The
appliance will return to its previous mode
of operation.
NOTE: Models 1250, 1500, 1750 and 2000 have two
ignition controls and two ignitors.
6.3.2 High Altitude Adjustment and Set Up
PowerMax appliances may be operated at high
altitude (7700 ft., 2347 m) with a reduction in output of
approximately 10%. At elevations higher than 7700 ft.
(2347 m) the reduction in output will exceed 10% and at
elevations below 7700 ft. (2347 m) it will be less than
10%. When adjusted properly, the appliance will perform
properly at any altitude. High altitude adjustment must
not be made on appliances operating at elevations below
2500 ft. (762 m).
No orifice changes are required to adjust the
PowerMax appliances for high altitude. High altitude
adjustment is accomplished by adjustment of the gas
valve manifold pressure and the air shutter(s). The
required instruments used to assist in these
adjustments are a CO2or O2Analyzer and a U-Tube
Manometer or other device capable of reading a
pressure of 2.5-3.0 inches W.C. (0.62-0.75 kPa).
Start the adjustment process by checking the
CO2 in the “as installed” condition. Adjust the air
shutter(s) so that the CO2is about 8% or the O2is
about 6.8% for appliances operating on Natural Gas.
For appliances operating on LP Gas adjust the air
shutter(s) so that the CO2is about 9.2% or the O2is
about 6.8%. Appliances with two blowers should be
adjusted so that the air shutters below each blower are
open the same amount.
Once the CO2or O2has been set, the manifold
pressure may be adjusted. Remove the 1/8 NPT plug
from the lower side of the gas valve that is to be set
and install a fitting, hose and manometer. Start the
appliance and observe the manifold pressure.
Manifold pressure must be adjusted to 3.0 in. W.C.
(0.75 kPa) (for high altitude only, standard operating
pressure is 2.5 in. W.C. (0.62 kPa)). It is adjusted by
removing the slotted cap on the gas valve and turning
the adjustment screw (beneath the cap) clockwise to
increase pressure . After the adjustments have been
completed, the fitting, hose and manometer have been
removed and the 1/8" plug has been replaced, replace
the cap. Repeat this process until all gas valves have
been set. Note: The pressure can be set only when the
appliance is operating and only when the particular
gas valve being adjusted is energized by a call for
heat.

PowerMax Pool Heater Page 17
3. Improper use of the heater: This PM pool
heater is not designed for continuous use as a
“anti-freezing” device for pools. Operating the
heater at low water temperatures will damage the
heat exchanger.
6.7 To Restart the PowerMax
If drained, follow Section 6.2 in this manual for
proper filling and purging.
1. Switch off the main electrical disconnect switch.
2. Close all manual gas valves.
3. WAIT FIVE (5) MINUTES.
4. Set the pool aquastat to its lowest setting.
5. Open all manual gas valves.
6. Reset all safety switches.
7. Set the temperature controller to the desired
temperature setting and switch on electrical
power.
8. Burner will go through a prepurge period and
ignitor warm-up period, followed by ignition.
6.8 Therapeutic Pools (Spas)
Therapeutic pools or “spa” pools are usually
piped and controlled so that very warm or hot water,
often with air injection, is forced at high velocity into
a confined area of a swimming pool or into a small
separate pool. For the purposes of this manual, any
application in which the water temperature is
maintained above 85°F (30°C) is considered a spa.
SPECIAL SET-UP AND OPERATING
PROCEDURES APPLY TO SPAS.
1. Models PM1000 and larger should not be used
for spas due to their higher temperature rises.
2. To ensure that the spa inlet does not exceed 104°F
(40°C), the spa filter pump must circulate water
at the minimum flow rates shown in Table 8.
Heater Model Minimum Filter
Pump Flow Rate
PM 500 240 GPM
PM 750 360 GPM
Table 8. Minimum Filter Pump Flow Rates For Spas.
NOTE: Maximum Spa Temperature Is Assumed To Be
100°F (38°C).
3. Spas are excellent for relaxation, body-
conditioning and for arthritic and rheumatic
problems, but can be hazardous.
WARNING
The U. S. Consumer Product Safety Commission
has warned that elevated temperatures in spas and
hot tubs can be hazardous. Follow these “Safety
Rules for Hot Tubs:”
• Spa or hot tub water temperatures should never
exceed 104°F (40°C). A temperature of 100°F
(38°C) is considered safe for a healthy adult.
Special caution is suggested for young children.
• Drinking of alcoholic beverages before or
during hot tub use can cause drowsiness,
which could lead to unconsciousness and
subsequently lead to drowning.
• Pregnant women beware! Soaking in water
above 102°F (39°C) can cause fetal damage
during the first three months of pregnancy
(resulting in the birth of a brain-damaged or
deformed child). Pregnant women should stick
to the 100°F (38°C) maximum rule.
• Before entering the spa or hot tub, users should
check the water temperature with an accurate
thermometer; spa or hot tub thermostats may
err in regulating water temperatures by as
much as 4°F (2°C).
• Persons with a medical history of heart disease,
circulatory problems, diabetes or blood
pressure problems should obtain their
physician’s advice before using spas or hot
tubs.
• Persons taking medications which induce
drowsiness, such as tranquilizers,
antihistamines or anticoagulants, should not
use spas or hot tubs.
SECTION 7.
Maintenance
7.1 System Maintenance
1. Lubricate the system water-circulating pump, if
required, per the instructions on the pump.
2. Inspect the venting system for obstruction or
leakage at least once a year. Periodically clean
the inlet air filter and the screens in the vent
terminal and combustion air terminal (when
used).
3. Keep the appliance area clear and free from
combustible materials, gasoline, and other
flammable vapors and liquids.
4. If the appliance is not going to be used for
extended periods in locations where freezing
normally occurs, it should be isolated from the
system and completely drained of all water. All
systems connected to it should also be drained or
protected from freezing.
5. Low water cutoffs, if installed, should be
checked every 6 months. Float type low water

Pentair Water Commercial Pool and Aquatics
Page 18
an 83% arrestance. Since the filter is washable, it will
only need replacement in very rare cases. If filter
replacement is needed, it should only be replaced with
a factory part. Inspect the air filter. If there is debris on
the air filter, remove it from the filter box, and wash it
with mild soap and water. Ensure that the filter is
completely dry before re-installing, in reverse order.
7.2.3 Gas Valves
The gas valves are designed to operate with
supply pressures of 4-13 inches w.c. (1.0 to 3.2 kPa).
To remove a valve, shut off 120-volt power and
the manual gas shutoff valve. Remove the top front
panel from the unit. Disconnect the wires to the valve.
Disengage the unions before and after the valve, and
remove the valve. Pull the pipe nipples from the inlet
and outlet of the valve, and clean the threads on the
pipe nipples for re-use. Apply pipe dope to the pipe
nipples (threaded joints should be coated with piping
compound resistant to action of liquefied petroleum
gas), and re-install in reverse order. Turn on manual
gas shutoff valve and 120 volt power and check
appliance operation and tightness of gas valve
connections.
7.2.4 Pool Loop High Limit Control
The high limit switch is an automatic reset
switch with an adjustable set point, up to 135°F
(57°C). To replace the switch, shut off the 120-volt
power to the appliance. Remove the cover from the
switch to access the mounting screws. Remove the
screws, and pull the switch off the control panel.
Remove the capillary and bulb from the thermal well
located in the pool loop adjacent to the heater outlet.
Replace in reverse order.
7.2.5 Automatic Reset High Limit Control
An automatic reset high limit is used to limit
heater water from exceeding 200°F. The high limit
switch has an adjustable set point, up to 190°F (88°C).
To replace the switch, shut off the 120-volt power to
the appliance. Remove the cover from the switch to
access the mounting screws. Remove the screws, and
pull the switch off the control panel. Remove the
capillary and bulb from the thermal well located in the
header. Replace in reverse order.
7.2.6 Temperature Control
The temperature control is a single stage control.
To replace the control, shut off the 120-volt power to
the appliance. Unplug all of the electrical connectors,
remove the retainer clip and the control. Replace in
reverse order.
7.2.7 Ignition Controls
The ignition controls ensure the proved
interrupted-type ignition system. They control the hot
surface ignitor(s) and prove that the flame signal is
cutoff should be flushed periodically.
6. Inspect flue passages, and clean with brushes/
vacuums, if necessary. Sooting in flue passages
indicates improper combustion. Determine the
cause and correct.
7. Inspect the vent system and air intake system,
and ensure that all joints are sealed properly. If
joints need to be resealed, completely remove
existing sealing material, and clean with alcohol.
Apply new sealing material, and re-assemble.
7.2 Appliance Maintenance and
Component Description
Only genuine Pentair Water Commercial Pool and Spa
replacement parts should be used.
Caution
Label all wires prior to disconnection when servicing
controls. Wiring errors can cause improper and
dangerous operation. Verify proper operation after
servicing.
See Figures 7 through 11 for location of gas train
and control components.
The gas and electric controls on the appliance are
engineered for long life and dependable operation, but
the safety of the equipment depends on their proper
functioning. It is strongly recommended that a
qualified service technician inspect the basic items
listed below every year.
a. Ignition controls
b. Ignitors
c. Water temperature control
d. Automatic gas valve
e. Pressure switches
f. Blowers
7.2.1 Burners
Close main manual gas valve before proceeding.
Checking the burners for debris - Remove the ignitor
inspection panels(s) and ignitor(s) and inspect the
burners through the ignitor hole(s) using a flashlight to
illuminate. If there is any indication of debris on the
burners that are visible, all the burners will need to be
inspected more thoroughly. Remove the screws from
around the front of the air box (large panel from which
the ignitor inspection panel(s) were removed), and
remove the large panel. Remove the gas manifold
assemblies and the burner panels. Inspect the burners.
Clean burners, if necessary, by blowing compressed
air from the outside of the burners into the center of
the burner. A dirty burner may be an indication of
improper combustion or dirty combustion air.
Determine the cause, and correct. Replace the burners
in the reverse order.
7.2.2 Filter
The filter used in the PowerMax is washable with

PowerMax Pool Heater Page 19
operates properly, by following the set-up procedure
in this manual. Use caution in handling the blower,
ensuring you do not put pressure on the blower wheel.
7.2.12 Flow Switch
The PowerMax uses a paddle-type flow switch to
ensure that the unit has water flow before ignition is
allowed.
7.2.13 Heat Exchanger Coil
Caution
Black carbon soot buildup on a dirty heat exchanger
can be ignited by a random spark or flame. To
prevent this from happening, dampen the soot
deposits with a wet brush or fine water spray before
servicing the heat exchanger.
The PowerMax has a pre-mixed burner system.
These systems provide the burners with sufficient air
for complete combustion, and black carbon sooting is
seldom experienced. If sooting is suspected, view
ports for inspection of the heat exchanger are provided
on both sides of the heater. They are located below the
headers, and are accessed by opening the small round
cover that is attached by one screw. In the unlikely
event that there is a buildup of black carbon soot or
other debris on the heat exchanger, clean per the
following:
1. Disconnect the electrical supply to the unit.
2. Turn off the gas supply by closing the manual
gas valve on the heater.
3. Disconnect and remove the wires, conduit and
sensors from all components that are attached to
the inlet/outlet header.
4. Isolate the heat exchanger from the water supply.
5. Disconnect the header flanges from the inlet and
outlet.
6. Allow the heat exchanger to drain. Remove the
front cover(s). Remove the venting and remove
the top, by removing the screws that attach the
top to the side panels. Remove the side panels.
Remove the front lower panels sealing the
combustion area. To remove the gas train,
disconnect the unions located above the
intermediate pan and the field installed union
located outside the cabinet, and pull up, bringing
the union end connectors through the grommets
in the intermediate pan. To remove the
intermediate pan, remove the slide out control
assembly and blower(s) to reveal the screws.
Remove the screws holding the intermediate pan,
and lift up to remove it. The heat exchanger has
integral metal sections attached, which connect
to the frame of the boiler. Locate and remove
the screws along the front, rear and bottom of the
appropriate for powering the gas valves. It also
controls the blower’s pre-purge and post-purge.
PowerMax models 500, 750 and 1000 have one
ignition control. Models 1250, 1500, 1750 and 2000
have two ignition controls. On these models, one
ignition control provides for part-load start-up and the
second control brings the heater to full rate, after the
first control has started the part-load burners.
To replace a control, shut off the 120-volt power
to the appliance. Remove the cover from the control
panel. Remove the electrical connectors from the
ignition control. Take out the controller’s mounting
screws, and pull the controller out. Replace in reverse
order.
7.2.8 Ignitors
The ignitors used are 120v “Hot Surface” type.
They are energized whenever there is a call for heat
and switched off when ignition is established and the
flame has been sensed. PowerMax models 500, 750
and 1000 have one ignitor. Models 1250, 1500, 1750
and 2000 have two ignitors. To replace the ignitor,
shut off the 120- volt power to the appliance, remove
the ignitor access panel, disconnect the Molex
connector, remove the two mounting screws on the
ignitor flange, and pull the ignitor out. Install in
reverse order, always using a new ignitor gasket with
the replacement ignitor.
Caution
Ignitor gets hot.
7.2.9 Ignition Sensors
The ignition sensors ensure that the main flame
is ignited, so that raw gas is not allowed to fill the
combustion chamber. The ignitors are the ignition
sensors on PowerMax appliances. There are no
separate ignition sensors.
7.2.10 Transformer
The heater's transformer is not capable of
supplying control voltage for external devices. Should
a transformer need replacing, shut off the 120-volt
power. Unplug the transformer wires, remove the
mounting screws and remove the transformer. Replace
transformer in the reverse order.
7.2.11 Blowers
The combustion air blowers bring the
combustion air for the Pennant from the upper
chamber to the lower chamber. Mixing of the gas and
air occurs in the burners. If a blower change is
required, turn off the 120-volt power and gas supply to
the unit. Remove the front panel. Disconnect the
blower’s wire harness. Remove the screws at the
blower flange, and pull the blower out. Replace
blower in reverse order, ensuring that all joints are
made correctly. After replacement, ensure that the unit

Pentair Water Commercial Pool and Aquatics
Page 20
operate best with 45% excess air (8% CO2on
natural gas, 9.2% CO2on LP). Check the CO2of
the appliance and adjust if necessary.
3. Ignitor failure: If the boiler goes through a
normal start cycle but combustion does not
occur, and the gas pressure is at least 5" w.c.,
ignitor failure may be the cause. Check the
ignitor by unplugging it, allowing it to cool to
room temperature, and measuring the ignitor
resistance. It should be 50-80 ohms. If the
resistance is not 50-80 ohms, replace the ignitor.
If the resistance is correct, reset the boiler and
check for 120 VAC at the ignitor plug during the
start cycle. If there is no voltage, replace the
faulty ignitor wire harness or the ignition control.
8.2 Delayed Ignition - Possible Causes
A defective burner can cause a delayed ignition.
If the gas supply pressure is proper and the gas valves
are functioning properly, then burners should be
inspected. There should be no distortion or
perforations in the burners outside of the active burner
port area. Replace if indicated.
8.3 Short Cycling
Because of the large mass of pool systems, short
cycling should not exist. If it does, it will be caused by
insufficient flow in the pool loop. Check that there is
no blockage in the pool loop such as a plugged or
partially plugged pool filter.
8.4 High Gas Consumption
Appliances operating with an improper air/fuel
ratio are very inefficient and consequently, have very
high gas consumption. Because efficiency is high
when the CO2is high (or O2is low), appliances
operating with low CO2or high O2(especially LP
appliances) consume more gas. Adjust the CO2or O2
for optimum efficiency. If no combustion analyzing
equipment (CO2or O2) is available then a proper
adjustment of the air/fuel ratio (CO2or O2) cannot be
accomplished. However, by briefly sniffing the flue
gases it is possible to determine if the CO2or O2is
within the proper range. No significant flue gas odor
should be detected when combustion is proper. A
strong piercing smell indicates poor combustion and
generally a lean mixture - low CO2or high O2 . The
CO2should be 8% (natural gas, 9.2% LP) at high fire.
To check the CO2, first verify that the supply gas
pressure is within 5" to 13" w.c. (1.2 to 3.2 kPa) With
the PowerMax running with both stages firing, set the
air box pressure to 1.5" w.c. (0.37 kPa) (as a starting
point), by adjusting the air shutter(s) at the bottom of
the fan(s). Check the CO2, and adjust the air shutters
if further adjustment to the CO2 is needed. Models
1250, 1500, 1750 and 2000 have two blowers and two
air chambers (boxes). The pressure of each air box
must be equal when the final adjustment is made.
integral metal sections, and remove the heat
exchanger and metal sections by lifting up. On
the larger appliances, a center heat exchanger
support must be unbolted before it can be
removed.
7. Remove the heat exchanger from the unit.
NOTE: The heat exchangers are heavy and will
require two people to remove to avoid personal
injury.
8. Clean the heat exchanger: A light accumulation
of soot or corrosion on the outside of the heat
exchanger can be easily removed. Use a wire
brush to remove loose soot and scale from the
heat exchanger. Do not use water or compressed
air for cleaning.
9. NOTE: While the heat exchanger is out of the
unit, inspect the firewall refractory insulation.
Replace if necessary.
10. Inspect the inside of the copper tubes for scale
buildup. Scale can build up on the inner surface
of the heat exchanger tubes, which can restrict
water flow. If the tubes show signs of scaling,
clean the internal surface. A tube cleaning kit
part number R0010000 is available.
11. Reassemble in the reverse order, and check
appliance operation after start-up.
NOTE: The Warranty does not cover damage
caused by lack of required maintenance, lack of
water flow, or improper operating practices.
SECTION 8.
Trouble Shooting
8.1 Resolving Lockouts
There are many causes of lockouts. The three
most common causes are: (1) inadequate gas supply,
(2) poor combustion, (3) ignitor failure.
1. Inadequate gas supply: Before proceeding,
ensure that the gas supply has not been shutoff or
the LP tank (LP boilers) is not empty. Then,
restart the boiler and observe the operational
cycle. After a 15-second fan pre-purge, the
ignitor will heat up for 20 seconds, and then the
unit will light. If it does not, check the gas
supply pressure to the appliance, after resetting
the appliance and attempting another start-up.
The gas pressure to the appliance must be above
5" W.C. (1.2kPa) throughout the entire start-up
cycle. If it is not, correct the supply problem
(check gas valves or supply piping). If the supply
pressure is adequate, consult the factory for
assistance.
2. Poor Combustion: Poor combustion should be
suspected if there is a strong flue gas odor. The
odor may result from an improper gas/air ratio
(high or low O2or CO2). PowerMax appliances