HTP Pioneer PHR100 Installation manual

Pioneer
Heating Appliance
Installation
Start-Up
Maintenance
Parts
Warranty
PHR100 / 130 / 160 / 199 Models*
* “LP” Denotes Propane Gas Operation
This manual must only be used by a qualied installer / service technician. Read all instructions in this manual before
installing. Perform steps in the given order. Failure to do so could result in substantial property damage, severe
personal injury, or death.
HTP reserves the right to make product changes or updates without notice and will not be held liable for typographical
errors in literature.
NOTE TO CONSUMER: PLEASE KEEP ALL INSTRUCTIONS FOR FUTURE REFERENCE.
272 Duchaine Blvd. New Bedford, MA 02745 www.htproducts.com
LP-325 Rev. 4.4.17
Improper installation, adjustment, alteration, service, or maintenance could void product warranty and cause
property damage, severe personal injury, or death.
California Proposition 65 Warning: This product contains chemicals known to the State of California to cause cancer,
birth defects, or other reproductive harm.
The surfaces of these products contacted by potable (consumable) water contain less than 0.25% lead by weight as
required by the Safe Drinking Water Act, Section 1417.
This Manual For Use With Appliances Manufactured After
April 10, 2017

LP-325 Rev. 4.4.17
2
WARNING: If the information in these instructions is not followed exactly, a re or explosion may result causing property
damage, personal injury or death.
• Do not store or use gasoline or other ammable vapors and liquids in the vicinity of this or any other appliance.
WHAT TO DO IFYOU 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 neighbor’s phone. Follow the gas supplier’s instructions.
• If you cannot reach your gas supplier, call the re department.
• Installation and service must be provided by a qualied installer, service agency or the gas supplier.
Improper installation, adjustment, alteration, service, or maintenance can cause injury, property damage, or death.
Refer to this manual. Installation and service must be performed by a qualied installer, service agency, or gas supplier.

LP-325 Rev. 4.4.17
3
The following dened terms are used throughout this manual
to bring attention to the presence of hazards of various risk
levels or to important product information.
DANGER indicates an imminently hazardous situation
which, if not avoided, will result in serious personal injury or
death.
WARNING indicates a potentially hazardous situation
which, if not avoided, could result in personal injury or death.
CAUTION indicates a potentially hazardous situation which,
if not avoided, may result in moderate or minor personal
injury.
CAUTION used without the safety alert symbol indicates
a potentially hazardous situation which, if not avoided, may
result in property damage.
NOTICE is used to address practices not related to personal
injury.
Foreword
This manual is intended to be used in conjunction with other
literature provided with the appliance. This includes all related
control information. It is important that this manual, all other
documents included in this system, and additional publications
including the Code for the Installation of Heat Producing
Appliances and National Fuel Gas Code - ANSI Z223.1 (latest
versions), be reviewed
in their entirety before
beginning any work.
Installation should be
made in accordance
with the regulations
of the Authority
Having Jurisdiction,
local code authorities,
and utility companies
which pertain to this
type of water heating
equipment.
Authority Having
Jurisdiction (AHJ) – The
AHJ may be a federal,
state, local government,
or individual such as a
re chief, re marshal,
chief of a re prevention
bureau, labor
department or health
department, building
ocial or electrical
inspector, or others
For the Installer
This appliance must be installed by qualied and licensed
personnel. The installer should be guided by the instructions
furnished with the appliance, and by local codes and utility
company requirements. In the absence of local codes, preference
should be given to the National Fuel Gas Code - ANSI Z223.1,
latest version.
Installations Must Comply With:
Local, state, provincial, and national codes, laws, regulations,
and ordinances.
The latest version of the National Fuel Gas Code, ANSI Z223.1,
from American Gas Association Laboratories, 8501 East Pleasant
Valley Road, Cleveland, OH 44131.
In Canada - CGA No. B149 (latest version), from Canadian Gas
Association Laboratories, 55 Scarsdale Road, Don Mills, Ontario,
Canada M3B 2R3. Also, Canadian Electrical Code, C 22.1, from
Canadian Standards Association, 5060 Spectrum Way, Suite
100, Mississauga, Ontario, Canada L4W 5N6.
Code for the Installation of Heat Producing Appliances (latest
version) from American Insurance Association, 85 John Street,
New York, NY 11038.
The latest version of the National Electrical Code, NFPA No. 70.
NOTE: The gas manifold and controls met safe lighting and
other performance criteria when undergoing tests specied in
ANSI Z21.10.3 - latest edition.
having statutory authority. In some circumstances, the property
owner or his/her agent assumes the role, and at government
installations, the commanding ocer or departmental ocial
may be the AHJ.
NOTE: HTP, Inc. reserves the right to modify product technical
specications and components without prior notice.

LP-325 Rev. 4.4.17
4
H. Wiring of an Appliance Alarm (Optional) 29
I. Wiring of the Cascade System Communication Bus 30
J. Cascade Master Pump and Sensor Wiring 30
K. Cascade Follower Pump and Sensor Wiring 30
L. Internal Wiring Diagram 32
Part 7 - Gas Connections 33
A. Gas Piping 33
B. Gas Table 33
C. Gas Valve 34
Part 8 - Start-Up Preparation 35
A. Check / Control Water Chemistry 35
B. Check for Gas Leaks 35
C. Freeze Protection (When Used) 35
D. Fill and Test Water System 36
E. Purge Air from the Hydronic System 36
F. Check Thermostat Circuit(s) 36
G. Final Checks Before Starting Appliance 36
H. Condensate Removal 36
Part 9 - Start-Up Procedure 37
A. Operating Instructions 37
B. Cascade System 37
C. Adjusting the Setpoint 37
D. Status Menu 38
E. Purge Air from System 38
Part 10 - Start-Up Procedures for the Installer 38
A. Program Access 38
B. Program System Settings 39
C. Combustion System Test Mode 41
Part 11 - Troubleshooting 41
A. Error and Fault Codes 41
B. Appliance Error 41
C. Appliance Fault 41
D. Displayed Error and Fault Codes 42
Part 12 - Maintenance 44
Part 13 - Shutdown 44
A. Shutdown Procedure 44
B. Vacation Procedure 44
C. Failure to Operate 44
D. Important Notice 44
Part 14 - Installation Checklist 48
Part 15 - Maintenance Report 49
Limited Warranty 51
Maintenance Notes 53
Customer Installation Record Form 54
Table of Contents
Part 1 - General Safety Information 5
A. Improper Combustion 5
B. Gas 5
C. When Servicing the Appliance 5
D. Appliance System 5
E. Freeze Protection and Winterizing 6
F. Water Temperature Adjustment 6
G. High Elevation Installations 6
Part 2 - BeforeYou Start 6
A. What’s in the Box 6
B. How the Appliance Operates 6
C. Optional Equipment 7
Part 3 - Prepare the Appliance 7
A. Locating the Appliance 7
B. Leveling 8
C. Clearances for Service Access 8
D. Residential Garage and Closet Installations 9
E. Exhaust Vent and Intake Pipe 9
1. Direct Vent of Exhaust and Intake 9
2. Power Venting, Indoor Combustion Air in Conned or
Unconned Space 9
F. Carbon Monoxide Detectors 10
G. Prevent Combustion Air Contamination 10
H. Removing an Appliance from a Common Vent System 11
I. Water Chemistry Requirements 11
Part 4 - Piping 13
A. Hydronic Plumbing 13
B. Circulator Pumps 13
C. Backow Preventer 13
D. Expansion Tank 13
E. Relief Valve 14
F. Zoning with Zone Valves 14
G. Zoning with Circulators 14
H. Multiple Appliances 14
I. Indirect Water Heater Scalding 14
J. Fill and Purge Heating System 15
K. Central Heating Applications (All Models) 16
Part 5 - Venting and Condensate Removal 18
A. General 18
B. Approved Materials for Exhaust Vent and Intake Pipe 19
C. Additional Requirements for Installation in Canada 19
D. Exhaust Vent and Intake Pipe Location 20
E. Exhaust Vent and Intake Pipe Sizing 21
F. Longer Vent Runs 21
G. Exhaust Vent and Intake Pipe Installation 21
H. Applications 22
1. Direct Vent Installation of Exhaust and Intake 22
2. Venting Through an Existing System 24
3. Power Venting, Indoor Combustion Air in Conned or
Unconned Space 25
I. Condensate Removal System 27
Part 6 - Wiring 28
A. Field Wiring 28
B. Line Voltage Wiring for Standard Appliance 28
C. Thermostat 28
D. Outdoor Sensor (Optional) 29
E. Indirect Sensor (Optional) 29
F. Optional 0-10 Volt Building Control Signal 29
G. UL353 Low Water Cut-O Kit (Optional) 29

LP-325 Rev. 4.4.17
5
Part 1 - General Safety Information
This appliance is approved for indoor installations only
and is not intended for use as a pool heater. Clearance to
combustible materials: 0” top, bottom, sides, and back.
Appliance must have room for service: 24” front, 24” top, and
5” left side are minimum recommended service clearances.
(A combustible door or removable panel is acceptable front
clearance.) This appliance has been approved for closet
installation and installation on combustible ooring. Do not
install directly on carpeting. Install the appliance in a location
where temperature and pressure relief valve discharge or a
leak will not result in damage to the surrounding area. If such
a location is not available, install an auxiliary catch pan. Use
only Category IV vent systems.
Installer - Read all instructions in this manual before installing.
Perform steps in the given order.
User - This manual is for use only by a qualied heating
installer / service technician. Have this appliance serviced /
inspected annually by a qualied service technician.
FAILURE TO ADHERE TO THE GUIDELINES ON THIS PAGE
CAN RESULT IN SUBSTANTIAL PROPERTY DAMAGE,
SEVERE PERSONAL INJURY, OR DEATH.
NOTE: If the appliance is exposed to the following, do not
operate. Immediately call a qualied service technician.
1. Fire
2. Damage
3. Water
Failure to follow this information could result in property
damage, severe personal injury, or death.
DO NOT USE THIS APPLIANCE IF ANY PART HAS BEEN
SUBMERGED INWATER. Immediately call a qualied service
technician. The appliance MUST BE replaced if it has been
submerged. Attempting to operate a appliance that has been
submerged could create numerous harmful conditions, such
as a potential gas leakage causing a re and/or explosion, or
the release of mold, bacteria, or other harmful particulates
into the air. Operating a previously submerged appliance
could result in property damage, severe personal injury, or
death.
NOTE: Appliance damage due to ood or submersion is
considered an Act of God, and IS NOT covered under product
warranty.
NOTE: Obey all local codes. Obtain all applicable permits
before installing the appliance.
NOTE: Install all system components and piping in such a
manner that does not reduce the performance of any re
rated assembly.
Altering any appliance with parts not manufactured by HTP,
Inc. WILL INSTANTLY VOID the appliance warranty and could
result in property damage, personal injury, or death.
Do not use this appliance for anything other than its intended
purpose (as described in this manual). Doing so could result in
property damage and WILL VOID product warranty.
High heat sources (sources generating heat 100oF / 37oC or
greater, such as stove pipes, space heaters, etc.) may damage
plastic components of the appliance as well as plastic vent pipe
materials. Such damages ARE NOT covered by warranty. It is
recommended to keep a minimum clearance of 8” from high
heat sources. Observe heat source manufacturer instructions,
as well as local, state, provincial, and national codes, laws,
regulations and ordinances when installing this appliance and
related components near high heat sources.
A. Improper Combustion
Do not obstruct the ow of combustion and ventilating air.
Adequate air is necessary for safe operation. Failure to keep the
exhaust vent and combustion air intake clear of ice, snow, or
other debris could result in property damage, serious personal
injury, or death.
B. Gas
Should overheating or gas supply fail to shut o, turn o the
manual gas control valve to the appliance.
C. When Servicing the Appliance
To avoid electric shock, disconnect electrical supply before
performing maintenance.
NOTE: When inquiring about service or troubleshooting,
reference the model and serial numbers from the appliance
rating label.
To avoid severe burns, allow appliance and associated
equipment to cool before servicing.
D. Appliance System
Thoroughly ush the system (without the appliance connected)
to remove sediment. The appliance can be damaged by build-
up or corrosion due to sediment. HTP recommends a suction
strainer in all systems.
Do not use petroleum-based cleaning or sealing compounds in
a water heating system. Gaskets and seals in the system may be
damaged. This can result in substantial property damage.
Do not use “homemade cures” or “patent medicines”. Damage
to the appliance, substantial property damage, and/or serious
personal injury may result.
Continual fresh make-up water will reduce appliance life. Mineral
build-up in the heat exchanger reduces heat transfer, overheats
the stainless steel heat exchanger, and causes failure. Addition
Be sure to disconnect electrical power before performing
service. Failure to do so could result in electrical shock, property
damage, serious personal injury, or death.
UNCRATING THE APPLIANCE - Any claims for damage or
shortage in shipment must be led immediately against the
transportation company by the consignee.
The hydronic supply and return connections of this product
are for installation in closed loop systems ONLY! Use of this
product in any manner other than described in this manual
may result in premature product failure, substantial property
damage, personal injury, or death. Damage or failure of
this product (or the system in which it is installed) due to
unauthorized use IS NOT COVERED BY WARRANTY.

LP-325 Rev. 4.4.17
6
Households with small children, disabled, or elderly persons
may require a 120oF or lower temperature setting to prevent
severe personal injury or death due to scalding.
F. Water Temperature Adjustment
If an indirect water heater is going to have a set temperature
above 120oF, you must use an ASSE 1017 rated mixing valve to
avoid severe burns or death from scalding temperatures.
To winterize the appliance, drain the entire system. Pump two
gallons of non-toxic, NSF food grade, FDA rated GRAS (Generally
Recognized As Safe) propylene glycol into the tank. Consult the
glycol manufacturer for specic instructions on concentration
percentage as well as freeze and burst protection methods.
Check the concentration to assure protection is adequate to
protect the bottom of the appliance from freezing.
NOTE: Damages resulting from incorrect installation or from
use of products not approved by HTP, Inc. ARE NOT covered by
warranty.
Approximate Time / Temperature Relationships in Scalds
120oF More than 5 minutes
125oF 1 1/2 to 2 minutes
130oF About 30 seconds
135oF About 10 seconds
140oF Less than 5 seconds
145oF Less than 3 seconds
150oF About 1 1/2 seconds
155oF About 1 second
Table 1 - Approximate Time / Temperature Relationships in Scalds
Part 2 - Before You Start
B. How the Appliance Operates
Condensing Technology maximizes eciency by measuring
the needs of your heating system through the use of sensors
and a control unit. The appliance uses data gathered by
these sensors to intelligently deliver highly ecient hydronic
heating.
Heat Exchanger
Exhaust gas ows through the primary section of the highly
ecient combustion heat exchanger into the secondary heat
exchanger section, where the coldest water on the bottom of
the tank extracts the last residual amount of heat energy from
the gas.
Modulating Combustion System
The combustion system modulates the output of the burner
during operation to match system demand and achieve
the control set point while in operation. The set point can
change by internal or external signals to enhance the overall
performance of the system.
Gas Valve
The gas valve senses suction from the blower, allowing gas to
ow only if combustion air is owing.
Swirl Plate System
The swirl plate on the gas valve controls air and gas ow into
the burner, assuring better mixing for improved combustion.
Combination Top High Temperature Sensor
The control module adjusts appliance ring rate based on the
supply temperature monitored by this sensor.
Bottom Water Temperature Sensor
The control module reduces or increases appliance input
according to the return water temperature measured by this
sensor.
Temperature and Pressure Gauge
Allows the user to monitor system temperature and pressure.
Control
The integrated control system monitors return and supply
water temperature and regulates the unit’s BTU output by
controlling fan speed, delivering only the amount of heated
energy required.
Burner
The metal ber and high grade stainless steel burner uses pre-
mixed air and gas to provide a wide range of ring rates.
Electrical Field Connections with Terminal Strips
The cabinet allows easy access to the clearly marked line
voltage and low voltage terminal strips to facilitate wiring to
the appliance.
Condensate Drain Connection
This is a condensing high eciency appliance with a
Components included with the appliance:
• Intake PVC Tee with Screens
• Exhaust PVC Coupling with Screens
• 30 PSI Temperature and Pressure Relief Valve
• Installation Manual and Warranty
• User’s Information Manual
• Pressure and Temperature Gauge
• Outdoor Sensor (Part # 7250P-319)
A. What’s in the Box
Remove all sides of the shipping crate of the appliance.
E. Freeze Protection and Winterizing
NOTE: Consider piping and installation when determining
appliance location.
Failure of the appliance due to freeze related damage IS NOT
covered by product warranty.
NEVER use any toxic chemical, including automotive, standard
glycol antifreeze, or ethylene glycol made for hydronic (non-
potable) systems. These chemicals can attack gaskets and seals
in water systems, are poisonous if consumed, and can cause
personal injury or death.
of oxygen from make-up water can cause internal corrosion of
system components. Leaks in the appliance or piping must be
repaired at once.
G. High Elevation Installations
Natural gas at high elevation might contain less heating value
than typical 1,000 BTU/cu ft and therefore can cause improper
air / gas mix leading to improper combustion. For natural gas
installations above 3,000 ft, call your gas provider to determine
the heating value of the supplied natural gas.

LP-325 Rev. 4.4.17
7
condensate removal system. Condensate is nothing more
than water vapor derived from combustion products, similar
to that of an automobile when it is initially started. It is very
important that the condensate line slopes away from the
appliance and down to a suitable inside drain.
If the appliance condensate outlet is lower than the drain, use
a condensate removal pump (Part # 554200, available from
HTP). In addition, local authorities may require a condensate
neutralizer to neutralize the condensate. Condensate
neutralizers are made up of lime crystals, marble, or phosphate
chips. Neutralizers can be installed in the eld by the installer
and purchased from HTP (7450P-212).
It is also very important not to expose the condensate line to
freezing temperatures or any type of blockage. Plastic tubing
must be the only material used for the condensate line. Steel,
brass, copper, or other materials will be subject to corrosion
or deterioration. A second vent may be necessary to prevent
condensate line vacuum lock on a long horizontal run. Also,
an increase in pipe size may be necessary to allow condensate
to drain properly. Support of the condensate line may be
necessary to avoid blockage of the condensate ow.
Spark Ignition
The burner ame ignites by applying high voltage to the
system spark electrode. This causes a spark from electrode to
ground.
Outdoor Sensor
When equipped, the outdoor sensor monitors outdoor
temperature and adjusts the set point to provide greater
eciency.
(Optional) Indirect Tank Sensor – Indirect Priority
To control the temperature of low temperature heating
circuits when using an indirect red water appliance, a
thermostatic mixing valve is required. Failure to install a
thermostatic mixing valve could result in property damage,
severe personal injury, or death.
The indirect sensor allows the installer to operate the
appliance to satisfy two temperatures: one for central heating
and the other for a domestic hot water heater. This allows the
user to increase water temperature supplied to the appliance
to recover faster by prioritizing ow at a higher rate than
may be needed for central heating. NOTE: This application
requires two separate circulators.
C. Optional Equipment
Optional equipment available from HTP (and Part #):
• 3” Stainless Steel Vent Termination Kit (V1000)
• 4” Stainless Steel Vent Termination Kit (V2000)
• 2” PVC Concentric Vent Kit (KGAVT0501CVT)
• 3” PVC Concentric Vent Kit (KGAVT0601CVT)
• 3” Polypro Vent Kit (8400P-001)
• 3” Polypro Pipe
(33’ length # 8400P-002, 49.5’ length # 8400P-003)
• System Sensor (7250P-324)
• Indirect Tank Sensor (7250P-325)
• Alarm System (7350P-602) to monitor any failure
• Outdoor Sensor (7250P-319)
• PC Connection Kit (7250P-320)
• Condensate Neutralizer (7450P-212)
Part 3 - Prepare the Appliance
Remove all sides of the shipping crate to allow the appliance to
be moved into its installation location.
COLDWEATHER HANDLING - If the appliance has been stored
in a very cold location (BELOW 0oF) before installation, handle
with care until the components come to room temperature.
Failure to do so could result in damage to the appliance.
Carefully consider installation when determining appliance
location. Please read the entire manual before attempting
installation. Failure to properly take factors such as appliance
venting, piping, condensate removal, and wiring into account
before installation could result in wasted time, money, and
possible property damage and personal injury.
This appliance is certied for indoor use only. DO NOT INSTALL
OUTDOORS. Outdoor installations ARE NOT covered by
warranty. Failure to install the appliance indoors could result in
property damage, severe personal injury, or death.
A. Locating the Appliance
Incorrect ambient conditions can lead to damage to the
heating system and put safe operation at risk. Ensure that the
installation location adheres to the information included in
this manual. Failure to do so could result in property damage,
serious personal injury, or death. Failure of an appliance or
components due to incorrect operating conditions IS NOT
covered by product warranty.
• UL 353 Compliant Low Water Cut-O Interface Kit with
Manual Reset (7350P-601)
• Vision 2 Temperature Mixing Control (7250P-322)
NOTE: When using an optional system sensor, pipe insulation
must be wrapped around it to improve temperature
measurement accuracy and increase overall system eciency.
This appliance must be installed upright in the vertical position
as described in this manual. DO NOT attempt to install this
appliance in any other orientation. Doing so will result in
improper appliance operation and property damage, and could
result in serious personal injury or death.
1. Installation Area (Mechanical Room) Operating Conditions
• Ensure ambient temperatures are higher than 32oF / 0oC
and lower than 104oF / 40oC
• Prevent the air from becoming contaminated by the
products, places, and conditions listed in this manual
• Avoid continuously high levels of humidity
• Never close existing ventilation openings
• Ensure a minimum 1” clearance around hot water and
exhaust vent pipes
• NOTE: To prevent condensing in the fan, it is
recommended to avoid prolonged exposure to
temperatures below 45oF

LP-325 Rev. 4.4.17
8
This appliance has a condensate disposal system that may
freeze if exposed to sustained temperatures below 32oF.
Precautions should be taken to protect the condensate trap and
drain lines from sustained freezing conditions. Failure to take
precautions could result in property damage, severe personal
injury, or death.
Failure to keep the appliance area clear and free of combustible
materials, liquids, and vapors can result in substantial property
damage, severe personal injury, or death.
High heat sources (generating heat 100oF / 37oC or greater,
such as boiler ue pipes, space heaters, etc.) may damage
plastic components of the appliance as well as plastic vent pipe
materials. Such damages ARE NOT covered by warranty. It is
recommended to keep a minimum clearance of 8” from high
heat sources. Observe heat source manufacturer instructions,
as well as local, state, provincial, and national codes, laws,
regulations, and ordinances when installing this appliance and
related components near high heat sources.
Locate the appliance where any leakage from the relief valve,
related piping, tank, or connections will not result in damage to
surrounding areas or lower oors of the building. The appliance
should be located near a oor drain or installed in a drain pan.
Leakage damages ARE NOT covered by warranty.
The service life of the appliance’s exposed metallic surfaces,
such as the casing, as well as internal surfaces, such as the heat
exchanger, are directly inuenced by proximity to damp and
salty marine environments. In such areas higher concentration
levels of chlorides from sea spray coupled with relative humidity
can lead to degradation of appliance components. In these
environments, appliances must not be installed using direct
vent systems which draw outdoor air for combustion. Such
appliances must be installed using room air for combustion.
Indoor air will have a much lower relative humidity, and hence
potential corrosion will be minimized.
Failure of the appliance or components due to incorrect
operating conditions IS NOT covered by product warranty.
4. Gas control system components must be protected from
dripping water during operation and service.
5. If the appliance is to replace an existing appliance, check for
and correct any existing system problems, such as:
• System leaks
• Location that could cause the system and appliance to
2. Check for nearby connections to:
• System water piping
• Venting connections
• Gas supply piping
• Electrical power
• Condensate drain
3. Check area around appliance. Remove any combustible
materials, gasoline, and other ammable liquids.
B. Leveling
In order for the condensate to properly ow out of the
collection system, the area where you locate the appliance
must be level. Location must also fully support the weight of
the lled appliance.
C. Clearances for Service Access
All appliances eventually leak. It is recommended to install
a catch pan beneath the appliance. This catch pan should be
sized with a maximum depth of 2”, and a minimum diameter
2” greater than the diameter of the appliance. The catch pan
should empty into an open drain line. This drain line should
be 3/4” ID minimum, piped to an open drain. Failure to follow
these instructions could result in property damage. Such
damages ARE NOT covered by product warranty.
The space must be provided with combustion / ventilation
air openings correctly sized for all other appliances located in
the same space as the appliance. The appliance cover must
be securely fastened to prevent the appliance from drawing
air from the appliance room. This is particularly important if
the appliance is in a room with other appliances. Failure to
comply with the above warnings could result in substantial
property damage, severe personal injury, or death.
freeze and leak
• Incorrectly sized expansion tank
6. Clean and ush system when reinstalling a appliance.
NOTE: When installing in a zero clearance location, it may
not be possible to read or view some product labeling. It is
recommended to make note of the appliance model and serial
number.

LP-325 Rev. 4.4.17
9
Figure 1 - Recommended Service Clearances and Catch Pan
Dimensions
NOTE: If you do not provide the minimum clearances shown
in Figure 1 it might not be possible to service the appliance
without removing it from the space.
NOTE: A combustible door or removable panel is acceptable
front clearance.
Precautions
If the appliance is located in a residential garage, per ANSI
Z223.1:
• Install the appliance burner and ignition devices a
minimum of 18” above the oor of the garage. This will
ensure the burner and ignition devices are well o the
oor.
• When raising the appliance ensure the entire bottom
and fully lled weight of the appliance are fully
supported.
• Locate or protect the appliance so it cannot be
damaged by a moving vehicle.
D. Residential Garage and Closet Installations
Check with your local Authority Having Jurisdiction for
requirements when installing the appliance in a garage or
closet. Please read the entire manual before attempting
installation. Failure to properly take factors such as venting,
piping, condensate removal, and wiring into account before
installation could result in wasted time, money, and possible
property damage and personal injury.
The space must be provided with correctly sized combustion/
ventilation air openings for all other appliances located in the
space with the appliance. For power venting installations using
room air for combustion, refer to the venting section, this
manual, for descriptions of conned and unconned spaces. Do
not install the appliance in an attic. Failure to comply with these
warnings could result in substantial property damage, severe
personal injury, or death.
E. Exhaust Vent and Intake Pipe
The appliance is rated ANSI Z21.10.3 Category IV (pressurized
vent, likely to form condensate in the vent) and requires a special
vent system designed for pressurized venting.
NOTE: The venting options described here (and further
detailed in the Venting section, this manual) are the lone
venting options approved for this appliance. Failure to
vent the appliance in accordance with the provided venting
instructions will void the warranty.
Failure to vent the appliance properly will result in serious
personal injury or death.
Do not attempt to vent this appliance by any means other than
those described in this manual. Doing so will void the warranty
and may result in severe personal injury or death.
Vents must be properly supported. Appliance exhaust and
intake connections are not designed to carry heavy weight.
Vent support brackets must be within 1’ of the appliance and
the balance at 4’ intervals. Appliance must be readily accessible
for visual inspection for rst 3’ from the appliance. Failure to
properly support vents could result in property damage, severe
personal injury, or death.
The exhaust discharged by this appliance may be very hot.
Avoid touching or other direct contact with the exhaust gases of
the vent termination assembly. Doing so could result in severe
personal injury or death.
1. Direct Vent of Exhaust and Intake
If installing a direct vent option, combustion air must be drawn
from the outdoors directly into the appliance intake and exhaust
must terminate outdoors. There are three basic direct vent
options detailed in this manual: 1. Side Wall Venting, 2. Roof
Venting, and 3. Unbalanced Venting.
Be sure to locate the appliance such that the exhaust vent and
intake piping can be routed through the building and properly
terminated. Dierent vent terminals can be used to simplify and
eliminate multiple penetrations in the building structure (see
Optional Equipment in Venting Section). The exhaust vent and
intake piping lengths, routing, and termination methods must
all comply with the methods and limits given in the Venting
Section, this manual.
When installing a combustion air intake from outdoors, care
must be taken to utilize uncontaminated combustion air. To
prevent combustion air contamination, see Table 2.
2. Power Venting, Indoor Combustion Air in Conned or
Unconned Space
This appliance requires fresh, uncontaminated air for safe
operation and must be installed in a mechanical room where

LP-325 Rev. 4.4.17
10
When drawing combustion air from the outside into the
mechanical room, care must be taken to provide adequate
freeze protection.
Failure to provide an adequate supply of fresh combustion air can
cause poisonous ue gases to enter the living space, resulting
in severe personal injury or death. To prevent combustion air
contamination, see Table 2.
G. Prevent Combustion Air Contamination
Install intake air piping for the appliance as described in the
Venting Section, this manual. Do not terminate exhaust in
locations that can allow contamination of intake air.
Ensure that the intake air will not contain any of the
contaminants in Table 2. Contaminated air will damage the
appliance, resulting in possible substantial property damage,
severe personal injury, or death. For example, do not pipe
intake air near a swimming pool or laundry facilities. These
areas always contain contaminants.
Products to Avoid Areas Likely to Have
Contaminants
Spray cans containing
uorocarbons
Dry cleaning / laundry areas
and establishments
Permanent wave solutions Swimming pools
Chlorinated waxes / cleaners Metal fabrication plants
Chlorine-based swimming pool
chemicals Beauty shops
Calcium chloride used for thawing Refrigeration repair shops
Sodium chloride used for water
softening Photo processing plants
Refrigerant leaks Auto body shops
Paint or varnish removers Plastic manufacturing plants
Hydrochloric or Muriatic acid Furniture renishing areas
and establishments
Cements and glues New building construction
Antistatic fabric softeners used in
clothes dryers Remodeling areas
Chlorine-type bleaches, laundry
detergents, and cleaning solvents Garages and workshops
Adhesives used to fasten building
products
Table 2 - Products and Areas Likely to Have Contaminants
NOTE: DAMAGE TO THE APPLIANCE CAUSED BY
EXPOSURE TO CORROSIVE VAPORS IS NOT COVERED
BY WARRANTY. (Refer to the limited warranty for complete
terms and conditions.)
In the Commonwealth of Massachusetts and As Required by
State and Local Codes:
Installation of Carbon Monoxide Detectors: At the time of
installation or replacement of the vented gas fueled appliance,
the installing plumber or gas tter shall observe that a hard wired
carbon monoxide detector with an alarm and battery back-up is
installed on the oor level where the gas appliance is installed,
unless the appliance is located in a detached, uninhabitable
structure separate from the dwelling, building, or structure used
in whole or in part for residential purposes.
In addition, the installing plumber or gas tter shall observe
that a hard wired carbon monoxide detector with an alarm
and battery back-up is installed on each additional level of
the dwelling, building, or structure served by the vented gas
appliance. It shall be the responsibility of the property owner
to secure the service of qualied licensed professionals for the
installation of hard wired carbon monoxide detectors.
Do not attempt to vent this appliance by any means other
than those described in this manual. Doing so will void the
warranty and may result in severe personal injury or death.
Approved Carbon Monoxide Detectors: Each carbon
monoxide detector as required in accordance with the above
provisions shall comply with NFPA 70 and be ANSI/UL 2034
listed and IAS certied.
F. Carbon Monoxide Detectors
there is adequate combustion and ventilating air. NOTE: To
prevent combustion air contamination, see Table 2.
Combustion air from the indoor space can be used if the space
has adequate area or when air is provided through a duct or
louver to supply sucient combustion air based on the appliance
input. Never obstruct the supply of combustion air to the
appliance. If the appliance is installed in areas where indoor air is
contaminated (see Table 2) it is imperative that the appliance be
installed as direct vent so that all combustion air is taken directly
from the outdoors into the appliance intake connection.
Unconned space is space with volume greater than 50 cubic
feet per 1,000 BTU/hr (4.8 cubic meters per kW) of the total
input rating of all fuel-burning appliances installed in that space.
Rooms connected directly to this space through openings not
furnished with doors are considered part of the space. See
Venting Section for details.
Conned space is space with volume less than 50 cubic feet per
1,000 BTU/hr (4.8 cubic meters per kW) of the total input rating
of all fuel-burning appliances installed in that space. Rooms
connected directly to this space through openings not furnished
with doors are considered part of the space.
When drawing combustion air from inside a conventionally
constructed building to a conned space, such space should be
provided with two permanent openings: one located 6” (15 cm)
below the space ceiling, the other 6” (15cm) above the space
oor. Each opening should have a free area of one square inch
per 1,000 BTU/hr (22cm2/kW) of the total input of all appliances
in the space, but not less than 100 square inches (645cm2).
If the conned space is within a building of tight construction, air
for combustion must be obtained from the outdoors as outlined
in the Venting section of this manual.
a. In the event that the vented gas fueled appliance is
installed in a crawl space or attic, the hard wired carbon
monoxide detector with alarm and battery back-up shall be
installed on the next adjacent oor level.
b. In the event that these requirements cannot be met
at the time of completion of installation, the owner shall
have a period of thirty (30) days to comply with the above
requirements; provided, however, that during said thirty (30)
day period, a battery operated carbon monoxide detector
with an alarm shall be installed.

LP-325 Rev. 4.4.17
11
H. Removing an Appliance from a Common Vent
System
Failure to follow all instructions can result in ue gas spillage
and carbon monoxide emissions, causing severe personal
injury or death.
Do not install the appliance into a common vent with any
other appliance. This will cause ue gas spillage or appliance
malfunction, resulting in possible substantial property
damage, severe personal injury, or death.
When removing an existing appliance, follow the steps below.
1. Seal any unused openings in the common venting system.
2. Visually inspect the venting system for proper size and
horizontal pitch to determine if there is blockage, leakage,
corrosion, or other deciencies that could cause an unsafe
condition.
3. If practical, close all building doors, windows, and
doors between the space in which the appliance remains
connected to the common venting system and other spaces
in the building. Turn on clothes dryers and any appliances
not connected to the common venting system. Turn on any
exhaust fans, such as range hoods and bathroom exhausts,
at maximum speed. Do not operate a summer exhaust fan.
Close all replace dampers.
4. Place in operation the appliance being inspected. Follow the
lighting instructions. Adjust the thermostat so the appliance
will operate continuously.
5. Test for spillage at the draft hood relief opening after 5
minutes of main burner operation. Use the ame of a match
or candle or smoke from a cigarette.
6. After it has been determined that each appliance remaining
connected to the common venting system properly vents
when tested as outlined, return doors, windows, exhaust fans,
replace dampers, and any other gas burning appliances to
their previous condition of use.
7. Any improper operation of the common venting system
should be corrected to conform to the National Fuel Gas
Code, ANSI Z223.1. When resizing any portion of the common
venting system, the system should approach the minimum
size as determined using the appropriate tables in Appendix
G of ANSI Z223.1.
Figure 2 - CO Warning Label
I. Water Chemistry Requirements
Chemical imbalance of the water supply may aect eciency
and cause severe damage to the appliance and associated
equipment. Water quality must be professionally analyzed to
determine whether it is necessary to treat the water. Various
solutions are available to adjust water quality. Adverse water
quality will aect the reliability of the system. In addition,
operating temperatures above 135oF will accelerate the build-
up of lime scale and possibly shorten appliance service life.
Failure of an appliance due to lime scale build-up, low pH, or
other chemical imbalance IS NOT covered by the warranty.
The water must be potable, free of corrosive chemicals, sand,
dirt, and other contaminates. It is up to the installer to ensure
the water does not contain corrosive chemicals or elements that
can damage the heat exchanger. Potable water is dened as
drinkable water supplied from utility or well water in compliance
with EPA secondary maximum contaminant levels (40 CFR Part
143.3). If the water contains contaminants higher than outlined
by the EPA, water treatment is recommended and additional,
more frequent maintenance may be required.
If you suspect that your water is contaminated in any way,
discontinue use of the appliance and contact an authorized
technician or licensed professional.
• Water pH between 6.5 and 8.5
• pH levels below 6.5 can cause an increase in the rate
of corrosion. pH of 8.5 or higher can potentially cause
lime scale build-up
• Maintain water pH between 6.5 and 8.5. Check with
litmus paper or have it chemically analyzed by a local
water treatment company.
• If the pH is not between 6.5 and 8.5, consult a local
water treatment company for solutions.
• Hardness less than 7 grains (120 mg/L) (Water
temperatures of 140oF and greater)
• Hardness levels above the required amounts can lead

LP-325 Rev. 4.4.17
12
to lime scale build-up throughout the system. Water
below 5 grains/gallon (85 mg/L) may be over softened.
• Consult local water treatment companies for unusually
hard water areas (above the required amounts) or
for other treatment solutions if water is being over
softened (below 5 grains/gallon [85 mg/L]).
• Chloride concentration less than 100 ppm (mg/L)
• Do not ll appliance or operate with water containing
chlorides in excess of 100 ppm (mg/L).
• Using chlorinated fresh water should be acceptable as
levels are typically less than 5 ppm (mg/L).
• Do not connect the appliance to directly heat swimming
pool or spa water.
Front View
Top View
Side View
Figure 3 - Appliance Dimensions - NOTE: All Dimensions Are Approximate
• Total Dissolved Solids (TDS) less than 500 ppm
(mg/L)
• Total dissolved solids are minerals, salts, metals, and
charged particles that are dissolved in water.
• The greater the amounts of TDS present, the higher
the corrosion potential due to increased conductivity
in the water.
• If using softened water to ll the appliance, it is
still possible to have high TDS. This water can be
corrosive. Consult local water treatment companies
for other treatment solutions to reduce this eect.
*NOTE: To promote appliance service life, it is strongly
recommended to follow the maintenance procedures in
this manual.

LP-325 Rev. 4.4.17
13
Part 4 - Piping
Failure to follow the instructions in this section WILL VOID the
warranty and may result in property damage, severe personal
injury, or death.
Dielectric unions or galvanized steel ttings must not be
used in a system with this appliance. Doing so WILL VOID the
warranty. Use only copper, brass, or stainless steel ttings.
Teon thread sealant must be used on all connections.
A. Hydronic Plumbing
Use two wrenches when tightening water piping at appliance.
Use one wrench to prevent the appliance return or supply
line from turning. Failure to prevent piping connections from
turning could cause damage to appliance components.
This appliance is designed to function in a closed loop 15 PSI
System. A factory installed low water cut o will ensure that
you have adequate water in the system. We have also included
a T&P gauge which allows the user to monitor system pressure
and outlet temperature from the appliance.
Install the appliance so the gas ignition system components
are protected from water (dripping, spraying, etc.) allowing
clearance for basic service of circulator replacement, valves
and other parts. Observe minimum 1” clearance around all
hot water pipes not protected by non-combustible materials.
On an appliance installed above radiation level, some states
and local codes require a low water cut o device at the time
of installation. If the appliance supplies hot water to heating
coils in air handler units, ow control valves or other devices
must be installed to prevent gravity circulation of appliance
water in the coils during the cooling cycle. Chilled water
medium must be piped in parallel with the appliance.
Basic steps are listed below which will guide you through the
installation of the appliance.
1. Connect the system return marked “Return”.
2. Connect the system supply marked “Supply”.
3. Install purge and balance valve or shut o valve and drain on
system return to purge air out of each zone.
4. Install a back ow preventer on the cold feed make-up
Plumbing of this appliance should only be done by a qualied,
licensed plumber in accordance with all local and national
plumbing codes or any applicable prevailing standards. The
appliance may be connected to an indirect storage tank to
supply domestic hot water. HTP oers 30/45/60/80/119 gallon
size indirect storage tanks in Stainless Steel or 50/80/119 in
Glass Lined construction. These indirect storage tanks will be
directly connected to the supply and return connections.
The building piping system must meet or exceed the piping
requirements in this manual.
The appliance control module uses temperature sensors
to provide both high limit protection and modulating
temperature control. The control module also provides low
water protection by sensing the water level in the appliance.
Some codes/jurisdictions may require additional external
controls.
water line.
5. Install a pressure reducing valve on the cold feed make-
up water line, (15 PSI nominal on the system return). Check
temperature and pressure gauge which should read minimum
pressure of 12 PSI.
6. Install a circulator as shown in piping details (this section).
Make sure the circulator is properly sized for the system and
friction loss.
7. Install an expansion tank on the system supply. Consult
manufacturer instructions for specic information relating to
expansion tank installation. Size the expansion tank for the
required system volume and capacity.
8. Install supply air vent to remove air when commissioning the
appliance.
9. The safety relief valve is supplied with the appliance, and must
be installed on the top ¾” NPT tting marked “T&P”. Pipe the
discharge of the safety relief valve to prevent injury in the event
of pressure relief. Discharge 6” above the drain. Provide piping
that is the same size as the safety relief valve outlet. Never block
the outlet of safety relief valve.
B. Circulator Pumps
DO NOT install automatic air vents on closed type expansion
tank systems. Air must remain in the system and return to the
tank to provide an air cushion. An automatic air vent would
cause air to leave the system, resulting in improper operation
of the expansion tank.
Sizing Space Heat System Piping
1. See piping details in this manual. Special attention must be
paid when connecting an indirect storage tank, as temperature
delivered to low temperature circuits may be higher than
desired. The use of thermostatic mixing valves is required to
protect these circuits.
To control the temperature of low temperature heating circuits
when using an indirect red water heater, a thermostatic
mixing valve is required. Failure to install a thermostatic mixing
valve when using an indirect red water heater could result in
damage the heating circuits. Such damage IS NOT covered by
warranty.
2. Size the piping and components in the space heating system
using recognized design methods.
C. Backow Preventer
Use a backow preventer specically designed for hydronic
installations. This valve should be installed on the cold water ll
supply line per local codes.
D. Expansion Tank
Expansion Tank and Make-Up Water
1. Ensure that the expansion tank is sized to correctly handle
appliance and system water volume and temperature. The
appliance volume is 55 gallons.
Undersized expansion tanks cause system water to be lost from
the relief valve, causing make-up water to be added. Eventual
appliance failure can result due to excessive make-up water
addition. SUCH FAILURE IS NOT COVERED BY WARRANTY.

LP-325 Rev. 4.4.17
14
I. Indirect Water Heater Scalding
This appliance can deliver scalding water. Be careful whenever
using hot water to avoid scalding injury. Certain appliances
such as dishwashers and automatic clothes washers may
require increased water temperatures. By setting the
thermostat on this appliance to obtain the increased water
temperature required by these appliances you may create the
potential for scald injury.
To protect against injury, install the mixing valve included with
this appliance. This valve will reduce point of use discharge
temperatures by mixing cold and hot water in the branch
supply lines.
Table 3 details the relationship of water temperature and
time with regard to scald injury and may be used as a guide
in determining the safest water temperature for your
applications.
H. Multiple Appliances
1. All piping shown is reverse return to assure balanced ow
through the connected appliances.
2. Connect DHW piping to indirect storage water appliance as
shown.
2. The expansion tank must be located as shown in Applications,
this manual, or following recognized design methods. See
expansion tank manufacturer’s instructions for details.
3. Connect the expansion tank on the suction side of the
circulator. Always install the system ll connection at the same
point as the expansion tank connection to the system.
4. Most chilled water systems are piped using a closed type
expansion tank.
Failure to follow the instructions in this section WILL VOID the
warranty and may result in property damage, serious personal
injury, or death.
F. Zoning with Zone Valves
1. Connect appliance to system as shown in the Applications
diagrams. Properly size circulators for friction loss of zone
valves and piping for proper operation.
2. Connect DHW (domestic hot water) piping to indirect
storage water appliance as shown.
G. Zoning with Circulators
1. Connect appliance to system as shown in the Applications
diagrams. Properly size each zone circulator for friction loss of
each zone for proper operation.
2. Install a separate circulator for each zone.
3. Connect DHW piping to indirect storage water appliance as
shown.
Overheated water and high pressures can cause water tank
explosion. A properly sized temperature and pressure relief
valve must be installed in the opening provided on the appliance.
Failure to install a properly sized temperature and pressure
relief valve could result in explosion and property damage,
serious injury, or death.
E. Relief Valve
Install supplied temperature and pressure relief valve. Connect
discharge piping to a safe disposal location, following the
guidelines on the next page. Replacement relief valves are
available. See parts list.
Do not thread a cap or plug into the relief valve or relief valve
line under any circumstances! Explosion and property damage,
serious injury, or death may result.
To avoid water damage or scalding due to relief valve operation:
• Discharge line must be connected to relief valve outlet
and run to a safe place of disposal. Terminate the
discharge line in a manner that will prevent possibility of
severe burns or property damage should the relief valve
discharge.
• Discharge line must be as short as possible and the same
size as the valve discharge connection throughout its
entire length.
• Discharge line must pitch downward from the valve
and terminate at least 6” above the oor drain, making
discharge clearly visible.
• The discharge line shall terminate plain, not threaded,
with a material serviceable for temperatures of 375oF or
greater.
• Do not pipe discharge to any location where freezing
could occur.
• No valve may be installed between the relief valve and
appliance or in the discharge line. Do not plug or place
any obstruction in the discharge line.
• Test the operation of the relief valve after lling and
pressurizing the system by lifting the lever. Make sure
the valve discharges freely. If the valve fails to operate
correctly, immediately replace with a new properly rated
relief valve.
• Test T&P valve at least once annually to ensure the
waterway is clear. If valve does not operate, turn the
appliance “o” and call a plumber immediately.
• Take care whenever operating relief valve to avoid
RE-INSPECTION OF T&P RELIEF VALVES: T&P valves
should be inspected AT LEAST ONCE EVERY THREE
YEARS, and replaced if necessary, by a licensed plumbing
contractor or qualied service technician to ensure that the
product has not been aected by corrosive water conditions
and to ensure that the valve and discharge line have not been
altered or tampered with illegally. Certain naturally occuring
conditions may corrode the valve and its components over
time, rendering the valve inoperative. Such conditions can
only be detected if the valve and its components are physically
removed and inspected. Do not attempt to conduct an
inspection on your own. Contact your plumbing contractor
for a re-inspection to assure continued safety.
FAILURE TO RE-INSPECT THE T&P VALVE AS DIRECTED
COULD RESULT IN UNSAFE TEMPERATURE AND/OR
PRESSURE BUILD-UP WHICH CAN RESULT IN PROPERTY
DAMAGE, SERIOUS PERSONAL INJURY, OR DEATH.
scalding injury or property damage.
FAILURE TO COMPLY WITH THE ABOVE GUIDELINES
COULD RESULT IN FAILURE OF RELIEF VALVE OPERATION,
RESULTING IN POSSIBILITY OF SUBSTANTIAL PROPERTY
DAMAGE, SEVERE PERSONAL INJURY, OR DEATH.

LP-325 Rev. 4.4.17
15
ASSE 1017 or ASSE 1070 temperature limiting or mixing
valves do not eliminate the risk of scalding.
To avoid scalding:
• Set the appliance set point temperature as low as
possible.
• Feel water before bathing or showering.
• If thermostatic valves are required, use devices
specically designed for such purpose. Install these
devices in accordance with instructions provided by
the manufacturer.
Failure to install a temperature limiting or mixing valve and
follow these instructions could result in property damage,
severe personal injury, or death due to scalds.
Approximate Time / Temperature Relationships in Scalds
120oF More than 5 minutes
125oF 1 1/2 to 2 minutes
130oF About 30 seconds
135oF About 10 seconds
140oF Less than 5 seconds
145oF Less than 3 seconds
150oF About 1 1/2 seconds
155oF About 1 second
Table 3 - Approximate Time / Temperature Relationships in Scalds
J. Fill and Purge Heating System
• Attach the hose to either balance or purge hose
connector or drain valve and run hose to nearest drain.
• Close the other side of the balance and purge valve or
the shut o valve after the drain.
• Open rst zone balance and purge or drain valve to let
water ow out the hose. If zone valves are used, open
the valves one at a time manually. (NOTE: You should
check valve manufacturer instruction prior to opening
valves manually, so as not to damage any valves.)
• Manually operate ll valve regulator. When water runs
out of the hose, while it’s connected to the balance and
purge valve or drain you will see a steady stream of
water (without bubbles). Close balance and purge valve
or drain to stop the water from owing. Disconnect the
hose and connect it to next zone to be purged.
• Repeat this procedure for additional zones (one at a
time).
The appliance must be full of water and the system fully
purged BEFORE powering the appliance. When lling the
appliance, open a hot water tap to release air in the tank and
piping. All air has been purged from the system when water
runs freely from the faucets.
Applying power to the appliance when it is not full of water
will damage the heat exchanger, and could result in property
damage, serious personal injury, or death. Such damages
ARE NOT covered by appliance warranty.
For installation that incorporates standing iron radiation and
systems with manual vents at high points, follow above section
and, starting with the nearest manual air vent, open until water
ows out. Then close vent. Repeat procedure, working your way
toward furthest air vent.
NOTE: It may be necessary to install a basket strainer in an older
system where larger amounts of sediment may be present.
Annual cleaning of strainer may be necessary.
Upon completion, make sure that the ll valve is in automatic
position and each zone balance and purge or shut o is in an
open position and zone valves are set for automatic operation.
Use only inhibited propylene glycol solutions which are FDA
RATED AS GRAS and specically formulated for hydronic
systems. Ethylene glycol is toxic and can attack gaskets and
seals used in hydronic systems. Failure to follow the instructions
in this section WILL VOID the warranty and may result in
property damage, severe personal injury, or death.
Glycol in hydronic
applications includes
inhibitors that prevent
it from attacking
metallic system
components. Make
certain that system
uid is checked for
the correct glycol
concentration and
inhibitor level.
The glycol solution
should be tested at
least once a year, or as
recommended by the
glycol manufacturer.
Anti-freeze solutions
expand more than
water. For example: A
50% by volume glycol
solution expands 4.8%
in volume during a temperature increase from 32 to 180oF, while
water expands 3% over the same temperature rise. Allowances
must be made for expansion in system design.
A 30% mixture of glycol results in a BTU output loss of 15% with
a 5% increase in head against the system circulator.
A 50% glycol mixture results in a BTU output loss of 30% with a
50% increase in head against the system circulator.
It is highly recommended that you carefully follow glycol
manufacturer recommended concentrations, expansion
requirements, and maintenance recommendations (pH additive
break down, inhibitor reduction, etc.) You must carefully gure
the additional friction loss in the system as well as the reduction
in heat transfer coecients.

LP-325 Rev. 4.4.17
16
K. Central Heating Applications (All Models)
NOTES:
1. This drawing is meant to show
system piping concept only.
Installer is responsible for all
equipment & detailing required
by local codes.
2. The minimum pipe size for
connecting a SuperStor Ultra
Indirect Water Appliance is 1-inch.
3. The minimum pipe size for
connecting the appliance is 1.25-
inch
4. Circulators are shown with
isolation anges and integral
check valves. The alternative is
standard anges with full port ball
valves and a separate ow check
valve. Purge valves can be used
with the circulator anges as an
alternative.
5. The anti-scald mixing valve
is recommended if the DHW
temperature is set above the
factory setting of 119°F.
6. Install a minimum of 12
diameters of straight pipe
upstream of all circulators.
7. Winterization: When
winterizing, put a drain valve
on both the supply and return
between the union and the shut-
o connection.
8. If a backow
preventer or no return
valve is installed, a
thermal expansion tank
is required on the cold
water inlet between the
water heating appliance
and the backow
preventer.
Figure 4 - Central Heating
Figure 5 - Appliance with Indirect Water Heater

LP-325 Rev. 4.4.17
17
NOTES:
1. This drawing is meant to show system piping concept only.
Installer is responsible for all equipment & detailing required by local codes.
2. The minimum pipe size for connecting a SuperStor Ultra Indirect Water Appliance is 1-inch.
3. The minimum pipe size for connecting the appliance is 1.25-inch
4. Circulators are shown with isolation anges and integral check valves. The alternative is standard anges with full port ball valves and a
separate ow check valve. Purge valves can be used with the circulator anges as an alternative.
5. The anti-scald mixing valve is recommended if the DHW temperature is set above the factory setting of 119°F.
6. Install a minimum of 12 diameters of straight pipe upstream of all circulators.
7. Winterization: When winterizing, put a drain valve on both the supply and return between the union and the shut-o connection.
8. If a backow preventer or no return valve is installed, a thermal expansion tank is required on the cold water inlet between the water heating
appliance and the backow preventer.
Figure 6 - Cascaded System

LP-325 Rev. 4.4.17
18
Part 5 - Venting and Condensate Removal
The appliance must be vented as detailed in this section. Ensure
exhaust vent and intake piping complies with these instructions
regarding vent system. Inspect nished exhaust vent and intake
piping thoroughly to ensure all joints are well secured, airtight,
and comply with all applicable code requirements, as well as the
instructions provided in this manual. Failure to properly install
the vent system will result in severe personal injury or death.
A. General
This appliance is certied as a “Category IV” appliance and
requires a special venting system. The vent system will operate
with a positive pressure in the pipe. Exhaust gases must be
piped directly outdoors using the vent materials and rules
outlined in these instructions. Do not connect vent connectors
serving appliances vented by natural draft into any portion of
mechanical draft systems operating under positive pressure.
Follow the venting instructions carefully. Failure to do so will
result in substantial property damage, severe personal injury,
or death.
1. Installation should be made in accordance with the regulations
of the Authority Having Jurisdiction, local code authorities, and
utility companies which pertain to this type of water heating
equipment.
2. Install the venting system in accordance with these
instructions and with the National Fuel Gas Code, ANSI Z223.1/
NFPA 54, CAN/CGA B149, and / or applicable provisions of local
building codes.
3. This appliance must be vented with materials, components,
and systems listed and approved for Category IV appliances.
Exhaust and intake are to be piped separately. This appliance
cannot share a common exhaust or intake with multiple
appliances. Failure to follow these instructions will result in
substantial property damage, severe personal injury, or death.
NOTE: To avoid contamination often contained in indoor air, it
is best to pipe all intake combustion air directly to the outdoors.
NOTE: If exhaust vent pipe system passes through an unheated
space such as an alcove or attic, the space must be heated.
Improper seating of vent pipe gaskets can cause eventual
gasket failure and exhaust gas leakage. Ensure the exhaust vent
pipe is properly beveled and seated before insertion into the
ue adapter. Failure to do so could result in property damage,
severe personal injury, or death.
Due to the extreme ammability of most glues, cements,
solvents, and primers used to join plastic exhaust vent and
intake pipes, explosive solvent vapors must be cleared from
all vent piping before start-up. Avoid using excess cement or
primer, as this may pool in the vent pipes. Vent assemblies
should be allowed to cure for a period of at least 8 hours before
powering a connected appliance. Failure to follow these
instructions will result in substantial property damage, severe
personal injury, or death. It is the installers’ responsibility to
understand the hazards associated with explosive solvents
and take the necessary precautions to avoid these risks.
CPVC, Polypropylene, or Stainless Steel pipe material MUST
be used for the rst 3 feet of the vent run if the exhaust vent
passes through an enclosed space greater than 6”, such
as a wall. The balance of the vent run can be installed with
standard Schedule 40 PVC pipe. Failure to comply with this
warning could result in property damage, severe personal
injury, or death.
Exhaust vent adaptors are not designed as load-bearing
devices, and must not be used to support exhaust vent piping.
All vent pipes must be properly connected, supported, and
the exhaust vent must be pitched a minimum of 1/4” per foot
back to the appliance to allow drainage of condensate. Failure
to properly support vent piping and follow the information
in this statement could result in product damage, severe
personal injury, or death.

LP-325 Rev. 4.4.17
19
B. Approved Materials for Exhaust Vent and Intake Pipe
• The exhaust and intake components installed with this heater must be used for near heater piping BEFORE transitioning
to the approved materials listed above. DO NOT REMOVE these installed components. Doing so WILL VOID heater
warranty.
• PVC / CPVC pipe and ttings of the same diameter are considered interchangeable.
• Use of cellular core pipe PVC (ASTM F891), cellular core CPVC, or Radel® (polyphenysulfone) in nonmetallic venting
systems is prohibited.
• DO NOT connect PVC/CPVC to Polypropylene without an approved vent connector.
• Any transition to Polypropylene MUST be done in the vertical within ve (5) feet of the appliance.
• When installing AL29-4C vent piping, install a PVC-to-stainless adapter at the heater vent connection, and at the
termination when using a PVC termination kit. DO NOT mix AL29-4C piping from dierent manufacturers unless using
adapters specically designed for the purpose by the manufacturer.
• Covering non-metallic vent pipe and ttings with thermal insulation is prohibited.
• A double wall vent may be used when using stainless steel vent material in a freezing climate.
• *PVC-DWV may be used for air intake applications ONLY.
• Contact the venting material manufacturer if there is any question about the applicability of the proposed venting
material.
Failure to follow these directions will result in substantial property damage, severe personal injury, or death.
DO NOT mix components from dierent venting systems.
The vent system could fail, causing leakage of ue products
into the living space. Use only the approved pipe and tting
materials, and primer and cement specically designed for
the material used, as listed in the above table. Failure to do
so could result in property damage, serious injury, or death.
Table 4 - Approved Materials for Exhaust Vent and Intake Pipe
High heat sources (generating heat 100oF / 37oC or greater,
such as boiler ue pipes, space haters, etc.) may damage
plastic components of the appliance as well as plastic vent
pipe materials. Such damages ARE NOT covered by warranty.
It is recommended to keep a minimum clearance of 8” from
high heat sources. Observe heat source manufacturer
instructions, as well as local, state, provincial, and national
codes, laws, regulations, and ordinances when installing this
appliance and related components near high heat sources.
NOTE: The use of double-wall vent or insulated material for
the combustion air intake pipe is recommended in cold cli-
mates to prevent the condensation of airborne moisture in
the incoming combustion air.
C. Additional Requirements for Installation in Canada
1. Installations must be made with a vent pipe system certied
to ULC-S636. IPEX is an approved vent manufacturer in Canada
supplying vent material listed to ULC-S636. Additionally,
you may use AL29-4C stainless steel venting to comply with
Canadian requirements.
2. The rst three (3) feet of vent pipe from the appliance ue
outlet must be readily accessible for visual inspection. 3.
The components of the certied vent system must not be
interchanged with other vent systems or unlisted pipe / ttings.
You must not use “B” vent in an exhaust application. “B” vent
is for intake applications ONLY. Using “B” vent in an exhaust
application will result in serious injury or death.
Item Material Standards for Installation In:
United States Canada
Exhaust Vent or Intake
Pipe and Fittings
PVC Schedule 40/80 ANSI / ASTM D1785 PVC, CPVC, and PP Venting Must
be ULC-S636 Certied. IPEX is
an approved manufacturer in
Canada.
PVC-DWV* ANSI / ASTM D2665
CPVC Schedule 40/80 ANSI / ASTM F441
Polypropylene UL-1738 or ULC-S636
Stainless Steel AL29-4C Certied for Category IV and Direct Vent Appliance Venting
Pipe Cement PVC ANSI / ASTM D2564 IPEX System 636 Cements and
Primers
CPVC ANSI / ASTM F493
Pipe Primer PVC / CPVC ASTM F656
It is required to insert the provided exhaust and intake screens
into the vent terminations to prevent blockage caused by
debris or birds. Failure to keep terminations clear could result in
property damage, severe personal injury, or death.

LP-325 Rev. 4.4.17
20
D. Exhaust Vent and Intake Pipe Location
Figure 7 - Exit Terminals for Direct Vent Systems - ANSI Z223.1 / NFPA 54 for US and CAN/CSA B149.1 for Canada
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LP-179-CC
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CLOSED
OPERABLE
FIXED
03/28/17
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DETAIL
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INSIDE CORNER
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EExhaust Vent Terminal IIntake Pipe Terminal Area Where Intake Terminal Is Not Permitted
The building owner is responsible for keeping the exhaust
and intake terminations free of snow, ice, or other potential
blockages, as well as scheduling routing maintenance. Failure
to keep the vent piping terminations clear and properly
maintain the heater could result in property damage, severe
personal injury, or death.
For each oor containing bedroom(s), a carbon monoxide
detector and alarm shall be placed in the living area outside
the bedrooms, as well as in the room that houses the heater.
Detectors and alarms shall comply with NFPA 720 (latest
edition). Failure to comply with these requirements could
result in product damage, severe personal injury, or death.
DESCRIPTION US CANADA
AClearance above grade, veranda, porch, deck, or balcony 1 foot (30 cm)
BClearance to window or door that may be opened
Direct Vent 1 foot
3 feet (91 cm)
Power Vent 4 ft below or to side of
opening; 1 ft above opening
CClearance to permanently closed window *
DVertical clearance to ventilated sot located above the terminal within a
horizontal distance 2 feet (61 cm) from the center line of the terminal *
EClearance to unventilated sot *
FClearance to outside corner *
GClearance to inside corner *
HClearance to each side of center line extended above meter / regulator
assembly *
IClearance to service regulator vent outlet *
Above a regulator
within 3 feet (91 cm)
horizontally of the
vertical center line of
the regulator vent outlet
to a maximum vertical
distance of 15 ft (4.5 m)
JClearance to nonmechanical air supply inlet to building or
the combustion air inlet to any other appliance
Direct Vent 1 foot
3 feet (91 cm)
Power Vent 4 ft below or to side of
opening; 1 ft above opening
KClearance to mechanical air supply inlet 3 feet above if within 10 feet
horizontally 6 feet (1.83 m)
LClearance above paved sidewalk or paved driveway located
on public property
Direct Vent *7 feet (2.13 m)
Power Vent 7 feet (2.13 m)
MClearance under veranda, porch deck, or balcony *1 foot (30 cm)
Table 5 - Vent Termination Clearances - *NOTE: For clearances not specied in ANSI Z223.1 / NFPA 54 for US and CAN/CSA B149.1 for
Canada, please use clearances in accordance with local installation codes and the requirements of the gas supplier.