HTP Versa Hydro PHE130 Series Installation manual

Versa Hydro
Combined Appliances
Installation
Start-Up
Maintenance
Parts
Warranty
PHE130 / PHE199 Models*
* “LP” Denotes Propane Gas Operation
“S”Denotes Solar Models
“SNHX” Denotes Solar Models without Heat Exchanger
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.
The manufacturer 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-314 Rev. 012 Rel. 003 Date 9.27.19
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.
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.
This Manual For Use With Appliances
Manufactured After
April 10, 2017

LP-314 Rev. 012 Rel. 003 Date 9.27.19
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 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 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-314 Rev. 012 Rel. 003 Date 9.27.19
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 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
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.
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.
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 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: The manufacturer reserves the right to modify product technical
specications and components without prior notice.

LP-314 Rev. 012 Rel. 003 Date 9.27.19
4
D. Auxiliary Connections 14
E. Temperature and Pressure Relief Valve for DHW 14
F. Backow Preventer 14
G. Potable Expansion Tank 14
H. Hydronic Heating Module Piping 15
I. Pressure Relief Valve for the Hydronic System 15
J. Hydronic Expansion Tank and Make-Up Water 15
K. Hydronic Heating Module System Piping 15
L. Hydronic Heating Module Output 15
M. Applications 18
N. Filling the Appliance 20
Part 5 - Venting 20
A. General 20
B. Approved Materials for Exhaust Vent and Intake Pipe 21
C. Additional Requirements for Installation in Canada 21
D. Exhaust Vent and Intake Pipe Location 22
E. Exhaust Vent and Intake Pipe Sizing 23
F. Longer Vent Runs 23
G. Exhaust Vent and Intake Pipe Installation 23
H. Applications 24
1. Direct Vent Installation of Exhaust and Intake 24
2. Venting Through an Existing System 26
3. Power Venting, Indoor Combustion Air in Conned or Unconned
Space 27
Part 6 - Condensate Removal 29
Part 7 - Wiring 29
A. Field Wiring 29
B. Line Voltage Wiring 29
C. Low Voltage Wiring 29
D. Alarm Connections 30
E. Optional 0-10 Volt Building Control Signal 30
F. Customer Connection Board 31
G. Internal Wiring Diagram 32
Part 8 - Gas Connections 34
A. Gas Pipe Sizing Tables 34
1. Gas Pipe Sizing 34
2. Natural Gas Pipe Sizing 34
3. LP (Liquid Propane) Gas Pipe Sizing 35
B. Gas Piping Requirements 35
C. Gas Valve 35
D. Checking Gas Pressure at the Appliance for Proper Operation
36
Part 9 - Start-Up Preparation 36
A. Fill and Purge DHW 36
B. Fill and Purge Hydronic Heating Loop 36
C. Purge Air from Hydronic Heating Module 36
D. Using the Control to Assist in Purging System Loops 37
E. Programming the Total System Control 37
Part 10 - Start-Up Procedures for the Installer 38
A. Navigation of the Display 38
B. Programming the Control 39
C. Programming the System Setting 39
D. System Setting Program Navigation 39
E. Control Status Menu 41
F. Resetting the Maintenance Schedule 42
G. Test Mode 42
Part 11 - Troubleshooting 42
A. Error and Fault Codes 42
B. Appliance Error 42
C. Appliance Fault 42
D. User Interface Display 43
Part 12 - Maintenance 46
Part 13 - Shutdown 47
A. Shutdown Procedure 47
B. Vacation Procedure 47
C. Failure to Operate 47
D. Important Notice 47
Table of Contents
Part 1 - General Safety Information 5
A. Improper Combustion 5
B. Gas 5
C. When Servicing the Appliance 5
D. Appliance Water 5
E. Freeze Protection 5
F. High Elevation Installations 6
G. Water Temperature Adjustment 6
Part 2 - Before You 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 8
E. Exhaust Vent and Intake Pipe 8
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 9
G. Prevent Combustion Air Contamination 9
H. Removing an Appliance from a Common Vent System 10
I. Water Chemistry Requirements 10
Part 4 - Domestic Hot Water and Hydronic Piping 12
A. Plumbing 12
1. System Domestic Water Piping 12
2. Appliance Domestic Water Piping 12
B. Scalding 12
C. Mixing Valve Installation 13
From the Uniform Plumbing Code 2000 - Section 510 -
Protection From Damage
1. Appliances generating a glow, spark or ame capable of igniting
ammable vapors may be installed in a garage, provided the pilots,
burners or heating elements and switches are at least eighteen (18)
inches (457 mm) above the oor level.
2. Where such appliances installed within a garage are enclosed
in a separate, approved compartment having access only from
outside of the garage, such appliances may be installed at oor level
provided the required combustion air is also taken from the exterior
of the garage. Fuel burning appliances having sealed combustion
chambers need not be elevated.
3. All appliances installed in areas where they may be subjected to
mechanical damage shall be suitably guarded against such damage
by being installed behind adequate barriers or by being elevated or
located out of the normal path of a vehicle using any such garage.
4. In seismic zones 3 and 4, appliances shall be anchored or strapped
to resist horizontal displacement due to earthquake motion.
Strapping shall be at points within the upper one-third (1/3) and
lower one-third (1/3) of its vertical dimensions. At the lower point, a
minimum distance of four (4) inches (102 mm) shall be maintained
above the controls with the strapping.
5. An appliance supported from the ground shall rest on level
concrete or other approved base extending not less than three (3)
inches (76 mm) above the adjoining ground level.
6. When an appliance is located in an attic, attic-ceiling assembly,
oor-ceiling assembly, or oor-suboor assembly where damage
may result from a leaking appliance, a watertight pan of corrosion
resistant materials shall be installed beneath the appliance with
a minimum three-quarter (3/4) inch (20 mm) diameter drain to an
approved location.

LP-314 Rev. 012 Rel. 003 Date 9.27.19
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 and 12”sides 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: 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.
Part 14 - Installation Checklist 48
Part 15 - Maintenance Report 49
Part 16 - Replacement Parts 51
Limited Warranty 54
Maintenance Notes 56
Customer Installation Record Form 57
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 IN WATER. 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.
Altering any HTP, Inc. appliance with parts not manufactured by
HTP, Inc. WILL INSTANTLY VOID the appliance warranty and could
result in property damage, personal injury, or death.
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.
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.
D. Appliance Water
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.
E. Freeze Protection
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.
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. UNCRATING THE APPLIANCE - Any claims for damage or shortage
in shipment must be led immediately against the transportation
company by the consignee.

LP-314 Rev. 012 Rel. 003 Date 9.27.19
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.
G. Water Temperature Adjustment
If the appliance 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.
F. 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.
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
B. How the Appliance Operates
The Versa Hydro with Total System Control provides high eciency
central heating and domestic hot water from one appliance. Total
System Control manages system needs, ensuring maximum comfort
and ecient operation. Some features of the appliance are:
Stainless Steel Water Storage Tank
The storage tank is constructed of 316L stainless steel to provide
maximum corrosion resistance. Water blown foam insulation and a
plastic jacket provide superior insulation, allowing no more than ½
degree heat loss per hour.
High Eciency Heat Exchanger
The 90/10 copper nickel heat exchanger provides highly ecient
energy transfer. Hot gases from the primary circuit heat the combustion
walls. The walls transfer heat directly into the domestic water. The
secondary circuit then transfers the last bit of energy to the bottom
of the tank, where hot gases are converted to water vapor, giving the
appliance a combustion eciency of 98% and thermal eciency of up
to 96%.
Components included with the appliance:
• Intake PVC Tee with Screens
• Exhaust PVC Coupling with Screens
• Temperature and Pressure Relief Valve
• Installation Manual and Warranty
• User’s Information Manual
• Solar Addendum (S Models Only)
• Outdoor Sensor (Part # 7250P-319)
• Mixing Valve (7100P-315)
A. What’s in the Box
Part 2 - Before You Start
Remove all sides of the shipping crate of the appliance.
Modulating Combustion System
The modulating combustion system regulates ring rate based on
heat demand. Total System Control monitors tank operation, system
parameters, and controls the ring rate of the burner, providing only
the energy required to satisfy both domestic hot water and central
heating needs.
Total System Control
Total System Control automatically manages the central heating
and domestic hot water systems through the use of sensors.
These sensors monitor inputs (such as outdoor temperature, tank
temperature, and heating module outlet temperature) providing
data that allows accurate control of the entire system. You may
choose to use the control’s factory default settings or reprogram
system parameters to provide design exibility.
Hydronic Heating Module
The hydronic heating module connects to the storage tank through
two dip tubes. The rst dip tube draws heated water from the top
of the storage tank and circulates it through a brazed plate heat
exchanger to transfer the water’s stored energy to the hydronic
side of the plate. Once the energy is transferred, the water returns
through the second dip tube to a lower section of the storage tank
to continue circulating. A stainless steel circulator pump modulates
output, varying ow through the brazed plate heat exchanger
to meet domestic hot water and central heating demand. An
outlet sensor provides feedback to the control to assure accurate
temperature control.
Venting System
This appliance must be exhausted to the outdoors. Use only the
approved venting materials outlined in the Venting section of this
manual. Vent size can vary from 2”to 3”depending on the appliance
input rate. Special attention should be taken when selecting vent
location. Vents can run horizontally or vertically, depending on
system design, and should be supported as shown in the Venting
section of this manual.
Burner
The burner is constructed of high grade stainless steel and uses pre-
mixed air and gas to provide a wide range of ring rates.
Condensate Drain Connection
This is a condensing high eciency appliance with a 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 is ignited by applying high voltage to the system
spark electrode. This causes a spark from electrode to ground.
Outdoor Sensor
Monitors outdoor temperature and adjusts the set point to provide
greater eciency.

LP-314 Rev. 012 Rel. 003 Date 9.27.19
7
Part 3 - Prepare the Appliance
Remove all sides of the shipping crate to allow the appliance to be
moved into its installation location.
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)
• Alarm System (7350P-602) to monitor any failure
• Outdoor Sensor (7250P-319)
• PC Connection Kit (7250P-320)
• Condensate Neutralizer (7450P-212)
• Solar Kit (7100P-220) applies to Solar models only
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.
COLD WEATHER 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
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
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.
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.
• NOTE: To prevent condensing in the fan, it is recommended to
avoid prolonged exposure to temperatures below 45oF
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.
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.
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.
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.
All appliances eventually leak. 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. Any appliance should be installed in such a manner that if it
should leak the resulting ow of water will not cause damage to the
area in which it is installed. National Plumbing codes require a drain
pan for any appliance installation. This drain pan should be sized with
a maximum depth of 2”, and a minimum diameter 2”greater than the
diameter of the appliance. The drain pan should empty into an open
drain line. This drain line should be 3/4” ID minimum, piped to an
open drain. Leakage damages ARE NOT covered by warranty. Failure
to install a drain pan is the sole responsibility of the owner and/or
installer. Reference UPC 2000 (Uniform Plumbing Code) Section 510
- Protection from Damage or IPC 200 (International Plumbing code)
Section 504 - Safety Devices. Leakage damages ARE NOT covered by
warranty.
In addition, water leak detection devices and automatic water shuto
valves are readily available at plumbing supply houses. IT IS HIGHLY
RECOMMENDED BY THE MANUFACTURER TO INSTALL WATER LEAK
DETECTION DEVICES AND AUTOMATIC SHUTOFF VALVES IN ANY
APPLIANCE INSTALLATION WHERE A LEAKAGE OF WATER COULD
RESULT IN PROPERTY DAMAGES.

LP-314 Rev. 012 Rel. 003 Date 9.27.19
8
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 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.
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
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.
Figure 1 - Drain Pan Dimensions and Recommended Service Clearances
PLUS 2" MINIMUM
DIAMETER OF WATER HEATER
06/28/10
LP-179-W
TO OPEN DRAIN
LINE SHOULD BE AT
LEAST 3/4" ID AND
PITCHED FOR PROPER
DRAINAGE.
MAXIMUM 2"
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.
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.
NOTE: A combustible door or removable panel is acceptable front
clearance.
D. Residential Garage and Closet Installations
Precautions
If the heater 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.
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.
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.
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.
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.
Failure to vent the appliance properly will result in serious personal
injury or death.
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.

LP-314 Rev. 012 Rel. 003 Date 9.27.19
9
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.
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 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.
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.
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.
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.
F. 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.
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.

LP-314 Rev. 012 Rel. 003 Date 9.27.19
10
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.)
Failure to follow all instructions can result in ue gas spillage and
carbon monoxide emissions, causing severe personal injury or death.
H. Removing an Appliance from a Common Vent System
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.

LP-314 Rev. 012 Rel. 003 Date 9.27.19
11
• Hardness less than 12 grains (200 mg/L) (Residential Use - water temperatures below 140oF)
• Hardness less than 7 grains (120 mg/L) (Commercial Use - water temperatures of 140oF and greater)
• Hardness levels above the required amounts can lead 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.
• 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.
Figure 3 - Appliance Dimensions - NOTE: All Dimensions Are Approximate

LP-314 Rev. 012 Rel. 003 Date 9.27.19
12
Part 4 - Domestic Hot Water and Hydronic 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.
DO NOT pipe the water heating side of this appliance with black iron,
galvanized steel, steel, or lead pipe. Doing so will result in premature
product failure and property damage, and WILL VOID the warranty.
A. 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.
Domestic water connections must be installed in accordance with
all local and national plumbing codes or any applicable prevailing
standards. The appliance is supplied with a rated mixing valve certied
to ASSE 1017. You must completely follow the instructions included
with the mixing valve for proper installation. This mixing valve must be
installed on the domestic outlet to assure that hot water temperature
does not vary more than +/– 5°F, as the unit adjusts its stored water
automatic set point to meet the requirements of the hydronic heating
module. The valve MUST NOT be allowed to freeze. If the mixing valve
is installed in a potentially freezing situation, suitable insulation must
be tted to prevent damage. DO NOT use excess thread sealant (in
liquid, tape or other form) as this may cause the mixing valve to fail.
Toxic chemicals shall not be introduced into the mixing valve system.
NOTE: Recommend to the user that the mixing valve be checked
annually to ensure its continued function.
1. System Domestic Water Piping
The domestic inlet and outlet ports on the appliance are 1” NPT
connections. We recommend the installation of shut-o valves and
unions on both the inlet and outlet ports to isolate the appliance for
future service.
It is important that the connections on the inlet and outlet are brass or
copper. Never use dielectric unions or galvanized steel ttings. Teon
thread sealant must be used to seal all tank connections. An approved
ASSE 1017 mixing valve is provided with every appliance and must be
installed on the outlet to protect the user from scalding temperatures.
This valve reduces the point of discharge temperature by mixing the
hot and cold water from the discharge outlet or mixed outlet port. This
device alone will not protect the user from scalding temperature. To
install and set up the mixing valve, follow the pre-installation steps in
this manual and also follow the enclosed instructions included with
the mixing valve.
2. Appliance Domestic Water Piping
B. 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
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
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.

LP-314 Rev. 012 Rel. 003 Date 9.27.19
13
C. Mixing Valve Installation
1. All installations must be carried out by licensed professionals.
2. The installer must ensure compatibility of all installations.
Example: Temperature of hot water – marked “H”, cold water inlet –
marked “C”, and mixed outlet – marked with directional arrow.
3. The mixing valve may be installed in any position.
4. Local codes shall take priority over any inconsistency in these
instructions.
5. During startup, you must ensure that the valve is set to the
desired temperature (the mixing valve preset is 120oF). If the valve
temperature needs to be adjusted, please refer to the mixing valve
instructions and/or the following settings.
This appliance can deliver scalding temperature water at any
faucet in the system. Be careful whenever using hot water to
avoid scalding injury. By setting the thermostat on this appliance
to obtain increased water temperature, you may create a higher
potential for scald injury. To protect against injury, you should
install the ASSE approved thermostatic mixing valve (a device to
limit the temperature of water to protect against scald injury by
mixing hot and cold water supply) shipped with appliance in the
system. This valve will reduce point of discharge temperature in
branch supply lines. Install this valve according to the directions in
the mixing device packaging. DO NOT OPERATE THIS APPLIANCE
WITHOUT AN ASSE APPROVED THERMOSTATIC MIXING DEVICE.
If this appliance was shipped without an ASSE approved
thermostatic mixing valve, contact the manufacturer. Failure
to install the mixing valve could result in substantial property
damage, severe personal injury, or death.
The mixing valve is certied to ASSE 1017. It is not to be used
to provide anti-scald service resulting from system pressure
uctuations, and should not be used where more sophisticated
compensating temperature controls are required.
Notes:
1Maximum permissible temperature in accordance with ASSE 1070.
The limit locking ring may be adjusted for applications not requiring
ASSE 1070 valves.
2Maximum allowable variation in either supply pressure in order to
control the outlet temperature to within +/- 3oF. Warning: Pressure
variations outside of this range may cause changes in the outlet
temperature.
Mixing Valve Specications
Min. – Max. Hot Water Inlet Temperature 120-180oF (49 - 82oC)
Min. – Max. Cold Water Inlet Temperature 39 - 80oF (4 - 27oC)
Max. Working Pressure 200 PSI
Min. Flow Rate 1 GPM
Outlet Water Temperature Range 85–130oF (29–54oC)
Min. Temperature Dierential
(Between Hot Supply and Outlet) 27oF (15oC)
Factory Set Locking Ring 120oF Max.1
Allowable Supply Pressure Variation +/- 20%2
Accuracy of Outlet Temperature +/-3oF (3.4oC)
Performance –
CV 1.8
Max Flow – 1” 14 gpm
Do not solder unions while attached to the valve body. Solder
connections prior to connecting unions to the valve body to avoid
damaging the valve and its function. Failure to follow this instruction
could result in property damage, serious personal injury, or death.
Setting the Mixing Valve Outlet Temperature
1. Turn both the hot and cold water supplies on. Open an outlet,
preferably a sink or basin faucet rather than a shower. To calibrate, let
water run for 2 minutes and measure the outlet temperature with a
thermometer. Adjust the green cap counter clockwise to increase and
clockwise to decrease temperature, as shown in the following image.
Figure 4 - Adjusting the Mixing Valve
2. Once the desired outlet temperature has been achieved, ret the
green top so that it snaps onto the body of the mixing valve.
NOTE: See the instruction sheet included with the mixing valve to
adjust the maximum temperature of the mixing valve greater than
120oF.
Hotter water increases the risk of scald injury. Scalding may occur
within 5 seconds at a setting of 140oF (60oC). Water temperature
over 125oF can instantly cause severe burns, or death, from scalds.
Children, disabled, and elderly are at the highest risk of being scalded.
See instruction manual before setting temperature at appliance. Feel
water before bathing or showering!
NOTE: At low ow operation, the outlet temperature may vary slightly
more.
Dierential pressure at the valve inlet should be within a 2 to 1 ratio
under normal ow conditions.
Inline ttings, pipe work, layout and sizing must be taken into
consideration. In installations where the valve is supplied with
unbalanced hot cold pressures greater than a 2 to 1 ratio, please call
the HTP Technical Support Department.
Installation of the Mixing Valve
1. Flush all pipe work thoroughly (with water only) before installing the
mixing valve.
2. The mixing valve comes complete with union type connections for
ease of installation and service.
3. The mixing valve must be removed from the pipe work prior to
soldering the end connections. It is recommended to use a spacer
piece while soldering.

LP-314 Rev. 012 Rel. 003 Date 9.27.19
14
Mixing Valve Maintenance and Service
• It is recommended to check the mixing valve annually to
ensure proper system capabilities. More frequent checks are
recommended in adverse water conditions.
• When checking the mixed water supply temperature, use
the same faucet used in the initial installation temperature
adjustment.
• There may be some variation in the water temperature from
the mixing valve due to seasonal temperature variations in the
cold water supply.
If the water supply is of poor quality, the internal components
may jam, requiring an additional lter or strainer to be tted to
the system. Contact a plumbing professional for appropriate
materials and installation.
D. Auxiliary Connections
The auxiliary connections are additional connections for a recirculation
connection, air handlers, plate exchangers, or other devices that supply
hot water. These connections must be installed in accordance with
all local and national codes or any applicable standard that prevails.
Auxiliary connections are 1” on all models. Never use dielectric unions
or galvanized steel ttings. Use only copper or brass ttings. Sealant
must be used on all connections. The top port is the outlet and the
bottom port is the inlet.
Never connect auxiliary connections to any system that uses glycol
or other solutions formulated for hydronic systems. These auxiliary
connections are to be used only in a potable water system. Failure to
follow this warning could result in serious injury or death.
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. Temperature and Pressure Relief Valve for DHW
Install a temperature and pressure relief valve into the marked port
(upper right). We recommend a WATTS 40XL5 valve or equivalent
for 130,000 BTU models or above input. The valve must meet the
ANSI Z21.22B requirements for relief valves for hot water heaters as
per a nationally recognized lab that maintains a periodic inspection
of production of such listed safety device. The pressure rating of the
valve must not exceed the listed working pressure of this appliance,
and must be rated to the proper BTU/hr capacity of the appliance.
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 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.
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.
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.
F. Backow Preventer
Use a backow preventer specically designed for water heater
installations. This valve should be installed on the cold water ll
supply line per local codes.
G. Potable Expansion Tank
A potable hot water expansion tank is required to oset heated water
expansion. In most city plumbing systems, the water meter has a
no return or back ow device built into the system to prevent back
owing of water into city mains. Some local codes require back ow
preventers on all incoming water supplies. The hot water expansion
tank must be listed for potable water use. The expansion tank should
be located on the cold inlet piping close to the appliance.
Expansion Tank and Make-Up Water
1. Ensure that the expansion tank is sized to correctly handle
appliance and system water volume and temperature.
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.
The expansion tank must be suitable for hot potable water
systems.
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.
Failure to follow the instructions in this section WILL VOID the
warranty and may result in property damage, serious personal
injury, or death.

LP-314 Rev. 012 Rel. 003 Date 9.27.19
15
H. Hydronic Heating Module Piping
The hydronic heating module comes pre-plumbed and connected
directly to the storage tank. The heated water inside the tank will
be circulated through one side of the brazed plate heat exchanger
while the heating system water ows through the other side. The
heating system piping is connected to the return and supply pipes
located on the top of the hydronic heating module (see Figure 5).
Piping of the module to the system is not complex and does not
require any of the primary or secondary piping normally used on
high eciency low mass boilers.
NOTE: Do not connect hydronic heating module to air handler units.
This module may not be applied to air handler applications.
I. Pressure Relief Valve for the Hydronic System
The pressure relief valve supplied with the appliance is designed to
relieve pressure greater than 30 psi. The hydronic heating module is
designed to withstand pressure up to 150 psi. If you are changing the
pressure relief valve for a higher pressure rating, you must make sure
that the system components are designed for the higher pressure.
The relief valve must be rated for the 135,000 Btu maximum capacity
of the brazed plate heat exchanger. Pipe the discharge line in copper
piping to a drain. Provide 6” clearance from the oor drain.
J. Hydronic Expansion Tank and Make-Up Water
Ensure that the expansion tank is sized to the system volume, brazed
plate capacity, and related piping for the hydronic heating module.
The capacity of the module and brazed plate is ½ gallon. Most
chilled water systems are piped using a closed type expansion tank.
Connect the expansion tank to the air separator only if the separator
is on the suction side of the circulator. The hydronic heating module
has a water line connection of ½” NPT to connect into the pressure
reducing valve and back ow preventer. Normal system pressure is
15 psi.
K. Hydronic Heating Module System Piping
The hydronic heating module is designed to function in a closed loop
hydronic system. The included temperature and pressure gauge
allows the user to monitor the system pressure and temperature
from the hydronic heating module.The gauge should be installed on
the supply outlet piping from the heating module. The installation
of an air elimination device will remove air from the system which
is necessary to avoid an air lock in the central heating circulator. It
is recommended that all the piping is insulated to improve on the
system’s overall eciency. In the system piping, heating coils in air
handler, ow control valves, or other devices must be installed to
prevent gravity circulation of heated water from the heating module.
Freeze protection for new or existing systems must be composed
of glycol that is specically formulated to include inhibitors that will
prevent the glycol from attacking the metallic system components.
Make certain that the system uid is checked for the correct glycol
concentration and inhibitor level. The system should be tested at
least once a year or as recommended by the producer of the glycol
solution. Allowance should be made for the expansion of the glycol
solution in the system piping. Example: 50% by volume glycol
solution expands 4.8% in volume for the temperature increase from
32oF to 180oF, while water expands 3% with the same temperature
rise.
Listed below are the basic steps that will help guide you through the
installation of the hydronic heating module to the system piping.
1. Connect the system return marked“Return”.
2. Connect the system supply marked “Supply”.
3. Install a balance and purge valve (or shut o drain valve) on the
system return to purge air out of the zone at start-up.
4. Install a back ow preventer on the cold feed make–up water line.
5. Install a pressure reducing valve on the cold feed make up water
line (15 psi operating pressure). Check temperature and pressure
gauge when operating. It should read minimum pressure of 15 psi.
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.
6. Install the system circulator as shown in the piping details in 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 the
expansion tank manufacturer’s instructions for specic information
related to expansion for the required system volume and capacity.
8. Install an air elimination device on the system supply.
9. Install a drain valve at the lowest point of system to blow out the
system if needed. NOTE: The hydronic heating module cannot be
drained completely of water without purging the unit with an air
pressure greater than 15 psi but not exceeding 40 psi. If winterizing
the unit it is recommended, use glycol on the closed loop hydronic
side only.
10. The relief valve is installed at the factory. A pipe discharge line
should be installed to release 6” above a drain, so discharge will be
visible when pressure is relieved. The pipe size must be the same size
as the relief valve outlet.
Figure 5 - Hydronic Heating Module
L. Hydronic Heating Module Output
Hydronic heating module output is based on the burner input and the
ow rate supplied by the selected system circulator through the closed
loop side of the brazed plate exchanger. Included in this section are
graphs that will help you size the appropriate circulator and output
needed to meet your system design requirements. Below is an example
on the steps needed to determine the correct circulator for the system.
Example: System design requires 120,000 Btu at 20 Delta
Step 1
Using the graphs, select the input rate of the appliance. In this example,
we would have to select a minimum input of 199K (the 130K max.
output is 100,000 Btu, which falls below our operating point).
Step 2
Next, go to the chart for the 199K burner input and select the point of
operation where the Btu and Delta T line intersect. Mark the point on
the chart and go to bottom of the chart to determine ow rate needed
to achieve the rated output from the module. This example is 12 GPM.

LP-314 Rev. 012 Rel. 003 Date 9.27.19
16
Figure 6 - Sizing Chart for 130kBTU Model
Figure 7 - Sizing Chart for 199kBTU Model
Step 3
Select the correct circulator to meet the ow and resistance requirements for the system design. To calculate this, you must determine the
ow and resistance through the system and heating module. The heating module requires 12 GPM at 10 feet of head. The system requires
12 GPM at 5 feet of head. To select a circulator, add the resistance 10 feet of head (module) + 5 feet of head (system) at 12 GPM. This system
requires a circulator that operates at a resistance of 15 feet at 12 GPM (See examples in Figures 6, 7, and 8).

LP-314 Rev. 012 Rel. 003 Date 9.27.19
17
EXAMPLE: At 12 GPM there is approximately 10 ft of head loss.
Figure 8 - Pressure Drop

LP-314 Rev. 012 Rel. 003 Date 9.27.19
18
M. Applications
Figure 9 - Piping with Air Handler Application
NOTES:
1. Minimum pipe size
should match connection
size on appliance. Upsize
pipe accordingly if greater
ow is required.
2. A thermal expansion tank
suitable for potable water
must be sized and installed
within the piping system
between the check valve
and cold water inlet of the
appliance.
3. Gas line must be rated
to the maximum capacity
of the unit. Unit must have
10 feet of pipe after gas
regulator.
4. All circulators shall have
an integral ow check.
NOTES FOR AIR HANDLER
APPLICATION (APPLIES
TO DOMESTIC WATER
OUTLET CONNECTIONS
ONLY):
1. MASSACHUSETTS STATE
PLUMBING CODE REQUIRES
A DISTANCE NO GREATER
THAN 50 FEET FROM THE
APPLIANCE TO THE FAN
COIL IN THE AIR HANDLER.
2. MASSACHUSETTS STATE
PLUMBING CODE REQUIRES
AN ELECTRONICALLY
TIMED CIRCULATOR PUMP
TO ACTIVATE EVERY SIX
HOURS FOR 60 SECONDS.
THIS CIRCULATOR IS
REQUIRED TO BE BRONZE
OR STAINLESS.
3. ALL WATER PIPING MUST
BE INSULATED.
4. YOU MUST INSTALL A
VACUUM RELIEF VALVE PER
248 CMR.
NOTE: THIS DRAWING IS
MEANT TO DEMONSTRATE
SYSTEM PIPING CONCEPT
ONLY. THE INSTALLER
IS RESPONSIBLE FOR
ALL EQUIPMENT AND
DETAILING REQUIRED BY
LOCAL CODES.
The piping will not support the weight of the appliance circulator pump. Refer to the pump manufacturer’s installation instructions to
properly support the circulator pump. Failure to comply with these instructions could result in substantial property damage, severe personal
injury, or death.
DO NOT use the heat pack for high temperature (over 160oF) applications. Failure to comply will result in substantial overworking of the
appliance, and possibly lead to early appliance failure. Use of the heat pack for high temperature applications WILL VOID the warranty.
Figure 10 - Piping with Zone Valves
CAUTION

LP-314 Rev. 012 Rel. 003 Date 9.27.19
19
Figure 11 - Piping with Zone Circulators
NOTES:
1. Minimum pipe size should
match connection size
on appliance. Upsize pipe
accordingly if greater ow is
required.
2. A thermal expansion tank
suitable for potable water
must be sized and installed
within the piping system
between the check valve
and cold water inlet of the
appliance.
3. Gas line must be rated to
the maximum capacity of the
unit. Unit must have 10 feet
of pipe after gas regulator.
4. All circulators shall have an
integral ow check.
NOTES FOR AIR HANDLER
APPLICATION (APPLIES TO
DOMESTIC WATER OUTLET
CONNECTIONS ONLY):
1. MASSACHUSETTS STATE
PLUMBING CODE REQUIRES
A DISTANCE NO GREATER
THAN 50 FEET FROM THE
APPLIANCE TO THE FAN COIL
IN THE AIR HANDLER.
2. MASSACHUSETTS STATE
PLUMBING CODE REQUIRES
AN ELECTRONICALLY TIMED
CIRCULATOR PUMP TO
ACTIVATE EVERY SIX HOURS
FOR 60 SECONDS. THIS
CIRCULATOR IS REQUIRED TO
BE BRONZE OR STAINLESS.
3. ALL WATER PIPING MUST
BE INSULATED.
4. YOU MUST INSTALL A
VACUUM RELIEF VALVE PER
248 CMR.
NOTE: THIS DRAWING IS
MEANT TO DEMONSTRATE
SYSTEM PIPING CONCEPT
ONLY. THE INSTALLER
IS RESPONSIBLE FOR
ALL EQUIPMENT AND
DETAILING REQUIRED BY
LOCAL CODES.
The piping will not support the weight of the appliance circulator pump. Refer to the pump manufacturer’s installation instructions to
properly support the circulator pump. Failure to comply with these instructions could result in substantial property damage, severe personal
injury, or death.
DO NOT use the heat pack for high temperature (over 160oF) applications. Failure to comply will result in substantial overworking of the
appliance, and possibly lead to early appliance failure. Use of the heat pack for high temperature applications WILL VOID the warranty.
Figure 12 - Piping with Recirculation
CAUTION

LP-314 Rev. 012 Rel. 003 Date 9.27.19
20
• Make certain the drain valve is completely closed.
• Open the shut-o valve in the cold water supply line.
• Open the hot water faucets to allow air to vent from the
appliance and piping.
• Allow sucient time for the appliance to completely ll with
water.
N. Filling the Appliance
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.
Part 5 - Venting
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: Care must be taken to prevent condensate freezing in the
exhaust vent pipe system. See local, state, provincial, and national
codes for best practices to prevent condensate freezing in the exhaust
vent pipe system.
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.
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.
• DO NOT insulate the rst three (3) linear feet of the exhaust
vent run.
• CPVC, Polypropylene, or Stainless
Steel pipe material MUST be used
if the rst three (3) linear feet of
the exhaust vent run is insulated or
passes through an enclosed space
greater than 6” in length, such as
a wall. NOTE: Only Stainless Steel
pipe material may be insulated.
• If CPVC is used to meet these
requirements, the balance may be
installed with approved PVC pipe.
• If Polypropylene or Stainless Steel is used to meet these
requirements, the balance of the vent run must be installed
with the same material.
• Failure to comply with this warning could result in property
damage, severe personal injury, or death.
Exhaust
LP-179-JJ
11/30/17
Length
Greater than
Six (6) Inches
Enclosed
Space
Within First Three (3) Linear Feet of
Appliance Exhaust Vent Adapter