HTP Elite Ultra ELU-150WBN Installation manual

Elite UltraTM
High Eciency Condensing
Wall-Hung Gas Boilers
Installation
Start-Up
Maintenance
ELU-150WBN / ELU-199WBN / ELU-199WCN Models
DANGER
!
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.
NOTICE
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
420011303900 Revision Date 2.28.22
WARNING
!
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.
Heat Exchanger Bears the ASME “H” Stamp

420011303900 - Revision Date 2.28.22
2
WARNING
!
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 qualified installer, service agency, or gas supplier.

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3
SPECIAL ATTENTION BOXES
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
WARNING indicates a potentially hazardous situation which, if not
avoided, could result in personal injury or death.
!
CAUTION
CAUTION indicates a potentially hazardous situation which, if not
avoided, may result in moderate or minor personal injury.
CAUTION
CAUTION used without the safety alert symbol indicates a
potentially hazardous situation which, if not avoided, may result in
property damage.
NOTICE
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 boiler. 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 in the United States and the Natural Gas and Propane
Installation Code - B149.1 in Canada (latest versions), be reviewed in
their entirety before beginning any work.
For the Installer
This boiler must be installed by qualied and licensed personnel. The
installer should be guided by the instructions furnished with the boiler,
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 in the United States and the Natural Gas and Propane
Installation Code - B149.1 in Canada (latest versions).
Installations Must Comply With:
Local, state, provincial, and national codes, laws, regulations, and
ordinances.
In the United States - 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.
The latest version of the National Electrical Code, NFPA No. 70.
In Canada - The latest versions of the Natural Gas and Propane
Installation Code, CSA B149.1, and the Canadian Electrical Code, C22.1,
from CSA Group, 178 Rexdale Blvd, Toronto, Ontario, Canada M9W 1R3.
NOTE: The gas manifold and controls met safe lighting and other
performance criteria when undergoing tests specied in ANSI Z21.13
- latest edition.
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,
provincial, 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.
DANGER
!

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4
PART 1 - GENERAL SAFETY INFORMATION 6
A. Operation and Installation Warnings 6
B. Improper Combustion 7
C. Gas 7
D. When Servicing the Boiler 7
E. Boiler System 7
F. CH and DHW Loop Water Chemistry Requirements 7
G. Freeze Protection 8
H. Water Temperature Adjustment and Scalding 9
I. High Elevation Installations 9
PART 2 - BEFORE YOU START 10
A. What’s in the Box 10
B. Optional Equipment 11
PART 3 - PREPARE THE BOILER FOR INSTALLATION 11
A. Locating the Boiler 11
B. Leveling 12
C. Clearances for Service Access 12
D. Wall Mounting Considerations 13
E. Wall Mounting Instructions 13
1. Mounting to a Concrete Wall 13
2. Mounting to a Wood Studded Wall 13
F. Residential Garage and Closet Installations 13
G. Exhaust Vent and Intake Pipe 14
1. Direct Vent of Exhaust and Intake 14
2. Power Venting, Indoor Combustion Air in Conned or
Unconned Space 14
H. Carbon Monoxide Detectors 15
I. Prevent Combustion Air Contamination 16
J. Removing a Boiler from a Common Vent System 16
K. Technical Specications 17
PART 4 - WATER PIPING 21
A. General Plumbing Information 21
B. Backow Preventer 21
C. Expansion Tank 21
D. Piping the Boiler 22
E. Internal Circulation Pump 23
F. CH and DHW Pressure Relief Valves 23
G. Air Elimination Device 24
H. Low Water Cut-O (Field Supplied) 24
I. Applications* 24
J. Floor Drying Function 32
NOTICE
NOTICE
The hydronic supply and return connections of these products
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,
severe 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.
IMPORTANT
In accordance with Section 325 (f) (3) of the Energy Policy and
Conservation Act, HTP has provided this boiler with multiple
features designed to save energy by reducing the boiler water
temperature as heating load decreases.
These features include:
• A modulating combustion system that adjusts firing rate
based on heat demand.
• Adjustment of boiler set point based on inferred heat load
as determined by an outdoor sensor. The outdoor sensor is
supplied with this boiler.
• This boiler does not include a standing pilot.
• This boiler is designed and shipped to assure the highest
efficiency operation possible. Such high efficiency is
achieved by limiting heating circuit water temperature to
140°F when there is no anticipated heat load, based upon
the outdoor sensor and the Outdoor Reset Slope (sensor
response slope) in the boiler software.
• This feature may be over-ridden as described below in
specific installations:
• The boiler control is equipped with an outdoor sensor
override for use with building management systems or in
cascaded systems (for systems with total input of 300,000
BTU/hr or greater).
See statement below for an important notice on the use of the
override.
IMPORTANT
In accordance with Section 325 (f) (3) of the Energy Policy
and Conservation Act, this boiler is equipped with a feature
that saves energy by reducing the boiler water temperature
as the heating load decreases. This feature is equipped with
an override which is provided primarily to permit the use of
an external energy management system that serves the same
function. THIS OVERRIDE MUST NOT BE USED UNLESS AT
LEAST ONE OF THE FOLLOWING CONDITIONS IS TRUE:
• An external energy management system is installed that
reduces the boiler water temperature as the heating load
decreases.
• This boiler is not used for space heating.
• This boiler is part of a modular or multiple boiler system
having a total input of 300,000 BTU/hr or greater.
ASME CSD-1, Section CW-400 requires the temperature controls of
hot water heating boilers to
a) be accepted by a nationally recognized testing agency to
conform to UL 353,
b) shuto the fuel supply when the system water reaches a preset
operating temperature,
c) have a high temperature limit control that prevents the
water temperature from exceeding the maximum allowable
temperature by causing safety shutdown and lockout.
The temperature controls of this boiler have been accepted by a
nationally recognized testing agency to conform to UL 353; they
work to shuto the fuel supply when the system water temperature
reaches the preset operating temperature; and they cause a safety
shutdown and lockout, requiring a manual reset to start, when the
water temperature reaches 212°F.
TABLE OF CONTENTS
!
WARNING

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5
PART 13 - TROUBLESHOOTING 76
A. Boiler Protection Devices 76
1. Blocking Error 76
2. Lockout Error 76
3. Malfunction Warning 76
B. Boiler Error Codes 77
PART 14 - MAINTENANCE 89
A. Procedures 89
B. Maintenance That May be Performed by the User 89
C. Maintenance Only to be Performed by a Qualied
Service Technician 90
D. Replacing Components 93
E. After Maintenance is Complete 95
PART 15 - MAINTENANCE REPORT 96
PART 16 - SHUTDOWN 98
A. Shutdown Procedure 98
B. Failure to Operate 98
C. Important 98
Maintenance Notes 99
Customer Installation Record Form 102
PART 5 - VENTING 33
A. General 33
B. Approved Materials for Exhaust Vent and Intake Pipe 34
C. Additional Requirements for Installation in Canada 34
D. Exhaust Vent and Intake Pipe Location 35
E. Exhaust Vent and Intake Pipe Sizing 36
F. Tightening Boiler Collar to Exhaust Vent and Intake Pipe 36
G. Exhaust Vent and Intake Pipe Installation 37
H. Applications 38
1. Direct Vent Installation of Exhaust and Intake 38
2. Venting Through an Existing System 44
3. Power Venting, Indoor Combustion Air in Conned
or Unconned Space 45
PART 6 - INSTALLING THE CONDENSATE DRAIN 46
PART 7 - CONNECTING ELECTRICAL SERVICE 47
A. Wiring 47
1. Connecting Power (120V) for DHW and CH Circulators 47
2. Low Voltage Wiring Connections 47
3. Room Thermostat Wiring Connections 48
4. Outdoor Sensor Connections 48
5. Aquastat (Default) and Tank Sensor (Optional)
Connections (non Combi Models) 48
B. Internal Wiring Details 49
PART 8 - GAS CONNECTIONS 53
A. Gas Pipe Sizing Tables 53
1. Gas Pipe Sizing 53
2. Natural Gas Pipe Sizing 53
3. LP (Liquid Propane) Gas Pipe Sizing 53
B. Gas Connection Requirements 53
C. Additional Precaution for Excess Flow Valve (EFV) 54
D. Checking Gas Pressure at the Boiler for Proper Operation 54
PART 9 - CONTROLS 55
A. Control and Display Overview 55
B. Ignition Procedure 56
C. Central Heating (CH) Temperature Adjustment 56
D. Domestic Hot Water (DHW) Temperature Adjustment 56
E. Automatic CH Temperature Control (AUTO) 57
F. Type of Temperature Control 58
G. Slope of Outdoor Reset Curve 58
H. Parallel Shift of Reset Curve 59
I. Auto Boost 59
J. Technical Menu - Access and Navigation 60
K. Technical Menu - Menu Structure 61
L. Technical Menu - Complete Menu 62
PART 10 - START-UP PREPARATION 70
A. Check / Control Water Chemistry 70
B. Check for Gas Leaks 70
C. Freeze Protection (When Used) 70
D. System Water Fill, Purge, and Test 71
E. Purge Air from DHW System 71
F. Check Thermostat Circuit(s) 71
G. Condensate Removal 71
PART 11 - START-UP 72
A. First Ignition 72
B. Combustion Checking Procedure 72
C. Checking Combustion Parameters 74
D. Converting the Appliance from Natural Gas to
Propane Operation 74
PART 12 - INSTALLATION CHECKLIST 75

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6
NOTE: If the boiler is exposed to re or water (or is any way damaged),
do not operate. Immediately call a qualied service technician. Failure
to follow this information could result in property damage, severe
personal injury, or death.
This boiler must be installed by a qualied service technician. Improper
installation and/or operation can cause a potentially hazardous
situation, which if not avoided will void the warranty and could result
in serious injury or death.
The manufacturer cannot anticipate every circumstance that might
involve a potential hazard. Each installation has its own specialized
characteristics, requirements, and possible hazards. Therefore, all
possible incidents are not included in these warnings. Proper and
safe installation, operation, and service are the responsibility of the
qualied service technician.
Proper care of the boiler is the user’s responsibility. Ensure the user
carefully reads and understands the User’s Information Manual before
operating the boiler.
Make sure the user knows the location of the gas shut-o valve and
how to operate it. Immediately close the gas shut-o valve if the
appliance is subjected to re, overheating, ood, physical damage,
or any other damaging condition that might aect the operation of
the unit. Have the appliance checked by a qualied service technician
before resuming operation.
Make sure the user knows the location of the gas shut-o valve and
how to operate it. Immediately close the gas shut-o valve if the
appliance is subjected to re, overheating, ood, physical damage,
or any other damaging condition that might aect the operation of
the unit. Have the appliance checked by a qualied service technician
before resuming operation.
Do not power up the unit unless the gas and water supply valves are
fully opened. Make sure the fresh air intake port and exhaust gas port
are open and functional.
No one but a qualied service technician should attempt to install,
service, or repair this boiler. There are no serviceable parts which can
be changed by the user / owner.
User / Owner: Contact the original qualied service technician if
the boiler needs repair / maintenance. If the original technician is
unavailable, ask your gas supplier for a list of qualied service providers.
DO NOT store or place newspapers, laundry, or other combustible
items near the appliance or the exterior exhaust gas outlet and/or fresh
air inlet port.
The owner should inspect the system monthly for damage, water
stains, signs of rust, corrosion, and exhaust vent and air intake
blockage. If inspection of the unit shows signs of damage, the
boiler should be shut o until the problem is repaired by a qualied
technician.
After installation, all appliance safety devices should be tested.
The boiler is certied for indoor installations only. The boiler consists
of gas ignition system components which must be protected from
water (dripping, spraying, etc.) during operation and service. Carefully
consider installation location and the placement of critical components
(circulators, condensate neutralizers, etc.) before installing the boiler.
DO NOT allow children to operate this boiler. DO NOT use this boiler
if it does not appear to be operating correctly. A qualied service
technician should service and inspect the boiler annually.
PART 1 - GENERAL SAFETY INFORMATION
This boiler 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. Boiler must have room for service: 18” front,
14” top, 12” bottom, 2” left and right sides and 0” back are minimum
recommended service clearances. (A combustible door or removable
panel is acceptable front clearance. A 3” minimum clearance must
be provided from the boiler front cover to the removable panel or
combustible door.) This boiler has been approved for closet installation
and installation on combustible ooring. Do not install directly on
carpeting. Install the boiler in a location where 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.
This appliance is rated Category IV (pressurized vent, likely to form
condensate in the vent) and requires a special vent system designed
for pressurized venting. 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 service technician.
Have this boiler 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 boiler.
NOTE: Install all system components and piping in such a manner
that does not reduce the performance of any re rated assembly.
A. Operation and Installation Warnings
To avoid serious injury or death, read, understand, and follow all of the
precautions listed here.
Vapors from ammable liquids will explode and cause a re,
resulting in personal injury or death. The boiler has a burner that
can come on at any time and ignite vapors. DO NOT use or store
ammable liquids around the boiler.
Improper venting can cause a build-up of carbon monoxide.
Breathing carbon monoxide can result in brain damage or death.
DO NOT operate the boiler unless it is properly vented to the
outside and has an adequate fresh air supply for safe operation.
Inspect the exterior exhaust gas outlet port and fresh air inlet port
on a regular basis to ensure they are functioning properly.
A concentration of carbon monoxide as small as .04% (400 parts
per million) in the air can be fatal. When making high re or low
re adjustments, CO levels must be monitored using a calibrated
combustion analyzer such that a CO level of no more than 150 ppm
is exceeded at any time during operation.
Adjusting the “low re oset” or the “main ow restrictor” in small
increments can result in a signicant increase in CO concentration.
To avoid serious injury or death, DO NOT make any adjustments
to the gas valve without monitoring the exhaust gases with a fully
functional and calibrated combustion analyzer.
Failure to follow these instructions will result in property damage,
severe personal injury, or death.
!
WARNING
!
WARNING
DANGER
!
PART 1

420011303900 - Revision Date 2.28.22
7
DO NOT USE THIS BOILER IF ANY PART HAS BEEN SUBMERGED
IN WATER. Immediately call a qualied service technician. The
boiler MUST BE replaced if it has been submerged. Attempting to
operate a boiler 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 boiler
could result in property damage, severe personal injury, or death.
NOTE: Boiler damage due to ood or submersion is considered an
Act of God, and IS NOT covered under product warranty.
DO NOT alter or modify the appliance or appliance controls.
Altering any HTP boiler with parts not manufactured by HTP WILL
INSTANTLY VOID the boiler warranty and could result in property
damage, personal injury, or death.
This appliance is equipped with a three prong plug. It should
only be plugged directly into a properly grounded three prong
receptacle. DO NOT remove the ground plug from the plug.
This appliance provides an overheat shutdown limit. In the event
the appliance water temperature exceeds the setpoint of the control
limit, the cuto will trip and the appliance will shut down. Certain
local codes require additional temperature limits. In addition,
certain types of systems may operate at temperatures below the
minimum setpoint of the limit provided with the appliance. Contact
the manufacturer for additional overheat controls.
B. 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.
C. Gas
Should overheating occur or gas supply fail to shut o, turn o the
manual gas control valve to the boiler.
D. When Servicing the Boiler
• To avoid electric shock, disconnect electrical supply before
performing maintenance.
• To avoid severe burns, allow boiler and associated equipment to
cool before servicing.
• Do not use petroleum-based cleaning or sealing compounds in
boiler system. Gaskets and seals in the system may be damaged,
possibly resulting in substantial property damage.
• Do not use “homemade cures” or “boiler patent medicines”.
Substantial property damage, damage to boiler, and/or serious
personal injury may result.
• Always verify proper operation after servicing the boiler.
NOTE: When inquiring about service or troubleshooting, reference the
model and serial numbers from the boiler rating label.
Be sure to disconnect electrical power before opening boiler
cabinet or performing service. Label all wires while performing
service to ensure proper re-wiring of the appliance. Wiring errors
can cause improper or dangerous operation. Failure to do so could
result in electrical shock, improper boiler or system operation,
property damage, serious personal injury, or death.
Do not use this boiler for anything other than its intended purpose
(as described in this manual). Doing so could result in property
damage and WILL VOID product warranty.
Due to the low water content of the boiler, improper sizing of the
boiler with regard to heating system load will result in excessive
cycling and accelerated component failure. DO NOT under or
oversize the boiler to the system. Modular boiler installations
greatly reduce the likelihood of boiler oversizing. HTP DOES NOT
warrant failures caused by improperly sized boiler applications.
High heat sources (sources generating heat 100oF / 37oC or
greater, such as stove pipes, space heaters, etc.) may damage plastic
components of the boiler 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 boiler and related components near high heat
sources.
E. Boiler System
• Thoroughly ush the system (without the boiler connected)
to remove sediment. The high-eciency heat exchanger can
be damaged by build-up or corrosion due to sediment. The
manufacturer recommends a suction strainer in this type of
system.
• Do not use petroleum-based cleaning or sealing compounds in
boiler system. Gaskets and seals in the system may be damaged,
possibly resulting in substantial property damage.
• Do not use “homemade cures” or “boiler patent medicines”.
Substantial property damage, damage to the boiler, and/or
serious personal injury may result.
• Continual fresh make-up water will reduce boiler life. Mineral
buildup in the heat exchanger reduces heat transfer, overheats
the stainless steel heat exchanger, and causes failure. Addition
of oxygen from make-up water can cause internal corrosion
in system components. Leaks in the boiler or piping must be
repaired at once.
NOTE: DO NOT add cold make up water to the system when the
boiler is hot. Thermal shock can potentially cause cracks in the heat
exchanger. Such damage IS NOT covered by warranty.
F. CH and DHW Loop Water Chemistry Requirements
Chemical imbalance of the water supply may aect eciency and
cause severe damage to the boiler 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 boiler service life. Failure of a boiler due to lime scale build-
up, low pH, or other chemical imbalance IS NOT covered by the
warranty.
!
WARNING
!
WARNING
!
WARNING
CAUTION
NOTICE
CAUTION
PART 1

420011303900 - Revision Date 2.28.22
8
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. See Table 1.
If you suspect that your water is contaminated in any way, discontinue
use of the appliance and contact an authorized technician or licensed
professional.
CH Loop Total Water Hardness Specifications
Contaminant Maximum Allowable Level
Total Hardness 120 mg/l
(7 grains/gallon)
DHW Loop Total Water Hardness Specifications
Contaminant Maximum Allowable Level
Total Hardness
(Below 140oF water temperature)
200 mg/l
(12 grains/gallon)
Total Hardness
(Above 140oF water temperature)
120 mg/l
(7 grains/gallon)
CH and DHW Loop Water Quality Specifications
Contaminant Maximum Allowable Level
Aluminum 0.05 to 0.2 mg/l or PPM
Chloride 100 mg/l or PPM
Copper 1 mg/l or PPM
Iron 0.3 mg/l or PPM
Manganese 0.05 mg/l or PPM
pH 6.5 - 8.5
Sulfate 205 mg/l or PPM
Total Dissolved Solids (TDS) 500 mg/l or PPM
Zinc 5 mg/l or PPM
Dissolved Carbon Dioxide (CO2) 15 mg/l or PPM
Table 2 - Water Quality Specifications
G. Freeze Protection
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.
Consider piping and installation when determining boiler location.
Damages resulting from incorrect installation or from use of
products not approved by the manufacturer ARE NOT covered by
warranty. Failure of the boiler due to freeze related damage IS NOT
covered by product warranty.
NOTE: Loops Serving Indirect Water Heaters (IWHs)
Glycol used in IWH loops should be food grade propylene glycol,
FDA rated as “generally recognized as safe” (GRAS). If using a glycol /
potable water mix, the water chemistry must meet the requirements
in this manual. The glycol content of the liquid must not exceed 50%,
On ELU-150WBN / ELU-199WBN Models ONLY
If the boiler is to be used only in Heating Mode (not connected
to an indirect water heater), the electrical connection of the
3-way valve motor MUST BE DISCONNECTED while the boiler
is operating in central heating mode. This will lock the valve
motor in central heating mode and ensure freeze protection
operates properly. Failure to disconnect the valve may disable
boiler freeze protection and result in property damage.
Table 1 - Freeze Protection Detail
FREEZE PROTECTION OPERATION
STAGE 1
Condition The water temperature detected by probes NTC1 or
NTC2 ranges between 39oF (4oC) and 46oF (8oC).
Events
• The internal pump operates at high speed.
• The 3-Way Valve alternately switches positions - 1
minute on heating mode to 1 minute on DHW
mode
• The display shows the icon.
Time Until the NTC1 and NTC2 temperature is greater than or
equal to 46°F (8°C)
If after 20 minutes the conditions described in Stage 1
are still present, the boiler proceeds to Stage 2.
STAGE 2
Condition The water temperature detected by probes NTC1 or
NTC2 is less than 39oF (4oC).
Events
• The burner turns on at minimum power.
• The 3-Way Valve is positioned on DHW and
switches every 30 seconds between CH and DHW.
• When the temperature is greater than or equal to
104oF (40oC) the burner will turn o. The boiler will
maintain the temperature between 95oF (35oC) and
104oF (40oC) for 45 minutes.
• After 45 minutes there will be 2 minutes of post
heating circulation.
• If the temperature falls below 46oF (8oC) within
150 minutes the burner will immediately power on
again.
• The display shows the icon.
Time Until the NTC1 temperature is greater than or equal to
104oF (40oC)
unless the manufacturer species a dierent ratio. Glycol should be
checked periodically to prevent it from becoming acidic. Please refer
to guidelines provided by the glycol manufacturer regarding glycol
maintenance.
NOTE: Glycol not recognized as GRAS may only be used in closed loop
CH applications.
NOTE: HTP DOES NOT WARRANT THE BOILER AGAINST FREEZE-
RELATED DAMAGE.
The boiler control is equipped with freeze protection that activates
based on internal water temperature. See the following table for
details on freeze protection operation.
NOTE: Freeze protection will not be active if the boiler loses power.
CAUTION
CAUTION
!
WARNING
PART 1

420011303900 - Revision Date 2.28.22
9
H. Water Temperature Adjustment and Scalding
This boiler 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 boiler to obtain the
increased water temperature
required by these appliances
you may create the potential
for scald injury.
To protect against injury,
install a mixing valve in the
water system. This valve will
reduce point of use discharge
temperatures by mixing cold
and hot water in branch supply
lines. Such valves are available
from your local plumbing
supplier.
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.
The use of glycol may reduce the usable BTU output of the boiler,
requiring the unit to be “down-red” by limiting the maximum
operating capacity and/or water temperature. For applications
requiring glycol concentrations greater than 30%, such as snow
melt systems, it is recommended to use a brazed plate heat
exchanger to separate the glycol mixture from the boiler water. See
the following detail drawing.
Figure 1 - Snow Melt Application
I. High Elevation Installations
Combustion - At elevations above 2000 ft, the combustion of the
boiler must be checked with a calibrated combustion analyzer to
ensuresafeand reliable operation.Itisthe Installer’s responsibility
to check and adjust the combustion in accordance with this
manual. Failure to follow these instructions may result in property
damage, serious personal injury, or death.
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 - Time and Temperature Relationship in Scalds
This boiler is designed to operate at its maximum listed capacity in
installations located at 0 - 2000 ft above Sea Level. Since the density
of air decreases as elevation increases, maximum specied capacity
should be de-rated for elevations above 2000 ft (610 m) in accordance
with the table below.
Elevations 2001 ft
(610 m)
3000 ft
(914 m)
4000 ft
(1219 m)
4500 ft
(1372 m)
5000 ft
(1524 m)
In Canada1,
de-rate by: 10% 10% 10% 10% may vary
In USA2,
de-rate by: - 12% 16% 18% 20%
NOTES:
1Canada: Elevations between 2000 - 4500 ft (610 - 1372 m), de-rate by 10%.
Consult local authorities for de-rating for elevations above 4500 ft (1372 m).
2USA: If elevation is above 2000 ft (610 m), de-rate capacity by 4% for every
1000 ft (305 m).
Table 4 - De-Rate % for High Elevations
NOTICE
!
WARNING
PART 1

420011303900 - Revision Date 2.28.22
10
A. What’s in the Box
PART 2 - BEFORE YOU START
Remove the boiler and accessory box from the packaging. Take care to
place the boiler and accessories in a safe location prior to installation
to prevent damage to the mechanical connections.
Figure 2 - Included with the Boiler
Included components:
Table 5 - Included with the Boiler
How the Boiler Operates
ELU condensing technology intelligently delivers hydronic heating
while maximizing eciency. Outlined below are system features and
operation:
Stainless Steel Heat Exchanger
The highly ecient stainless steel heat exchanger is designed to
extract all available heat from the supply line before it is exhausted.
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.
Control
The integrated control system monitors the system and regulates fan
speed to control boiler output. This allows the boiler to deliver only the
amount of heat energy required and nothing more.
The control can be set to monitor outdoor temperature through
an outdoor sensor or through internet weather (with optional WiFi
connection), use an optional room sensor, or use both outdoor
temperature and an optional room sensor to regulate boiler set point.
The system can be further enhanced by installing an indirect water
heater to provide domestic hot water.
The control can regulate the output of multiple boilers through its
cascade system function. The cascade system is capable of connecting
up to eight boilers together in such a way that they function as one
boiler system. This allows for greater turn down ratios and provides
systematic control of the multiple boilers in an installation to minimize
downtime and maximize eciency.
The cascade system works by establishing one boiler as the master and
the other connected boilers as followers. The master boiler requires
a sensor to provide feedback on set point temperature in order to
adjust heating input from the connected boilers. Each cascaded boiler
will have its own pump to provide maximum ow and control heat
exchanger ow rate.
Text Display and Operational Display Icons
The display allows the user to change system parameters and monitor
system outputs.
Gas Valve
Senses suction from the blower, allowing gas to ow only if powered
and combustion air is owing.
Integrated Venturi
Controls air and gas ow into the burner.
Burner
The high grade stainless steel burner uses premixed air and gas to
provide a wide range of ring rates.
Spark Ignition
The burner is ignited by applying high voltage through the system
spark electrode. The spark from the electrode ignites mixed gas o of
the burner.
Supply Water Temperature Sensor
This sensor monitors the boiler outlet water temperature (System
Supply). The control adjusts boiler ring rate so the supply temperature
will match the boiler set point.
Return Water Temperature Sensor
This sensor monitors boiler return water temperature (System Return).
Flue Sensor
Monitors ue temperature and adjusts ring rate.
Temperature and Pressure Gauge
Allows the user to monitor system temperature and pressure.
Electrical field connections with terminal strips
The electrical cover allows easy access to the clearly marked line
voltage and low voltage terminal strips to facilitate wiring the boiler.
11 12
9
8
7
65
Nr. Quantity Description
1 1 Condensing Gas Boiler
2 1 Condensate Drain Pipe
3 1 Upper Bracket
4 2 Assembly Screws (Fischer Type SX )
5 1 CH Pressure Relief Valve
6 1 3” CPVC Pipe, 5” Long
7 2 + 2 2”Vent Screen + 3”Vent Screen
8 1 Tridicator
9 1 Lower Bracket
10
1 Installation Manual (This Document)
1 User’s Information Manual
1 Connectivity Quick Start Guide
1 LP Conversion Instructions
1 Warranty
1 Programming Guide
11 1 LP Gas Conversion Kit
12 1 Outdoor sensor Kit
13 1 3/4” Cap (Not Included with Combis, and not shown)
UNCRATING THE BOILER - Any claims for damage or shortage in
shipment must be led immediately against the transportation
company by the consignee.
NOTICE
1
2
34
PART 2

420011303900 - Revision Date 2.28.22
11
Condensate Collection System
This boiler is a high eciency appliance and will produce condensate.
The condensate collection system has a oat switch which monitors
condensate level and prevents condensate from backing up into
the combustion system. Inside the collection system is a built in trap
which seals the combustion system from the connected drain. This
condensate should be neutralized to avoid damage to the drainage
system or piping.
Outdoor Sensor
Monitors outdoor temperature and adjusts unit set point to provide
greater eciency.
0-10 Volt Input / 4-20 mA Input (with Optional Analog Clip-In
Board, part # 3319457)
Allows the installer to connect a BMS (Building Management System)
to control the boiler.
Condensate Trap
The condensate trap prevents condensates and heat exchanger
exhaust backing up into the cabinet.
Pump Service Mode
Allows manual operation of pumps to commission system and check
pump operation.
Internal By-Pass Valve
Protects the boiler from damage in low ow conditions.
Internal ECM Pump
The internal ECM Pump uses less electricity than standard pumps,
providing high performance operation.
DHW Temperature Sensor
Monitors DHW outlet temperature. The control adjusts boiler ring rate
to match the DHW supply temperature to the set point.
DHW Flow Meter
Monitors DHW ow rate.
B. Optional Equipment
Optional equipment available from HTP (and Part #):
• Indirect Sensor (7250P-325)
• System Sensor (7250P-324)
• 3” PVC Concentric Vent Kit (KGAVT0601CVT)
• 3” Stainless Steel Vent Termination Kit (V1000)
• 3” Polypro Vent Kit (8400P-001)
• 3” Polypro Pipe
(33’ length # 8400P-002, 49.5’ length # 8400P-003)
• Condensate Neutralizer (7450P-212)
• Condensate Removal Pump (554200)
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 boiler 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 boiler.
Carefully consider installation when determining boiler location.
Please read the entire manual before attempting installation. Failure
to properly take factors such as boiler venting, piping, condensate
removal, and wiring into account before installation could result in
wasted time, money, and possible property damage and personal
injury.
PART 3 - PREPARE THE BOILER FOR
INSTALLATION
This boiler is certied for indoor use only. DO NOT INSTALL
OUTDOORS. Outdoor installations ARE NOT covered by warranty.
Failure to install the boiler indoors could result in property damage,
severe personal injury, or death.
A. Locating the Boiler
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 boiler or components due to incorrect operating
conditions IS NOT covered by product warranty.
This boiler must be installed upright in the vertical position as
described in this manual. DO NOT attempt to install this boiler in any
other orientation. Doing so will result in improper boiler 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
This boiler 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.
Circulators suitable for DHW applications must be used.
Failure to take precautions could result in property damage, severe
personal injury, or death.
CAUTION
!
WARNING
!
WARNING
PART 2 - 3

420011303900 - Revision Date 2.28.22
12
2. Check for nearby connections to:
• System water piping
• Venting connections
• Gas supply piping
• Electrical power
• Condensate drain
3. Check area around boiler. Remove any combustible materials,
gasoline, and other ammable liquids.
Failure of the boiler or components due to incorrect operating
conditions IS NOT covered by product warranty.
Failure to keep the boiler area clear and free of combustible
materials, liquids, and vapors can result in substantial property
damage, severe personal injury, or death.
4. Gas control system components must be protected from dripping
water during operation and service.
5. If the boiler is to replace an existing boiler, check for and correct
any existing system problems, such as:
• System leaks
• Location that could cause the system and boiler to freeze and leak
• Incorrectly sized expansion tank
6. Clean and ush system when reinstalling a boiler.
Always take future maintenance into consideration when locating
the boiler. If the boiler is located in an installation location with
limited clearances, it may be necessary to remove the boiler
from the space to perform maintenance. Failure to consider
maintenance when determining installation location could result
in property damage.
Do not introduce toxic chemicals, such as antifreeze or appliance
treatments, into any piping meant for potable water purposes.
Do not connect DHW connections to any heating systems or
components that have been previously used for nonpotable
applications.
Failure to follow these instructions could result in serious personal
injury or death.
Ensure that all piping and components connected to the appliance
are suitable for potable water applications.
B. Leveling
The boiler must be installed level for condensate to properly ow
out of the collection system. Failure to do so will result in improper
appliance operation.
Correct installation Incorrect installation
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 boiler model and serial number.
NOTE: A combustible door or removable panel is acceptable front
clearance.
Figure 3 - Proper leveling
All boilers eventually leak. Locate the boiler 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 boiler 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. If the boiler is installed in a location where
a leak could cause damage, it is required to provide containment
measures. Such measures include but are not limited to: a properly
sized drain pan installed beneath the boiler and piped to an open
drain line, or installing the boiler on a concrete oor pitched to a
free owing drain. Failure to provide containment measures is the
sole responsibility of the owner and/or installer. 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 BOILER INSTALLATION WHERE A LEAKAGE OF WATER
COULD RESULT IN PROPERTY DAMAGES.
CAUTION
The service life of the boiler’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 boiler components. In these environments, boilers
must not be installed using direct vent systems which draw outdoor
air for combustion. Such boilers must be installed using room air for
combustion. Indoor air will have a much lower relative humidity,
and hence potential corrosion will be minimized.
!
WARNING
CAUTION
CAUTION
CAUTION
!
WARNING
PART 3

420011303900 - Revision Date 2.28.22
13
C. Clearances for Service Access
NOTE: If you do not provide the minimum clearances shown in Figure
4 and Table 6 it might not be possible to service the boiler without
removing it from the space.
C
A
D
B B
Dimension Description Clearance
ATop 14” (355.6 mm)
BRight or Left Side 2” (50.8 mm)
CFront 18” (457.2 mm)
DBottom 12” (304.8 mm)
Not Displayed Back 0” (0 mm)
Table 6 - Minimum Installation and Service Clearances
NOTE: For closet installations, a combustible door or removable
panel is acceptable front clearance. A 3” minimum clearance must be
provided from the appliance front cover to the removable panel or
combustible door.
Minimum Clearances from Combustible Materials
• Hot water pipes - at least 1”from combustible materials
• Exhaust vent pipe - at least 1”from combustible materials
Figure 4 - Minimum Clearances
Boiler Area Ventilation Air Openings - Closet Installations
If the boiler is installed in a closet or alcove the boiler area/room must
be ventilated.
EXCEPTION: If the boiler area/room has a volume of 150 ft3or greater,
ventilation of the boiler area/room is not required.
Each ventilation air opening must meet the minimum requirements
of 1 in2per 1000 BTU/hr., but not less than 100 in2. The lower ventila-
tion opening must be located within 6 in. of the oor, while the upper
opening must be located 6 in. from the top of the space.
If the boiler area has a volume less than 150 ft3, it is considered a Closet
or Alcove. In the US/Canada, PVC vent pipe and ttings SHALL NOT BE
USED within the closet or alcove. Only approved CPVC, Polypropylene, or
Stainless Steel vent pipe and ttings may be used. See Table 12 for a list
of approved materials. Under all circumstances proper ventilation must be
provided.
The space must be provided with correctly sized combustion/ventilation
air openings for all other appliances located in the space with the boiler.
For power venting installations using room air for combustion, refer to
the boiler venting section, this manual, for descriptions of conned and
unconned spaces. Do not install the boiler in an attic. The boiler cover
must be securely fastened to prevent the boiler from drawing air from the
boiler room. This is particularly important if the boiler 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.
Alcove Installations
Alcove installations have the same minimum dimensions as closet
installations, except the installation must be completely open to the
room at a distance no greater than 18 in. (457 mm) from the front of
the boiler and the room must be at least three (3) times the size of the
alcove. Provided these conditions are met, the boiler requires no extra
ventilation air openings to the space. If these conditions are not met,
follow the requirements for Closet Installations.
!
WARNING
!
WARNING
!
WARNING
D. Wall Mounting Considerations
These boilers are wall mounted. Use only the wall mounting instructions
included with this boiler.
Ensure the wall that the boiler is intended to be mounted on is
comprised of cement, brick, block, or wooden studs spaced 16” apart
from center. Ensure the wall is capable of supporting at least 150 lbs
(68 kgs).
If ooding is possible, elevate the boiler to prevent oodwater from
reaching the boiler.
Ensure the boiler is installed in a location that minimizes the risk of
water damage due to leaking valves, pumps, unions, etc.
The boiler may be installed on any suitable internal wall (suitable
sound-proong may be required when installing onto a stud partition
wall).
Ensure that the structure of the installation location is sucient to
support the full installed weight of the boiler, including water content
of the heat exchanger and related piping and components. If the
mounting location cannot support a minimum of 150 lbs. (68 kg), it
is recommended to locate the boiler in a mounting location that can
support the minimum weight. Failure to ensure the structure of the
installation location is structurally sound before installation of the
boiler and properly mount the boiler can result in structural failure,
substantial property damage, severe personal injury, or death.
Do not mount the boiler to a hollow wall.
1. Position the upper wall mounting bracket on the concrete wall.
Ensure the bracket is level. Then use the bracket as a template to
mark four (4) drilling holes on the wall - two (2) on each side of the
bracket. See Figure 5 for details.
2. Drill and plug the wall. Then secure the upper mounting bracket
using the provided Fischer S 10x50screws. Ensure the bracket is
level.
3. Install the lower mounting bracket on the boiler. Then hang the
boiler on the upper mounting bracket. Ensure the boiler is level.
Then use the lower bracket to mark the lower bracket drilling holes.
4. Drill and plug the wall and secure the lower mounting bracket
using eld provided screws. Then adjust the lower mounting
bracket on the boiler. Ensure the boiler is installed plumb. Then
tighten the bracket to the boiler.
Thisboileristooheavyforonepersontolift.It ishighlyrecommended
to install the boiler with two people. Use caution as to not drop the
boiler, which could damage the boiler and cause property damage
and/or severe personal injury. Verify that the boiler is properly and
securely mounted before leaving unsupervised. Failure to comply
with the above and properly mount the boiler could result in
substantial property damage, severe personal injury, or death.
E. Wall Mounting Instructions
1. Mounting to a Concrete Wall
PART 3

420011303900 - Revision Date 2.28.22
14
2. Mounting to a Wood Studded Wall
If the boiler is not installed upright, vertically plumb, and level,
improper and unsatisfactory operation may occur, causing
excessive condensation build-up, nuisance fault codes, and
unnecessary maintenance.
1. Position the upper wall mounting bracket on the wall. Ensure the
bracket is level and the drilling holes are on stud. Then use the
bracket as a template to mark four (4) drilling holes on the wall -
two (2) on each side of the bracket. See Figure 6 for details.
2. Drill and plug the wall. Then secure the upper mounting bracket
using the provided (Fischer S 10x50) screws and eld provided
washers for wood mounting.
3. Install the lower mounting bracket on the boiler. Then hang the
boiler on the upper mounting bracket. Ensure the boiler is level.
Then use the lower bracket to mark the lower bracket drilling holes.
4. Drill and plug the wall and secure the lower mounting bracket
using eld provided screws. Then adjust the lower mounting
bracket on the boiler. Ensure the boiler is installed plumb. Tighten
the bracket to the boiler.
Use extreme care not to drop the boiler or cause bodily injury while
lifting or mounting the boiler onto the wall mount bracket.
Failure to follow these instructions could result in property damage,
severe personal injury, or death.
This wall mounting system is not seismic rated and should not be
applied as such. Failure to comply with the above and properly
mount the boiler could result in substantial property damage,
severe personal injury, or death.
The manufacturer cannot anticipate all installation conditions. These
instructions and included parts may not apply to wall-mounting the
appliance at your installation location. The appliance must be properly
and securely mounted by a qualied installer according to installation
conditions, the technical specications of the appliance, and to meet AHJ
/ building code requirements. All applicable permits must be obtained
before installing the appliance. Failure to follow these instructions could
result in property damage, severe personal injury, or death. Any damages
resulting from improper installation are not covered by product warranty.
Figure 5 - Mounting to a Concrete Wall
Figure 6 - Mounting the Bracket on 16” Center Studs
16 “
F. Residential Garage and Closet Installations
Check with your local Authority Having Jurisdiction for requirements
when installing the boiler in a garage or closet. Please read the
entire manual before attempting installation. Failure to properly
take factors such as boiler venting, piping, condensate removal,
and wiring into account before installation could result in wasted
time, money, and possible property damage and personal injury.
Precautions
If the boiler is located in a residential garage, per ANSI Z223.1:
• Mount the bottom of the boiler a minimum of 18” above the oor
of the garage to ensure the burner and ignition devices are well
o the oor.
• Locate or protect the boiler so it cannot be damaged by a moving
vehicle.
G. Exhaust Vent and Intake Pipe
The boiler is rated ANSI Z21.13 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 boiler. Failure to vent the boiler in accordance
with the provided venting instructions will void the warranty.
The space must be provided with correctly sized combustion/
ventilation air openings for all other appliances located in the
space with the boiler. For power venting installations using room
air for combustion, refer to the boiler venting section, this manual,
for descriptions of conned and unconned spaces. Do not install
the boiler in an attic. Failure to comply with these warnings could
result in substantial property damage, severe personal injury, or
death.
Failure to vent the boiler properly will result in serious personal
injury or death.
Do not attempt to vent this boiler 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.
!
WARNING
!
WARNING
!
WARNING
!
WARNING
DANGER
!
CAUTION
CAUTION
PART 3

420011303900 - Revision Date 2.28.22
15
Vents must be properly supported. Boiler exhaust and intake
connections are not designed to carry heavy weight. Vent support
brackets must be within 1’ of the boiler and the balance at 4’
intervals. Boiler must be readily accessible for visual inspection for
rst 3’from the boiler. Failure to properly support vents could result
in property damage, severe personal injury, or death.
The exhaust discharged by this boiler 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 boiler 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 boiler 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 7.
This boiler 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 7.
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 boiler input. Never obstruct the
supply of combustion air to the boiler. If the boiler is installed in areas
where indoor air is contaminated (see Table 7) it is imperative that the
boiler be installed as direct vent so that all combustion air is taken
directly from the outdoors into the boiler intake connection.
Unconfined 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.
Confined 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.
Whendrawingcombustionair from inside aconventionally 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.
2. Power Venting, Indoor Combustion Air in Confined or
Unconfined Space
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 7.
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.
H. Carbon Monoxide Detectors
!
WARNING
!
WARNING
!
WARNING
CAUTION
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.
PART 3

420011303900 - Revision Date 2.28.22
16
I. Prevent Combustion Air Contamination
Install intake air piping for the boiler 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 7. Contaminated air will damage the boiler, 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.
NOTE: DAMAGE TO THE BOILER CAUSED BY EXPOSURE TO
CORROSIVE VAPORS IS NOT COVERED BY WARRANTY. (Refer to
the limited warranty for complete terms and conditions.)
Areas Likely to Have
Contaminants Products to Avoid
Dry cleaning / laundry areas and
establishments
Spray cans containing
uorocarbons
Swimming pools Permanent wave solutions
Metal fabrication plants Chlorinated waxes / cleaners
Beauty shops Chlorine-based swimming pool
chemicals
Refrigeration repair shops Calcium chloride used for
thawing
Photo processing plants Sodium chloride used for water
softening
Auto body shops Refrigerant leaks
Plastic manufacturing plants Paint or varnish removers
Furniture renishing areas and
establishments Hydrochloric or Muriatic acid
New building construction Cements and glues
Remodeling areas Antistatic fabric softeners used
in clothes dryers
Garages and workshops
Chlorine-type bleaches, laundry
detergents, and cleaning
solvents
Adhesives used to fasten
building products
Table 7 - Products and Areas Likely to Have Contaminants
Figure 7 - CO Warning Label
J. Removing a Boiler 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 boiler 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 boiler, 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 boiler 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.
!
WARNING
!
WARNING
PART 3

420011303900 - Revision Date 2.28.22
17
K. Technical Specifications
Table 8 - Technical Specifications
NOTES:
1Listed Input and Output Ratings are at minimum vent lengths at an altitude of 0 - 2000 ft. Numbers will be lower with longer venting and/or altitudes
greater than 2000 ft.
2Ratings based on standard test procedures prescribed by the US Department of Energy.
3The ELU requires a special venting system. Use only the vent materials and methods detailed in these installation instructions.
Model ELU-150WBN ELU-199WBN ELU-199WCN
Type Boiler Combi
Installation Indoor, Wall Hung, Fully Condensing
Minimum / Maximum Input (Btu/Hr)115,000 / 150,000 NG 19,700 / 197,000 NG 19,700 / 197,000
LP 19,200 / 192,000 LP 19,200 / 192,000
DOE AFUE2 (%) 95 95 95
Heating Capacity1, 2 (MBH) 139 184 184
Net AHRI Rating, Water (MBH)2121 160 160
Hot Water Capacity
35oF Rise N/A N/A 10.5
45oF Rise N/A N/A 8.2
77oF Rise N/A N/A 4.8
Flue System Category IV, Sealed Combustion Direct Vent, Power Vent
Minimum - Maximum Exhaust Vent Run32” (6 - 100 feet) / 3” (6 - 150 feet)
Minimum - Maximum Intake Air Pipe Run32”(0 - 100 feet) / 3”(0 - 150 feet)
Approved Exhaust Vent Materials3PVC, CPVC, PP, Stainless Steel
Shipping Weight (lbs) 115 125 130
Gas Supply
Pressure
NG 3.5” to 10.5” WC
LP 8” to 13” WC
Power Supply 120V, 60 Hz, less than 12A
General Operating Conditions Ambient Temperature Range: 33 – 104oF (0.6 – 40oC)
Product Approvals and Requirements: ANSI Z21.13 / CSA 4.9
Ignition System Direct Electronic Spark Ignition / Flame Rectication
Burner System Premixed Fuel Modulation / Stainless Steel Burner
Gas Valve System Air Ratio Valve
Dimensions
(in Inches)
W19.75”
H38.25”
D18.5”
Approx. Full Boiler Weight (lbs) 115 130 135
Boiler Water Content (Gallons) 2 2.7
Boiler Setpoint Temperature Range 68 – 122oF Low Temperature / 86 - 179oF High Temperature
DHW Indirect Setpoint Temperature Range 104 – 149oF
DHW Setpoint Range (Combi Models) 97 – 140oF
Water Pressure (PSI)
Heat Exchanger MAWP 50
Pressure Relief Valve 30
DHW Max Pressure N/A N/A 150
Control Panel / Main Controller AristonThermo LCD Display / AristonThermo GALEVO2 Control
Connection
Sizes
CH Supply / Return 1 1/4”Male NPT
DHW Inlet / Outlet 3/4” Male NPT
Gas Inlet 3/4” Male NPT
Materials Cabinet Painted and Galvanized Steel
Heat Exchanger Type 441 Stainless Steel Water Tube
Safety Devices Flame Rectier Probe, Temperature Limit Control (190oF), Water Pressure Switch (Min. 8 PSI), Freeze
Protection, Condensate Trap, Flue Temperature High Limit Sensor (210oF)
PART 3

420011303900 - Revision Date 2.28.22
18
Figure 8 - Boiler Dimensions - NOTE: All Dimensions Are Approximate
Model Boiler Models Model Combi Models
A - Central Heating Supply 1 1/4” NPT A - Central Heating Supply 1 1/4” NPT
B - Supply to Indirect Water Heater 3/4” NPT B - Domestic Hot Water Outlet 3/4” NPT
C - Gas Inlet 3/4” NPT C - Gas Inlet 3/4” NPT
DN/A D - Domestic Hot Water Inlet 3/4” NPT
E - Central Heating Return 1 1/4” NPT E - Central Heating Return 1 1/4” NPT
F - Pressure Relief Valve 3/4” NPT F - Pressure Relief Valve 3/4” NPT
Table 9 - Boiler Connection Sizes
34 1
8
"
19 3
4
"
2 1
4
"
3"
2 5
8
"
2 5
8
"
3"
3 5
8
"
2 3
4
"
3 3
4
" 9 3
4
" 6 3
8
"
38 1
4
"
1 7
8
"
A
B C D E
F
18 1
2
"
6 3
8
"
2 1
2
"
8 1
4
"
3 5
8
"
7 3
4
"
PART 3

420011303900 - Revision Date 2.28.22
19
Model Components
Figure 9 - Boiler Component Locations and Descriptions
24
13
20
1
2
3
6
7
9
8
26
10
16
17
12
15
11
18
19
21
22
5
23
25
1. Pressure relief valve
2. Air purge valve
3. Boiler outlet temperature sensor
4. Air pressure switch
5. Flue gas temperature sensor
6. Main heat exchanger
7. Flame detection electrode
8 Silencer
9. Junction box
10. DHW Heat Exchanger (Combi Models Only)
11. Condensate trap
12. Gas valve
13. Control panel
15. Circulation Pump
16. DHW Flow Sensor (Combi Models Only)
17. Water pressure switch
18. Modulating Fan
19. Boiler inlet temperature sensor
20. Frame
21. Ignition electrode
22. Spark generator
23. Combustion Analysis Test Point
24. Air intake connection
25. Exhaust vent connection
26. Diverter valve
PART 3

420011303900 - Revision Date 2.28.22
20
Figure 10 - Water Circuit Diagrams
A
BCD E
A
C
E
B
D
1. Pressure relief valve
2. Air purge valve
3. Boiler outlet temperature sensor
4. DHW Temperature Sensor
5. Flue gas temperature sensor
6. Main heat exchanger
7. Flame detection electrode
8 Silencer
10. DHW heat exchanger (Combi Models Only)
11. Condensate trap
12. Gas valve
15. Circulation Pump
16. DHW Flow Sensor (Combi Models Only)
17. Water pressure switch
18. Modulating Fan
19. Boiler inlet temperature sensor
21. Ignition electrode
24. Air intake connection
25. Exhaust vent connection
26. Diverter valve
27. By-pass
29. Pressure gauge
Combi Models Boiler Models
CAPTION
A Central Heating Supply D DHW Cold Inlet
B DHW Hot outlet E Central Heating (and Indirect Water Heater) Return
C Gas inlet F Indirect Water Heater Supply
F
PART 3