NTI TRX085 Installation manual

TRX
TRX
Residential Condensing Gas Boiler
Installation
Start-Up
Maintenance
Parts
Warranty
TRX085
TRX120
TRX110C
TRX150C models
THIS MANUAL MUST ONLY BE USED BY A QUALIFIED 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.
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 manufacturer reserves the right to make product changes or updates without
notice and will not be held liable for typographical errors in literature.
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.
WARNING
Heat Exchanger Bears the ASME “H” Stamp
DANGER
NOTICE
Revision Date 6.25.20

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.
WARNING

3
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.
CAUTION
CAUTION
NOTICE
WARNING
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.
SPECIAL ATTENTION BOXES
DANGER

4
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, NTI 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 ring
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
eciency operation possible. Such high eciency 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 Curve
(sensor response curve) in the boiler software.
• This feature may be over-ridden as described below in
specic 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.
WARNING
NOTICE
NOTICE

5
Table of Contents
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 8
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 12
Part 3 - Prepare the Boiler for Installation 13
A. Locating the Boiler 13
B. Leveling 14
C. Clearances for Service Access 14
D. Wall Mounting Considerations 15
E. Wall Mounting Instructions 15
1. Mounting to a Concrete Wall 15
2. Mounting to a Wood Studded Wall 16
F. Residential Garage and Closet Installations 17
G. Exhaust Vent and Intake Pipe 17
1. Direct Vent of Exhaust and Intake 17
2. Power Venting, Indoor Combustion Air in Conned or Unconned Space
17
H. Carbon Monoxide Detectors 17
I. Prevent Combustion Air Contamination 18
J. Removing a Boiler from a Common Vent System 18
K. Technical Specications 19
Part 4 - Water Piping 24
A. General Plumbing Information 24
B. Backow Preventer 24
C. Expansion Tank 24
D. Piping the Boiler 24
E. Internal Circulation Pump 26
F. By-Pass Valve 26
G. CH and DHW Pressure Relief Valves 26
H. Air Elimination Device 28
I. Low Water Cut-O (Field Supplied) 28
J. Applications* 28
K. Floor Drying Function 35
Part 5 - Venting 36
A. General 36
B. Approved Materials for Exhaust Vent and Intake Pipe 37
C. Additional Requirements for Installation in Canada 37
D. Exhaust Vent and Intake Pipe Location 38
E. Exhaust Vent and Intake Pipe Sizing 39
F. Tightening Boiler Collar to Exhaust Vent and Intake Pipe 39
G. Exhaust Vent and Intake Pipe Installation 40
H. Applications 42
1. Direct Vent Installation of Exhaust and Intake 42
2. Venting Through an Existing System 48
3. Power Venting, Indoor Combustion Air in Conned or Unconned Space
49
Part 6 - Installing the Condensate Drain 50
Part 7 - Connecting Electrical Service 51
A. Wiring 51
1. Removing the Power Cord (To Hard Wire the Boiler) 52
2. Connecting Power (120V) for DHW and CH Circulators 53
3. Low Voltage Wiring Connections 53
4. Room Thermostat Wiring Connections 54
5. Outdoor Sensor Connections 54
6. Aquastat (Default) and Tank Sensor (Optional) Connections (non-Combi
Models) 54
B. Internal Wiring Details 55
Part 8 - Gas Connections 59
A. Gas Pipe Sizing Tables 59
1. Gas Pipe Sizing 59
2. Natural Gas Pipe Sizing 59
3. LP (Liquid Propane) Gas Pipe Sizing 59
B. Gas Connection Requirements 59
C. Additional Precaution for Excess Flow Valve (EFV) 60
D. Checking Gas Pressure at the Boiler for Proper 60
Operation 60
Part 9 - Controls 61
A. Control and Display Overview 61
B. Ignition Procedure 62
C. Central Heating (CH) Temperature Adjustment 62
D.
Domestic Hot Water (DHW) Temperature Adjustment 62
E. User Menu 63
F. INFO Menu 64
G . Date and Time (If ITIME is set to OFF) 64
H. Automatic Temperature Control (AUTO) 65
I. Type of Temperature Control 66
J. Slope of Outdoor Reset Curve 66
K. Parallel Shift of Reset Curve 67
L. Auto Boost 67
M. Room Temperature Day /Night 68
N. Time Programs – Heating Schedule 68
O. Automatic Summer / Winter Changeover 68
P. Technical Menu - Access and Navigation 69
Q. Technical Menu - Menu Structure 70
R. Technical Menu - Complete Menu 71
Part 10 - Start-Up Preparation 79
A. Check / Control Water Chemistry 79
B. Check for Gas Leaks 79
C. Freeze Protection (When Used) 79
D. System Water Fill, Purge, and Test 80
E. Purge Air from DHW System 80
F. Check Thermostat Circuit(s) 80
G. Condensate Removal 80
Part 11 - Start-Up 82
A. First Ignition 82
B. Combustion Checking Procedure 83
C. Checking Combustion Parameters 85
D. Converting the Appliance from Natural Gas to Propane Operation
85
Part 12 - Installation Checklist 86
Part 13 - Troubleshooting 88
A. Boiler Protection Devices 88
1. Blocking Error 88
2. Lockout Error 88
3. Malfunction Warning 88
B. Boiler Error Codes 89
Part 14 - Maintenance 93
A. Procedures 93
B. Maintenance That May be Performed by the User 93
C. Maintenance Only to be Performed by a Qualied Service Technician
94
D. Replacing Components 98
E. After Maintenance is Complete 101
Part 15 - Maintenance Report 101
Part 16 - Shutdown 103
A. Shutdown Procedure 103
B. Failure to Operate 103
C. Important 103
Part 17 - Maintenance Notes 104
Customer Installation Record Form 107

6
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 offset” 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
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-off valve
and how to operate it. Immediately close the gas shut-off valve
if the appliance is subjected to re, overheating, ood, physical
damage, or any other damaging condition that might affect 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 off 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.

7
Part 1 - General Safety Information
B. Improper Combustion
WARNING
WARNING
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 NTI boiler with parts not manufactured by NTI 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 cutoff 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.
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.
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.
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.
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. NTI 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.
CAUTION
NOTICE
WARNING
WARNING
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 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.
• 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.
• 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.

8
Part 1 - General Safety Information
F. CH and DHW Loop Water Chemistry Requirements
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.
Chemical imbalance of the water supply may affect ef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 affect
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.
CAUTION
CAUTION
CH Loop Total Water Hardness Specications
Contaminant Maximum Allowable Level
Total Hardness 120 mg/l
(7 grains/gallon)
DHW Loop Total Water Hardness Specications
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 Specications
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 1 - Water Quality Specications
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%,
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: NTI DOES NOTWARRANTTHE 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.
WARNING
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)
Table 2 - Freeze Protection Detail

9
Part 1 - General Safety Information
CAUTION
WARNING
I. High Elevation Installations
Natural gas at high elevation might contain less heating value than
the typical 1,000 BTU/cu ft and therefore can cause an improper
air / gas mixture 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.
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.
On TRX085 / TRX120 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.
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

10
Part 2 - Before You Start
Components included with the boiler:
A. What’s in the Box
UNCRATING THE BOILER - Any claims for damage or shortage in
shipment must be led immediately against the transportation
company by the consignee.
Remove the boiler from the packaging. Remove the accessory box
from the boiler. Take care to place the boiler in a safe location prior to
installation to prevent damage to the mechanical connections.
TEMPLATE
QSG
TRX
TRX
Residential Condensing Gas Boiler
Spare Parts
Exploded view
THIS MANUAL MUST ONLYBE USED BY A QUALIFIED INSTALLER / SERVICE
TECHNICIAN. READ ALL INSTRUCTIONS IN THIS MANUAL BEFORE
INSTALLING. PERFORM STEPS IN THE GIVEN ORDER. FAILURETO DO SO
COULD RESULT IN SUBSTANTIALPROPERTY DAMAGE, SEVERE PERSONAL
INJURY,OR DEATH.
Improperinstallation, adjustment, alteration, service, or maintenance could
voidproduc t warranty and cause property damage, severe personal injury,
ordeath.
California Proposition 65Warning: This product contains chemicals known
tothe State of California to cause cancer,bir th defects, or other reproductive
harm.
The manufacturer reserves the right to make product changes or updates without
noticeand will not be held liable for typographical errors in literature.
Thesurfaces of these products contac ted bypotable (consumable) water contain less
than0.25% lead by weight as required by the Safe Drinking Water Act, Section 1417.
WARNING
DANGER
NOTICE
Date6.25.20
TRX085
All models
THISCONTROL WAS CONVERTEDFOR USE WITH PROPANE GAS
Thisappliance has been converted for use with Propane Gas, in accordance with the
instructionsprovided with the Natural to Propane Conversion Kit
by______________________________________ , which accepts responsibility that
theconversion was performed properly.
Referencerating plate for PropaneInput and G as Pressure
420060882600
20
0 250
100 150
50 200
20
080
60
40
psi
TRX110C
1
2
3
12
13
14 15
4
55
6
7
8
9
10
11
TRX
TRX
Residential Condensing Gas Boiler
User’s
Information
Manual
User Operating
Instructions
IF THE INFORMATION IN THIS MANUAL IS NOT FOLLOWED EXACTLY,
A FIRE OR EXPLOSION MAY RESULT, CAUSING PROPERTY DAMAGE,
PERSONAL INJURY, OR LOSS OF LIFE. DO NOT STORE GASOLINE OR
OTHER FLAMMABLE VAPORS AND LIQUIDS IN THE VICINITYOF THIS OR
ANY OTHER BOILER.
WHAT TO DO IF YOUSMELL GAS
• Do not try to light any boiler.
• 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 fire department.
Installation and service must be provided by a qualified installer,
service agency, or the gas supplier.
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 manufacturer reserves the right
to make product changes or updates
without notice and will not be held
liable for typographical errors in
literature.
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.
NOTE TO CONSUMER:
PLEASE KEEP ALL INSTRUCTIONS
FOR FUTURE REFERENCE.
WARNING
NOTICE
HeatExchanger Bears the ASME “H” Stamp
TRX
TRX
Residential Condensing Gas Boiler
Installation
Start-Up
Maintenance
Parts
Warranty
THIS MANUAL MUST ONLY BE USED BY A QUALIFIED INSTALLER /
SERVICE TECHNICIAN. READ ALL INSTRUCTIONS IN THIS MANUAL
BEFORE INSTALLING. PERFORM STEPS IN THE GIVEN ORDER. FAILURE
TODO SO COULD RESULT IN SUBSTANTIAL PROPERTY DAMAGE,SEVERE
PERSONAL INJURY,OR DEATH.
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 manufacturer reserves the right to make product changes or updates
without notice and will not be held liable for typographical errors in literature.
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.
WARNING
HeatExchanger Bears the ASME “H” Stamp
DANGER
NOTICE
Connectivity
Quick Start Guide
TRX series
For Qualified Technician
Installation Instructions
TRX NATURAL TO PROPANE
CONVERSION INSTRUCTIONS
This conversion kit shall be installed by a qualified
service agency in accordance with the manufacturer’s
instructions and all applicable codes and requirements
of the authority having jurisdiction. If the information
in these instructions is not followed exactly, a fire, an
explosion or production of carbon monoxide may result
causing property damage, personal injury or loss of
life. The qualified service agency is responsible for the
proper installation of this kit. THE INSTALLATIONIS NOT
PROPER AND COMPLETE UNTIL THE OPERATIONOF THE
CONVERTED APPLIANCE IS CHECKED AS SPECIFIED IN
THE MANUFACTURER’S INSTRUCTIONS SUPPLIED WITH
THEKIT, WHICH NECESSITATESTHE USE OF A CALIBRATED
CO2/O2ANDCO COMBUSTION ANALYZER.
WARNING
Gas
Gas
14a
14f
14h
14i 15h
14b 14c
14d
14g
14e
15d
15a
15g
15e
15f
ACCESSORIES BOX
BOITE ACCESSOIRES
ForQualified Technician
InstallationInstruc tions
Pourtechnicien qualifié
instructionsd’installation
Read the code
Lirele code
code
ACCESSORIES BOX
BOITE ACCESSOIRES
ForQualified Technician
InstallationInstruc tions
Pourtechnicien qualifié
instructionsd’installation
Read the code
Lirele code
code
15b 15c
Figure 1 - Included with the Boiler - part a Table 4 - Included with the Boiler
NOTICE Nr. Quantity Description
ALL MODELS
1 1 Condensing Gas Boiler
2 1 Condensate Drain Pipe
3 1 Bracket
4 2 Assembly Screws (Fischer Type SX )
5 1+1 CH Pressure Relief Valve + Connection Tube
6 1 2”CPVC Pipe, 5.5”Long
7 1 Piping Bracket
8 1 Torx screw adapter
9 2 + 2 2”Vent Screen + 3”Vent Screen
10 1 Tridicator
11
1 Installation Manual (This Document)
1 User’s Information Manual
1 Connectivity Quick Start Guide
1 LP Conversion Instructions
1 Warranty
1 Installation Quick Start Guide
1 Replacement parts manual
1 Template
12 1 LP Gas Conversion Kit
13 1 Outdoor sensor Kit
14 1 Piping Adapter Kit - TRX085
14-a 1 + 1 Gas Adapter 3/4”+ 1 gas at
14-b 5 Gasket (2x1/2” + 2x3/4” + 1 x 1”)
14-c 2 Cap 1/2”
14-d 4 Additional Gasket (1x1/2” + 1x3/4”+ 1 x 1” + 1 gas at)
14-e 4 Clamp (2x3/4”+ 2x1”)
14-f 1 CH supply pipe 1”
14-g 1 Tank return pipe 3/4”
14-h 1 CH return pipe 1”
14-i 1 Accessory box components list
15 1 Piping Adapter Kit- TRX110C
15-a 1 + 1 Gas Adapter 3/4”+ 1 gas at
15-b 5 Gasket (2x1/2” + 2x3/4” + 1 x 1”)
15-c 4 Additional Gasket (1x1/2” + 1x3/4” + 1 x 1” + 1 gas at)
15-d 4 Clamp (2x3/4” + 2x1”)
15-e 1 CH supply pipe 1”
15-f 2 DHW outlet & inlet pipes 3/4”
15-g 1 CH return pipe 1”
15-h 1 Accessory box components list
16 1 Piping Adapter Kit - TRX120/ TRX150C
(see Fig. 2 - next page)
16-a 1 + 1 Gas Adapter 3/4”+ 1 gas at
16-b 6 Gasket (2x1/2” + 3x3/4” + 1 x 1”)
16-c 2 Cap 1/2”
16-d 4 Additional Gasket (1x1/2” + 1x3/4” + 1 x 1” + 1 GAS at )
16-e 1 CH supply pipe 1”
16-f 1 CH return pipe 1”
16-g 4 Clamp (2x3/4” + 2x1”)
16-h 1 DHW outlet pipe (150C)/Tank return pipe (120) 3/4”
16-i 1 DHW inlet ow restrictor (150C)1/2” x 3/4”
16-j 1 DHW inlet pipe 3/4”
16-jk 2 Accessory box components list

11
or
16e
16f
16h
16i
16j
16g
16k
Gas
16a 14b
14d
14c
ACCESSORIES BOX
BOITE ACCESSOIRES
ForQualified Technician
InstallationInstruc tions
Pourtechnicien qualifié
instructionsd’installation
Read the code
Lirele code
code
Part 2 - Before You Start
TRX150C / TRX120
Ø 1-1/8”
10" 1/16” (255 mm)
16” (406 mm)
Ø 1-1/8”Ø 7/8” Ø 7/8”
View from
the Front
6-11/16” (169 mm)
6-3/8” (162 mm)
2-3/16” (55 mm)
View from the Side
20
0
100 150
200
250
50
20
080
60
40
psi
Figure 2 - Included with the Boiler
Figure 3 - Adapter Kit Dimensions and
Specications - Included with Adapter Kit
How the Boiler Operates
TRX 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 eld 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.

12
Part 2 - Before You Start
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 and Air Pressure Switch
The condensate trap and air pressure switch prevent condensate and
heat exchanger exhaust from backing up into the boiler.
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.
B. Optional Equipment
Optional equipment available from NTI (and Part #):
• System Sensor (84010)
• 3” PVC Concentric Vent Kit (84634)
• 3” PVC Low Prole Vent Kit (84357)
• 2” PVC Low Prole Vent Kit (85062)
• Tank Sensor (84632)
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.

13
Part 3 - Prepare the Boiler for Installation
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.
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.
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.
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.
Ensure that all piping and components connected to the appliance
are suitable for potable water applications.
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 CAUTION
CAUTION
WARNING
WARNING
WARNING
WARNING
WARNING
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.
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.
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.
Failure of the boiler 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 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.
Failure to follow these instructions could result in serious personal
injury or death.

14
Part 3 - Prepare the Boiler for 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.
CAUTION
CAUTION
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
shutoff 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.
The boiler must be installed level for the condensate to properly
ow out of the collection system. Failure to do so will result in
improper appliance operation.
B. Leveling
C. Clearances for Service Access
NOTE: If you do not provide the minimum clearances shown in Figure
5 and Table 5 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 5 - 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
Correct installation Incorrect installation
Figure 4 - Proper levelling
Figure 5 - Minimum Clearances
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.
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 11 for a list of approved materials. Under all circumstances
proper ventilation must be provided.
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
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.

15
Part 1 - General Safety Information
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 suf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.
WARNING
Do not mount the boiler to a hollow wall.
This boiler is too heavy for one person to lift. It is highly recommended
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.
WARNING
Position the paper template on the concrete wall to locate the positions
of the hanging bracket and piping bracket.
Drill and plug the wall and secure the hanging bracket using the screws
provided (scher S 10x50). Ensure the hanging bracket is level.
Secure the piping bracket on the concrete wall. Use suitable hardware.
E. Wall Mounting Instructions
1. Mounting to a Concrete Wall
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.
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.
WARNING
STUDSTUD
Plywoodboard
Dimensions:
24"wide x 48" high x 1/2" thick
(239,75mm)
(13,1mm)
(226,65mm)
(65mm) (65mm)
(67mm)(67mm)
(131,76mm)
(87,2mm) (87,2 mm)(87,6mm) (87,6mm)
3-7/16”
2-9/16”
8-15/16”
5-3/16”
2-9/16”
1/2”
9-7/16”
2-5/8” 2-5/8”
3-7/16”
1-1/8”
9/16”
3-7/16” 3-7/16”
(1108,15mm)
(745mm)
(146,26mm)
(110mm)
43-5/8”
29-5/16”
(400mm)
(120mm)
(406,4mm)
(120mm)
(34,2mm)
(136,5mm)
15-3/4”
5-3/4”
4-5/16”
4-3/4” 4-3/4”
1-3/8”
5-3/8”
(330mm)
13”
16”
20
0
100 150
200
250
50
20
080
60
40
psi
WARNING
THEMANUFACTURER CANNOT ANTICIPATEALL INSTALLATION CONDITIONS.THESE INSTRUCTIONS AND
INCLUDEDPARTS MAYNOT APPLY TOWALL-MOUNTING THE BOILER ATYOUR INSTALLATION LOCATION.
THEBOILER MUST BE PROPERLY AND SECURELY MOUNTED BY A QUALIFIEDINSTALLER ACCORDING TO
INSTALLATIONCONDITIONS, THETECHNIC AL SPECIFICATIONSOF THE APPLIANCE, AND TO MEET AHJ /
BUILDINGCODEREQUIREMENTS. ALL APPLICABLE PERMITS MUST BE OBTAINED BEFORE INSTALLINGTHE
BOILER. FAILURETO FOLLOW THESE INSTRUCTIONS COULD RESULT IN PROPERTY DAMAGE, SEVERE
PERSONAL INJURY,OR DEATH. ANY DAMAGES RESULTING FROM IMPROPER INSTALLATIONARE NOT
COVEREDBY PRODUCT WARRANTY.
MOUNTINGTO A WOOD STUDDED WALL
To install the boiler on a standard wood studded wall a plywood board is required.The minimum
dimensionsof the plywood board are: 24" wide x 48" high x 1/2" thick.
Useat least fourteen (14) #12 x 3" (3/16" x 3") round head tapping screws to secure the plywood board to
thestudded wall.
Positionthepaper template on the concrete wall to locate the positions of the hanging bracket and piping
bracket.
Drilland plug the wall and secure the hanging bracket using the screws provided (fisher S 10x50). Ensure
thehanging bracket is level.
Securethe piping bracket on the concrete wall. Use suitable hardware.
WALLMOUNTING INSTRUCTIONS
Afterthe plywood board has been installed to the studs, position the paper template on the plywood.
Locatethe positions of the hanging bracket and piping adapter bracket. Position the wall mounting and
pipingadapter brackets. Ensure the brackets are level.Then mark the bracket drilling holes.
Mountthe boiler bracket on the plywood board. Use the hardwaredelivered with the boiler
(fisherS 10x50) and washers for wood mounting.
Mount the piping bracket on the plywood board. Use suitable hardware .
Figure 6 - Mounting to a concrete wall
Part 3 - Prepare the Boiler for Installation

16
Part 1 - General Safety Information
CAUTION
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.
2. Mounting to a Wood Studded Wall
16 “
To install the boiler on a standard wood studded wall with 16” centers,
a plywood board is required. The minimum dimensions of the plywood
board are: 24”wide x 48” high x 1/2”thick.
Use at least fourteen (14) #12 x 3” (3/16” x 3”) round head tapping
screws to secure the plywood board to the studded wall.
Figure 7 - Mounting a plywood board
Part 3 - Prepare the Boiler for Installation
After the plywood board has been installed to the studs, position the
paper template on the plywood.
Locate the positions of the hanging bracket and piping adapter
bracket. Position the wall mounting and piping adapter brackets.
Ensure the brackets are level. Then mark the bracket drilling holes.
Mount the boiler bracket on the plywood board. Use the hardware
delivered with the boiler (scher S 10x50) and washers for wood
mounting.
Mount the piping bracket on the plywood board. Use suitable
hardware .
16 “
STUDSTUD
Plywood board
Dimensions:
24" wide x 48" high x 1/2" thick
(239,75 mm)
(13,1 mm)
(226,65 mm)
(65 mm) (65 mm)
(67 mm)(67 mm)
(131,76 mm)
(87,2 mm) (87,2 mm)(87,6 mm) (87,6 mm)
3-7/16”
2-9/16”
8-15/16”
5-3/16”
2-9/16”
1/2”
9-7/16”
2-5/8” 2-5/8”
3-7/16”
1-1/8”
9/16”
3-7/16” 3-7/16”
(1108,15 mm)
(745 mm)
(146,26 mm)
(110 mm)
43-5/8”
29-5/16”
(400 mm)
(120 mm)
(406,4 mm)
(120 mm)
(34,2 mm)
(136,5 mm)
15-3/4”
5-3/4”
4-5/16”
4-3/4” 4-3/4”
1-3/8”
5-3/8”
(330 mm)
13”
16”
20
0
100 150
200
250
50
20
080
60
40
psi
WARNING
THE MANUFACTURERCANNOT ANTICIPATE ALL INSTALLATIONCONDITIONS. THESE INSTRUCTIONS AND
INCLUDED PARTSMAY NOT APPLYTO WALL-MOUNTINGTHE BOILER AT YOUR INSTALLATIONLOCATION.
THE BOILER MUST BE PROPERLYAND SECURELY MOUNTED BY A QUALIFIED INSTALLER ACCORDINGTO
INSTALLATIONCONDITIONS, THE TECHNICAL SPECIFICATIONS OF THE APPLIANCE,AND TO MEET AHJ /
BUILDINGCODE REQUIREMENTS. ALL APPLICABLE PERMITS MUST BE OBTAINED BEFORE INSTALLINGTHE
BOILER. FAILURE TO FOLLOW THESE INSTRUCTIONS COULD RESULT IN PROPERTY DAMAGE, SEVERE
PERSONAL INJURY, OR DEATH. ANY DAMAGES RESULTING FROM IMPROPER INSTALLATION ARE NOT
COVEREDBY PRODUCT WARRANTY.
MOUNTINGTO A WOOD STUDDED WALL
To install the boiler on a standard wood studded wall a plywood board is required. The minimum
dimensions of the plywood board are: 24" wide x 48" high x 1/2" thick.
Use at least fourteen (14) #12 x 3" (3/16" x 3") round head tapping screwsto secure the plywood board to
the studded wall.
Positionthe paper template on the concrete wall to locate the positions of the hanging bracket and piping
bracket.
Drill and plug the wall and secure the hanging bracketusing the screws provided (fisher S 10x50). Ensure
the hanging bracketis level.
Secure the piping bracketon the concrete wall. Use suitable hardware.
WALLMOUNTING INSTRUCTIONS
After the plywood board has been installed to the studs,position the paper template on the plywood.
Locate the positions of the hanging bracket and piping adapter bracket.Position the wall mounting and
piping adapter brackets.Ensure the brackets are level. Then mark the bracket drilling holes.
Mount the boiler bracket on the plywood board. Use the hardware delivered with the boiler
(fisher S 10x50) and washers for wood mounting.
Mount the piping bracket on the plywood board. Use suitable hardware .
16 “
16 “
Figure 8 - Mounting the hanging bracket and piping bracket

17
Part 1 - General Safety InformationPart 3 - Prepare the Boiler for Installation
F. Residential Garage and Closet Installations
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.
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.
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.
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.
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.
Failure to vent the boiler properly will result in serious personal
injury or death.
CAUTION
WARNING
WARNING
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.
DANGER
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 6.
CAUTION
WARNING
When drawing combustion air from the outside into the mechanical
room, care must be taken to provide adequate freeze protection.
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 6.
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 6) 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.
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 (22cm
2
/kW) of the total input of
all appliances in the space, but not less than 100 square inches (645cm
2
).
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 Conned or
Unconned Space
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
H. Carbon Monoxide Detectors
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 6.

18
Part 1 - General Safety Information
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.
Ensure that the intake air will not contain any of the contaminants
in Table 6. 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.
WARNING
WARNING
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.
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.
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.)
Products to Avoid Areas Likely to H ave
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 sof-
tening 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 6 - Products and Areas Likely to Have Contaminants
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.
Part 3 - Prepare the Boiler for Installation
J. Removing a Boiler from a Common Vent System
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.
Failure to follow all instructions can result in ue gas spillage and
carbon monoxide emissions, causing severe personal injury or
death.
WARNING
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.
DANGER
Figure 9 - CO Warning Label

19
Part 3 - Prepare the Boiler for Installation
K. Technical Specications
Model TRX085 TRX120 TRX110C TRX150C
Type Boiler Combi
Installation Indoor, Wall Hung, Fully Condensing
Space Heating
Minimum / Maximum Input (Btu/Hr)19,400 / 85,000 13,200 / 120,000 11,200 / 106,000 13,200 / 120,000
Domestic Hot Water
Minimum / Maximum Input (Btu/Hr)1N/A N/A 11,200 / 114,000 13,200 / 150,000
DOE AFUE2 (%) 96 95 95.5 95
Heating Capacity1, 2 (MBH) 79 111 98 111
Net AHRI Rating, Water (MBH)269 97 85 97
Hot Water Capacity
35oF Rise N/A N/A 6.0 7.9
45oF Rise N/A N/A 4.7 6.1
77oF Rise N/A N/A 2.7 3.6
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) 78 84 83 84
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)
W16” 3/64
H43” 5/8
D15” 1/8
Approx. Full Boiler Weight (lbs) 88.2 88.6 91 92.8
Boiler Water Content (Gallons) 1.1 1.2 1.1 1.2
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 55
Pressure Relief Valve 30
DHW Max Pressure N/A N/A 150 150
Control Panel / Main Controller AristonThermo LCD Display / AristonThermo GALEVO2 Control
Connection
Sizes
CH Supply / Return 1” Male Sweat with Adapter
DHW Inlet / Outlet 3/4” Male Sweat with Adapter
Gas Inlet 3/4” Male NPT
Materials Cabinet Painted Steel and Plastic
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, Blocked Condensate Pressure Switch, Condensate Trap, Flue Temperature High Limit Sensor
(210oF), Blocked Vent Pressure Switch
Table 7 - Technical Specications
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 TRX requires a special venting system. Use only the vent materials and methods detailed in these installation instructions.

20
Part 3 - Prepare the Boiler for Installation
(55,3mm)
(150 mm)
(390 mm)
2-3/16”
5-7/8”
15-5/16”
(120 mm)
4-3/4”4-3/4”
(120 mm)
4-5/16”
(110 mm)
(136,5 mm)
5-3/8”
(34,2 mm)
1-3/8”
(400 mm)
15-3/4”
(87,2 mm)
3-7/16”
(87,2 mm)
3-7/16”3-7/16”
(87,6 mm)
3-7/16”
(87,6 mm)
(65mm) (67mm)
2-9/16” (65mm) 2-9/16”2-5/8” (67mm) 2-5/8”
13,1 mm
1/2”
9-7/16”
(239,75 mm)
8-15/16”
(226,65 mm)
(1108,15 mm)
43-5/8”
(745 mm)
29-5/16”
F
A B C D E
Model TRX085 TRX120 Model TRX110C TRX150C
A - Central Heating Supply 1” A - Central Heating Supply 1”
B - Return from Indirect Water Heater 3/4” B - Domestic Hot Water Outlet 3/4”
C - Gas Inlet 3/4” C - Gas Inlet 3/4”
D - Domestic Hot Water Inlet Not Used D - Domestic Hot Water Inlet 3/4”
E - Central Heating Return 1” E - Central Heating Return 1”
F - Pressure Relief Valve 3/4” F - Pressure Relief Valve 3/4”
Table 8 - Boiler Adapter Dimensions
Figure 10 - Boiler Dimensions - NOTE: All Dimensions Are Approximate