NTI TFTN 085-399 User manual

TFTN 085-399
INSTALLATION AND OPERATION MANUAL
Version Date: 2022-09-06
HAZARD SYMBOLS AND DEFINITIONS
Danger Sign: Indicates a hazardous situation which, if not avoided, will result in serious
injury or death.
Warning Sign: Indicates a hazardous situation which, if not avoided, could result in
serious injury or death.
Caution Sign plus Safety Alert Symbol: Indicates a hazardous situation which, if not
avoided, could result in minor or moderate injury.
Caution Sign without Safety Alert Symbol: Indicates a hazardous situation which, if not
avoided, could result in property damage.
Notice Sign: Indicates a hazardous situation which, if not avoided, could result in property
damage.
This Boiler must be installed by a licensed and trained Heating Technician, or the
Warranty is Void. Failure to properly install this unit may result in property damage,
serious injury to occupants, or possibly death.
NTI # 87137

Installation and Operation Manual TFTN 085-199
2
Table of Contents
1.0 INTRODUCTION..............................................................................................................................................................4
1.1 GENERAL INSTALLATION REQUIREMENTS..........................................................................................................................4
1.2 USER RESPONSIBILITIES .................................................................................................................................................4
1.3 INSTALLER RESPONSIBILITIES ..........................................................................................................................................4
1.4 BEFORE OPERATING WITH PROPANE................................................................................................................................5
1.5 BOILER VENT /AIR-INTAKE PIPING...................................................................................................................................5
1.6 DHW TEMPERATURE ADJUSTMENT AND SCALDING ...........................................................................................................5
1.7 IN THE STATE OF MASSACHUSETTS..................................................................................................................................6
2.0 SPECIFICATIONS ...........................................................................................................................................................7
2.1 HIGH ALTITUDE OPERATION ............................................................................................................................................7
2.2 DIMENSIONS ..................................................................................................................................................................8
3.0 BOILER LOCATION.......................................................................................................................................................12
3.1 MINIMUM INSTALLATION CLEARANCES ............................................................................................................................12
3.2 BOILER AREA VENTILATION AIR OPENINGS .....................................................................................................................13
3.3 RESIDENTIAL GARAGE INSTALLATIONS............................................................................................................................13
3.4 WALL MOUNTING INSTRUCTIONS ...................................................................................................................................13
4.0 GENERAL VENTING.....................................................................................................................................................15
4.1 REMOVING AN EXISTING BOILER FROM COMMON VENTING SYSTEM ..................................................................................15
4.2 COMBUSTION AIR INTAKE CONTAMINATION .....................................................................................................................15
4.3 FLAMMABLE SOLVENTS AND PLASTIC PIPING...................................................................................................................16
4.4 BOILER EXHAUST &AIR-INTAKE VENT PIPE CONNECTORS ...............................................................................................17
4.5 VENT PIPE MATERIAL ...................................................................................................................................................18
4.6 EXHAUST AND AIR-INTAKE VENT SIZE &LENGTH.............................................................................................................19
4.7 DIRECT VENT INSTALLATION..........................................................................................................................................19
4.8 POWER VENT /INDOOR COMBUSTION AIR (NON-DIRECT VENT) ........................................................................................25
4.9 GENERAL VENTING RULES AND GUIDELINES ...................................................................................................................25
5.0 VENT TERMINATION CLEARANCES .......................................................................................................................27
6.0 CONDENSATE DRAIN..................................................................................................................................................29
7.0 INSTALLING GAS PIPING ...........................................................................................................................................31
8.0 LIGHTING THE BOILER...............................................................................................................................................33
9.0 GAS VALVE AND BURNER SET-UP.........................................................................................................................35
10.0BOILER AND HEATING SYSTEM PIPING................................................................................................................40
10.1 WATER QUALITY ..........................................................................................................................................................40
10.2 NEAR BOILER PLUMBING...............................................................................................................................................42
10.3 BOILER SYSTEM PLUMBING...........................................................................................................................................44
11.0CASCADE INSTALLATION..........................................................................................................................................54
11.1 GENERAL INSTALLATION INSTRUCTIONS..........................................................................................................................54
11.2 SETUP PROCEDURE .....................................................................................................................................................58
12.0FIELD WIRING ...............................................................................................................................................................62
13.0WIRING SCHEMATICS.................................................................................................................................................68
14.0INSTALLATION CHECKLIST.......................................................................................................................................70
15.0ANNUAL MAINTENANCE AND INSPECTION..........................................................................................................71
16.0DISPLAY MENU GUIDE ...............................................................................................................................................73
16.1 HOME SCREEN ............................................................................................................................................................74
16.2 OPERATING MODE (SCHEDULING)..................................................................................................................................74
16.3 SETUP ........................................................................................................................................................................75
16.3.1 Setup Wizard ...................................................................................... 75
16.3.2 Tech Menu.......................................................................................... 77
16.3.3 User Menu .......................................................................................... 92
16.3.4 Test Mode........................................................................................... 96
16.3.5 Connectivity ........................................................................................ 97
16.3.6 Diagnostics ......................................................................................... 98
16.4 ZONE DETAILS .............................................................................................................................................................99
16.5 BOILER DETAILS...........................................................................................................................................................99
16.6 CASCADE ..................................................................................................................................................................100
16.7 ERRORS....................................................................................................................................................................101
17.0WIFI CONNECTION ....................................................................................................................................................102
18.0TROUBLESHOOTING.................................................................................................................................................105

TFTN 085-199 Installation and Operation Manual
3
Read Before Proceeding
If you do not follow these instructions exactly, a fire or explosion may result causing property
damage, serious injury or death.
FOR YOUR SAFETY, READ BEFORE OPERATING_
A) This boiler does not have a pilot. It is equipped with an ignition device which automatically lights the
burner. Do not try to light the burner by hand.
B) BEFORE OPERATING smell all around the boiler area for gas. Be sure to smell next to the floor
because some gas is heavier than air and will settle on the floor.
WHAT TO DO IF YOU SMELL GAS:
•Do not try to light any boiler.
•Do not touch any electric 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.
C) Use only your hand to turn the gas “shutoff” valve. Never use tools. If the handle will not turn by hand,
don't try to repair it, call a qualified service technician. Force or attempted repair may result in a fire or
explosion.
D) Do not use this boiler if any part has been under water. Immediately call a qualified service technician
to inspect the boiler and to replace any part of the control system and any gas control which has
been under water.
OPERATING INSTRUCTIONS_
1. STOP! Read the safety information above very carefully.
2. Set the thermostat to lowest setting. Turn off all electric power to the boiler.
3. This boiler does not have a pilot. It is equipped with an ignition device which automatically lights the
burner. Do not try to light the burner by hand.
4. Turn the manual gas valve to the OFF position. Remove front access panel.
5. Wait five (5) minutes to clear out any gas. Then smell for gas, including near the floor. If you smell gas,
STOP! Follow “B” in the safety information above. If you don't smell gas, go to the next step.
6. Turn the manual gas valve ON. Wait an additional five (5) minutes smelling for gas.
7. Replace the front access panel.
8. Set thermostat to highest setting. Turn on all electric power to the boiler.
9. Ignition sequence is automatic. Combustion will occur after a brief fan purge.
10. If ignition does not occur, follow the instructions “To Turn Off Gas To Boiler” and call your service
technician or gas supplier.
TO TURN OFF GAS TO THE BOILER_
1. STOP! Read the safety information above very carefully.
2. Turn off all electric power to the boiler.
3. Turn the manual gas valve to the OFF position.
Crystalline Silica –Certain components confined in the combustion chamber may contain this
potential carcinogen. Improper installation, adjustment, alteration, service or maintenance can
cause property damage, serious injury (exposure to hazardous materials) or death. Refer to
Section 15.0 for information on handling instructions and recommended personal protective equipment. Installation and
service must be performed by a qualified installer, service agency or the gas supplier (who must read and follow the supplied
instructions before installing, servicing, or removing this boiler. This boiler contains materials that have been identified as
carcinogenic, or possibly carcinogenic, to humans).
Void Warranty –This Boiler must have water flowing through it whenever the burner is on, or it
will damage the unit and void the warranty. Failure to follow these instructions may result in
serious injury or death.

Installation and Operation Manual TFTN 085-199
4
1.0 INTRODUCTION
1.1 General Installation Requirements
The installation of your NTI TFTN gas-fired boiler must conform to the requirements of this manual, your local authority,
and the National Fuel Gas Code ANSI Z223.1 and or CAN/CGA B149 Installation Codes. Where required by the Authority,
the installation must conform to the standard for “Controls and Safety Devices for Automatically Fired Boilers ANSI/ASME
CSD-1.
This document pertains to the correct installation and operation of NTI boiler models TFTN085, TFTN110, TFTN150 &
TFTN199. The instructions detailed in this document supersede any and all previous instructions provided by NTI, written
or otherwise. Each unit is provided with the following documentation:
1. Installation and Operation Manual (this document)
2. Warranty Terms and Conditions
3. User Information Manual, and
4. Natural Gas to LP Conversion Kit*
* The conversion kit is required to convert the boiler so it will safely operate with Propane Gas.
Read and understand this entire document prior to proceeding with the installation of the TFTN
boiler. Failure to follow the instructions outlined in this document will result in property damage,
serious injury or death.
Energy Saving Feature - 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 any space heating.
▪This boiler is part of a modular or multiple boiler system having a total input of 300,000 BTU/hr or greater.
▪This boiler is equipped with a tankless coil.
1.2 User Responsibilities
This boiler must be installed and serviced by a qualified installer or service technician. This boiler must be serviced and
inspected annually when operating in normal residential applications. Demanding applications or extreme conditions (i.e.,
commercial) may require more frequent service and inspection. As the User/Owner of this equipment, you are responsible
for ensuring the maintenance is performed at the required intervals; see section 15.0 ANNUAL MAINTENANCE AND
INSPECTION.
Failure to have the boiler properly serviced and inspected on a regular basis by a qualified service
technician may result in property damage, serious injury or death.
Failure to keep the Exhaust and Combustion Air Intake clear of ice, snow, and other debris may
result in property damage, serious injury, or death.
1.3 Installer Responsibilities
As the installing technician it is your responsibility to ensure the installation is performed in accordance with this instruction
manual as well as any applicable local or National installation codes. It is also your responsibility to inform the User/Owner
of the “User Responsibilities”. Failure to follow this warning could result in fire, serious injury, or death.

TFTN 085-199 Installation and Operation Manual
5
1.4 Before Operating with Propane
TFTN boilers are factory set to operate with Natural Gas; BEFORE OPERATING WITH PROPANE,
the boiler must be converted using the appropriate Natural Gas to LP Conversion Kit; see below.
Failure to properly convert the unit to safely operate with Propane will cause dangerous burner
operation, resulting in property damage, serious injury or death.
Table 1-1 Natural Gas to LP Conversion Kits
Boiler Model
Natural Gas to LP Conversion Kit
(part no.)
TFTN085-110
87752
TFTN150
87753
TFTN199
87740
TFTN285
87754
Notes:
1. TFTN085-199 models are converted to Propane using a replacement LP-Mixer and Diaphragm insert, which are
provided in the respective Natural Gas to LP Conversion Kit; follow the instructions provided in the kit to
complete the conversion to LP.
2. TFTN285-399 models are converted to Propane by installing an LP-Orifice, which is provided in the respective
Natural Gas to LP Conversion Kit; follow the instructions provided in the kit to complete the conversion to LP.
Liquefied Petroleum (LP) propane gas is heavier than air. Do not install the boiler in a pit or similar
location that will permit heavier than air gas to collect. Check with Local Codes as they may require
boilers fueled with LP gas to be provided with an approved means of removing unburned gases
from the room. Failure to follow these instructions may result in serious injury or death.
1.5 Boiler Vent / Air-Intake Piping
The TFTN is certified as a “Category IV” boiler and requires a “Special Venting System” designed for
pressurized venting. The exhaust gases must be piped directly to the outdoors using the vent
materials and rules outlined in these instructions. Failure to follow these instructions will result in
serious injury or death.
1.6 DHW Temperature Adjustment and Scalding
This boiler, when connected to an Indirect Water Heater (IWH) 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 1-2 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.
Table 1-2 Approximate Scald Time to Temperature Relationship
120°F
More than 5 minutes
125°F
1.5 to 2 minutes
130°F
About 30 seconds
135°F
About 10 seconds
140°F
Less than 5 seconds
145°F
Less than 3 seconds
150°F
About 1.5 seconds
155°F
About 1 second

Installation and Operation Manual TFTN 085-199
6
1.7 In the State of Massachusetts
(a) For all horizontally vented gas fueled equipment installed in every dwelling, building or structure used in whole or
in part for residential purposes, including those owned and operated by the Commonwealth and where the side wall
exhaust vent termination is less than seven (7) feet above finished grade in the area of the venting, including but not
limited to decks and porches, the following requirements shall be satisfied:
1. INSTALLATION OF CARBON MONOXIDE DETECTORS At the time of installation of the side wall
horizontal vented gas fueled equipment, the installing plumber or gas fitter shall observe that a hard-wired
carbon monoxide detector with an alarm and battery back-up is installed on the floor level where the gas
equipment is to be installed and on each additional level of the dwelling, building or structure served by the
equipment. It shall be the responsibility of the property owner to secure the services of qualified licensed
professionals for the installation of hard-wired carbon monoxide detectors.
a. In the event that the side wall horizontally vented gas fueled equipment is installed in a crawl space or an
attic, the hard wired carbon monoxide detector with alarm and battery back-up may be installed on the next
adjacent floor level.
b. In the event that the requirements of this subdivision cannot be met at the time of completion of installation,
the owner shall have a period of 30 days to comply with the above requirements; provided, however, that
during said 30-day period a battery operated carbon monoxide detector with an alarm shall be installed.
2. APPROVED CARBON MONOXIDE DETECTORS Each carbon monoxide detector as required in accordance
with the above provisions shall comply with NFPA 720 and be ANSI/UL 2034 listed and IAS certified.
3. SIGNAGE A metal or plastic identification plate shall be permanently mounted to the exterior of the building
at a minimum height of eight (8) feet above grade directly in line with the exhaust vent terminal for the
horizontally vented gas fueled heating boiler or equipment. The sign shall read, in print size no less than one-
half (1/2) inch in size, “GAS VENT DIRECTLY BELOW. KEEP CLEAR OF ALL OBSTRUCTIONS” (plate
included with boiler).
4. INSPECTION The state or local gas inspector of the side wall horizontally vented gas fueled equipment shall
not approve the installation unless, upon inspection, the inspector observes carbon monoxide detectors and
signage installed in accordance with the provisions of 248 CMR 5.08(2)(a)1 through 4.
(b) EXEMPTIONS: The following equipment is exempt from 248 CMR 5.08(2)(a)1 through 4:
1. The equipment listed in Chapter 10 entitled “Equipment Not Required To Be Vented” in the most current
edition of NFPA 54 as adopted by the Board; and
2. Product Approved side wall horizontally vented gas fueled equipment installed in a room or structure separate
from the dwelling, building or structure used in whole or in part for residential purposes.
(c) MANUFACTURER REQUIREMENTS –GAS EQUIPMENT VENTING SYSTEM PROVIDED: When the
manufacturer of Product Approved side wall horizontally vented gas equipment provides a venting system design
or venting system components with the equipment, the instructions provided by the manufacturer for installation of
the equipment and the venting system shall include:
1. Detailed instructions for installation of the venting system design or the venting system components; and
2. A complete parts list for the venting system design or venting system.
(d) MANUFACTURER REQUIREMENTS –GAS EQUIPMENT VENTING SYSTEM NOT PROVIDED:
When the manufacturer of a Product Approved side wall horizontally vented gas fueled equipment does not provide
the parts for venting the flue gases, but identifies “special venting systems”, the following requirements shall be
satisfied by the manufacturer:
1. The referenced “special venting system” instructions shall be included with the appliance or equipment
installation instructions; and
2. The “special venting system” shall be Product Approved by the Board, and the instructions for that system
shall include a parts list and detailed installation instructions.
(e) A copy of all installation instructions for all Product Approved side wall horizontally vented gas fueled equipment,
all venting instructions, all parts list for venting instructions, and/or all venting design instructions shall remain
with the appliance or equipment at the completion of the installation.

TFTN 085-199 Installation and Operation Manual
7
2.0 SPECIFICATIONS
Table 2-1 Specifications
DESCRIPTION
TFTN085
TFTN110
TFTN150
TFTN199
TFTN285
TFTN340
TFTN399
CSA Input Modulation
[MBH] 1
8.5 - 85
11 - 110
15 - 150
19.9 - 199
28.5 - 285
39.9 - 340
39.9 - 399
Heating Capacity [MBH] 1,2
79
101
138
184
263
324
380
Net AHRI Rating, Water
[MBH] 1,2
69
88
120
160
229
282
330
AFUE [%] 2
96
95
95
95
95
95.4
95.4
Water Connections, NPT
[in.]
1-1/4 (M)
1-1/4 (M)
1-1/4 (M)
1-1/4 (M)
1-1/4 (M)
1-1/2 (M)
1-1/2 (M)
Gas Connection, NPT [in.]
¾ (M)
¾ (M)
¾ (M)
¾ (M)
¾ (M)
¾ (M)
¾ (M)
Vent/Air-inlet Pipe Diameter
[in.] 3
2 or 3
2 or 3
2 or 3
3
3
4
4
Cabinet Height [in.]
34-1/8
34-1/8
34-1/8
34-1/8
34-1/8
36-1/2
36-1/2
Cabinet Width [in.]
19-7/8
19-7/8
19-7/8
19-7/8
21-3/8
25-1/4
25-1/4
Cabinet Depth [in.]
17-1/4
17-1/4
18-3/4
18-3/4
18-3/8
18-7/8
21-1/4
Approx. Boiler Weight
with Water [lbs]
107
107
122
140
180
250
250
Approx. Boiler Water
Content [Gallons]
1.4
1.4
2.0
2.8
4.9
7.1
6.4
Electrical Rating
120V / 1Ph / 60Hz / less than 12A
Notes:
1. Listed Input and Output ratings are at minimum vent lengths at an altitude of 0-2000ft. Numbers will be lower with
longer venting and/or altitudes greater then 2000ft.
2. Ratings based on standard test procedures prescribed by the U.S. Department of Energy; certified by AHRI.
Efficiency listed for models TFTN340 & TFTN399 represents Thermal Efficiency (AFUE is not applicable).
3. TFTN units require a special venting system, use only vent materials and methods detailed in these instructions.
2.1 High Altitude Operation
The TFTN is designed to operate at its maximum listed capacity in installations located at 0-2000ft above Sea Level. Since
the density of air decreases as elevation increases, maximum specified capacity should be de-rated for elevations above
2000 ft [610 m] in accordance with Table 2-2.
Table 2-2 De-rate % for High Altitudes
Elevations
2001 ft.
3000 ft.
4000 ft.
4500 ft.
5000 ft.
In Canada 1
de-rate by 10%
de-rate by 10%
de-rate by 10%
de-rate by 10%
de-rate % may vary
In USA 2
-
de-rate by 12%
de-rate by 16%
de-rate by 18%
de-rate by 20%
Notes:
1Canada: Altitudes between 2000-4500 ft., de-rate by 10%. Consult local authorities for de-rating capacities for
altitudes above 4500 ft.
2USA: De-rate capacity by 4% for every 1000 ft [305 m], if altitude is above 2000 ft.
Combustion –At elevations above 2000 feet, the combustion of the boiler must be checked with
a calibrated combustion analyzer to ensure safe and reliable operation. It is the Installers
responsibility to check the combustion and to adjust the combustion in accordance with section
9.0 GAS VALVE AND BURNER SET-UP. Failure to follow these instructions may result in property
damage, serious injury, or death.

Installation and Operation Manual TFTN 085-199
8
2.2 Dimensions
Figure 2-1 Boiler Dimension (TFTN085-110)
Connection/Description
Size
Connection/Description
Size
A –Central Heating Supply
1-1/4 in.
C –Gas Inlet
3/4 in.
B –Central Heating Return
1-1/4 in.
D –Condensate Drain
*
* Condensate trap is factory installed inside the boiler, connect drain to drain tube supplied with the boiler.
C
A
B
D
A
B
C
D
A
B
B
A

TFTN 085-199 Installation and Operation Manual
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Figure 2-2 Boiler Dimension (TFTN150-199)
Connection/Description
Size
Connection/Description
Size
A –Central Heating Supply
1-1/4 in.
C –Gas Inlet
3/4 in.
B –Central Heating Return
1-1/4 in.
D –Condensate Drain
*
* Condensate trap is factory installed inside the boiler, connect drain to drain tube supplied with the boiler.
C
A
B
D
A
B
C
D
A
B
B
A

Installation and Operation Manual TFTN 085-199
10
Figure 2-3 Boiler Dimension (TFTN285)
Connection/Description
Size
Connection/Description
Size
A –Central Heating Supply
1-1/4 in.
C –Gas Inlet
3/4 in.
B –Central Heating Return
1-1/4 in.
D –Condensate Drain
*
* The condensate trap is shipped separately with the boiler, and must be field installed; see section 6.0.
C
B
A
D
B
A
C
D
B
A
A
B
C
C

TFTN 085-199 Installation and Operation Manual
11
Figure 2-4 Boiler Dimension (TFTN340-399)
Connection/Description
Size
Connection/Description
Size
A –Central Heating Supply
1-1/2 in.
C –Gas Inlet
3/4 in.
B –Central Heating Return
1-1/2 in.
D –Condensate Drain
*
* The condensate trap is shipped separately with the boiler, and must be field installed; see section 6.0.
C
A
B
D
A
B
C
D
A
B
B
A
C
C

Installation and Operation Manual TFTN 085-199
12
3.0 BOILER LOCATION
In all cases, the TFTN boiler must be installed indoors in a dry location where the ambient temperature must be maintained
above freezing and below 100F [38C]. All boiler components must be protected from dripping, spraying water, or rain
during operation and servicing. Consider the proximity of system piping, gas and electrical supply, condensate disposal drain,
and proximity to vent termination when determining the best boiler location.
Water or flood damaged components must be replaced immediately with new factory-approved
components as failure to do so may result in fire, serious injury, or death.
3.1 Minimum Installation Clearances
Figure 3-1 Minimum Clearance for Installation and Service
Dimension
Description
Clearance
Minimum
Recommended
A
Top
12 in.
24 in.
B
Sides
2 in.
12 in.
C1
Front
18 in.
36 in.
D
Bottom
14 in.
24 in.
Not Illustrated
Back
0
0
Flue & Water Pipes
1 in.
1 in.
Notes:
1Front clearance can be as little as 6” if surface is removable allowing a minimum of 18” clearance.

TFTN 085-199 Installation and Operation Manual
13
3.2 Boiler Area Ventilation Air Openings
Direct Vent –If boiler area clearances are less than the recommended clearances specified in Figure 3-1, the boiler area
must be ventilated (Exception: if the boiler area/room has a volume of 150 ft3or greater, ventilation of the boiler 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 ventilation opening must be located within 6” of the floor while the upper opening must be
located 6” from the top of the space.
If the "Boiler Area" does not meet the recommended clearances listed in Figure 3-1, and if the
boiler area has a volume less than 150 ft3, it is considered a Closet or Alcove. PVC vent pipe and
fittings shall not be used within the closet or alcove; only approved CPVC, Polypropylene or
Stainless-Steel vent pipe and fittings can be used. See Table 4-3 for a list of approved materials.
Under all circumstances, the minimum clearances listed in Figure 3-1 must be provided.
Power Vent / Indoor Combustion Air –When using Indoor Combustion Air in lieu of Direct Vent air intake piping, provisions
for combustion and ventilation air, in accordance with section “Air for Combustion and Ventilation,” of the National Fuel
Gas Code, ANSI Z223.1/NFPA 54 (U.S.), or Clause 8.2, 8.3 or 8.4 of Natural Gas and Propane Installation Code, CAN/CSA
B149.1 (Canada), or applicable provisions of the local building codes, must be adhered to.
Closet Installations –For closet installations it is necessary to provide two ventilation air openings, each with a minimum
area equal to 1 in2per 1000 Btu/hr, but not less than 100 in2, and within 6” of the top and bottom of the closet door.
See Figure 3-1 for minimum clearances.
Alcove Installations –Alcove installations have the same minimum clearances as closet installations, except the front must
be completely open to the room at a distance no greater than 18” [457 mm] from the front of the boiler and the room
is 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. See Figure 3-1 for minimum clearances.
Closet/alcove installations in US and Canada require approved CPVC, Polypropylene or Stainless-
Steel vent and air intake pipe and fittings (see Table 4-3); PVC is not permitted. Failure to follow
these instructions may result in damage or serious injury.
3.3 Residential Garage Installations
When installed in a residential garage, mount the boiler a minimum of 18” [457 mm] above the floor. Locate or protect the
boiler so it cannot be damaged by a moving vehicle. Check with your local authorities for other possible regulations
pertaining to the installation of a boiler in a garage.
3.4 Wall Mounting Instructions
The TFTN is provided with integrated wall mounting brackets. Refer to Figure 3-2 for instructions and illustrations on wall
mounting.

Installation and Operation Manual TFTN 085-199
14
Figure 3-2 Wall Mounting Instructions
Locate the wall mounting brackets and
hardware furnished with the boiler.
(A)
(B)
(C)
(D)
(E)
(F)
(F)
A –(4) Fischer plug anchor, p/n 86885
B –(4) 5/16” washer, p/n 86886
C –(4) 5/16” x 2-1/2” lag bolt, p/n 86884
D –(3) 1/4” machine screw [TFTN085-199]
–(4) 1/4” machine screw [TFTN285-399]
E –(1) Upper wall mount bracket, p/n 86938
F –(1) Lower wall mount bracket [TFTN085-
199], p/n 86937
–(1) Lower wall mount bracket set
[TFTN285-399], p/n 86460
Secure the upper wall mount bracket to the wall
using the supplied lag bolts and washers. Ensure
the bracket is level. Use the Fischer plug anchors
if a stud is not available.
With the help of an assistant, hang the boiler on the upper
wall mount bracket. Align the openings in the back of the
boiler with the hooks of the wall mount bracket. Make
sure that it is securely hooked and that the wall mount
bracket remains securely fastened to the wall.
Loosely install the lower wall mount bracket(s) to the
bottom of the boiler, and then fasten the bracket to
the wall with field supplied hardware. Tighten the
bracket to the bottom of the boiler once the boiler is
plumb.
When hitting a stud
When using Fischer
plug anchors
Reverse view
Two people are required to lift the
boiler into place. Failure to follow
these instructions may result in
property damage or personal injury

TFTN 085-199 Installation and Operation Manual
15
4.0 GENERAL VENTING
The TFTN is certified as a “Category IV” boiler requiring a “Special Venting System” designed for pressurized venting. The
Exhaust must be piped to the outdoors, using the vent materials and rules outlined in this section. Under no conditions may
this unit vent gases into a masonry chimney, unless it is vacant, and utilizes the approved venting material and rules
described in this section.
The venting system shall be installed in accordance with the instructions contained within this
document and, if applicable, the venting system manufacturer’s instructions. Failure to properly
install the venting system may result in flue gas spillage or recycling, causing property damage,
personal injury, or death.
Exhaust and Air Intake are to be piped separately. The TFTN cannot share a common vent or air
intake with multiple boilers unless the common venting system has been certified by NTI (Contact
NTI for details). Failure to comply will result in serious injury or death.
4.1 Removing an Existing Boiler from Common Venting System
Do not install the TFTN into a common venting system with any other boiler. Failure to comply
with this warning will cause flue gas spillage and leech carbon monoxide emissions into the
surrounding air resulting in serious injury or death.
When an existing boiler is removed from a common venting system, the common venting system
is likely to be too large for proper venting of the remaining boilers connected to it. Instructions
have been provided on how to remove the existing boiler and how to resize the remaining venting
system. Failure to follow these instructions may result in property damage, serious injury or death.
Upon removal of an existing boiler, the following steps shall be followed for each boiler remaining in the common venting
system; prior to commencing this procedure, shutdown all boilers remaining in the common venting system.
Steps to Removing an Existing Boiler:
1. Seal any unused openings in the common venting system.
2. Visually inspect the venting system for proper size and horizontal pitch. Verify that there is no blockage, restriction,
leakage, corrosion, or other deficiencies which could cause an unsafe condition.
3. Insofar as is practical, close fireplace dampers, all building doors and windows and all doors between the space in which
the boilers remaining connected to the common venting system are located and other spaces of the building. Turn on
clothes dryers and any boiler not connected to the common venting system. Turn on any exhaust fans, such as range
hoods and bathroom exhausts, so they will operate at maximum speed. Do not operate a summer exhaust fan.
4. Place in operation the boiler being inspected. Follow the applicable lighting instructions. Adjust thermostat so boiler
will operate continuously.
5. Test for spillage at the draft hood relief opening after 5 minutes of main burner operation. Use the flame of a match or
candle, or smoke from a cigarette, cigar, or pipe.
6. After it has been determined that each boiler remaining connected to the common venting system properly vents when
tested as outlined above, return doors, windows, exhaust fans, fireplace dampers and any other gas burning boiler to
their previous condition of use.
7. Any improper operation of the common venting system should be corrected so the installation conforms to the National
Fuel Gas Code, ANSI Z223.1/NFPA 54 and/or CAN/CSA B149.1, Natural Gas and Propane Installation Code. When resizing
any portion of the common venting system, the common venting system should be resized to approach the minimum
size as determined using the appropriate tables in Part 11 of the National Fuel Gas Code, ANSI Z223.1/NFPA 54 and/or
CAN/CSA B149.1, Natural Gas and Propane Installation Code.
4.2 Combustion Air Intake Contamination
Be careful not to locate the air intake termination in an area where contaminants can be drawn in and used for combustion.
Combustion air containing dust, debris or air-borne contaminants will drastically increase the required maintenance and
may cause a corrosive reaction in the Heat Exchanger which could result in premature failure, fire, serious injury, or death.
See Table 4-1 for a list of areas to avoid when terminating air intake piping:

Installation and Operation Manual TFTN 085-199
16
Table 4-1 Corrosive Products and Contaminant Sources
Products to Avoid
Contaminated Sources to Avoid
Antistatic fabric softeners, bleaches, detergents, cleaners
Laundry facilities
Perchloroethylene (PCE), hydrocarbon-based cleaners
Dry cleaning facilities
Chemical fertilizer, herbicides/pesticides, dust, methane gas
Farms or areas with livestock and manure
Paint or varnish removers, cements or glues, sawdust
Wood working or furniture refinishing shops
Water chlorination chemicals (chloride, fluoride)
Swimming pools, hot tubs
Solvents, cutting oils, fiberglass, cleaning solvents
Auto body or metal working shops
Refrigerant charge with CFC or HCFC
Refrigerant repair shops
Permanent wave solutions
Beauty shops
Fixer, hydrochloric acid (muriatic acid), bromide, iodine
Photo labs, chemical / plastics processing plants
Cement powder, crack fill dust, cellulose, fiber-based insulation
Concrete plant or construction site
Do not store or use gasoline or other flammable vapors and liquids in the vicinity of this or any
other boiler. Failure to follow instructions may result in serious injury or death.
It is BEST PRACTICE to pipe the combustion air intake directly to the outdoors (Direct Vent
installation) to avoid contamination often contained in indoor air.
4.3 Flammable Solvents and Plastic Piping
Due to the extremely flammable characteristics of most glues, cements, solvents, and primers used in the process of joining
plastic vent and air intake pipe, explosive solvent vapors must be evacuated from the vent and air intake prior to start-up.
Avoid using excess cement or primer that may lead to pooling inside the pipe assembly. Freshly assembled piping assembly
should be allowed to cure for a minimum of 8 hours before applying power to the gas fired boiler. Refer to Mandatory Pre-
commissioning Procedure for Plastic Venting in this section.
Flammable Cements and Primers –It is the installers’ responsibility to familiarize themselves with
the hazards associated with explosive solvents and to take all precautions to reduce these risks.
Failure to follow these instructions can cause explosions, property damage, injury or death.
Mandatory Pre-commissioning Procedure for Plastic Venting (PVC or CPVC)
Do not apply power to the boiler prior to Step 4 in the Mandatory Pre-commissioning Procedure
for Plastic Venting.
1) Working with the power turned off to the boiler, completely install the vent and air intake system, securely cementing
joints together. If possible, allow primers/cements to cure for 8 hours before firing the burner. If curing time is less than
8 hours, proceed with Steps 2 through 6.
2) Maintain the boiler gas supply shut-off valve in the off position.
3) Remove the cable from the Spark Ignition Transformer.
Spark Ignition Circuit - Maintain a safe distance (2 inches minimum) from the spark ignition
circuit to avoid injury from electrical shock.
4) Turn power on to the boiler and apply a heat demand.
5) Allow for 3 complete trials for ignition, consisting of pre and post purge of the combustion blower, until an ignition
lockout occurs. Repeat the process two more times (i.e., 9 complete ignition sequences in total).
6) Turn power off and reconnect the cable to the Spark Ignition Transformer.

TFTN 085-199 Installation and Operation Manual
17
4.4 Boiler Exhaust & Air-Intake Vent Pipe Connectors
The TFTN employs universal exhaust and air-intake connectors that accept PVC/CPVC or Polypropylene (or in the case of the
TFTN340-399, Stainless-Steel) special gas vent; see Figure 4-1.
Note: When inserting the vent pipe into the connector, verify that the gasket is lubricated and properly seated, and that
pipe ends are cut square and beveled at approximately 1/8 in. to avoid damaging or dislodging the gasket during installation.
Gasket Sealing –Failure to properly prepare the vent pipe and gasket before installation may cause
gasket seal failure resulting in property damage, serious injury or death.
PVC Exhaust Piping –When venting the exhaust with PVC, use the supplied CPVC Transition Pipe provided with the boiler;
insert the CPVC pipe into the exhaust connector and cement the other end to the PVC exhaust venting using a field
supplied PVC or CPVC coupling. See Figure 4-1.
DO NOT insert PVC pipe directly into the boiler exhaust connector, as it can deform from the
clamping force of the gear clamp. Failure to follow these instructions may result in gasket failure
and/or the dislodging of the exhaust vent from the connector, resulting in property damage, serious
injury or death.
Polypropylene Piping –TFTN085-285 exhaust and air-intake connectors accept approved 3 in. Polypropylene special gas vent
with 80 mm outside diameter. TFTN340-399 exhaust and ai- intake connectors accept approved 4 in. Polypropylene
special gas vent with 100 mm outside diameter.
Note: 4 in. Polypropylene with 110 mm outside diameter must be adapted to fit the boiler vent pipe connector using the
applicable field supplied adapter; see Table 4.2
Stainless-Steel Piping –TFTN340-399 exhaust and air-intake connectors accept approved 4 in. Stainless-Steel special gas vent
with a 4 in. outside diameter. TFTN085-285 exhaust and air-intake connectors do not accept Stainless-Steel vent; to vent
these models with Stainless-Steel, use the applicable field supplied adapter –See Table 4.2.
Failure to use the appropriate exhaust vent adaptor for the type of venting being used will lead to
flue gas leakage possibly resulting in property damage, Carbon Monoxide poisoning or death.
Follow the Special Gas Venting manufacturer’s assembly instructions. DO NOT connect
Polypropylene vent pipes & fittings, or Stainless-Steel vent pipes & fittings, together unless they
are of the same brand and type. Failure to follow these instructions may lead to flue gas leakage
possibly resulting in property damage, Carbon Monoxide poisoning or death.
Table 4-2 Appliance Adapters for Polypropylene and Stainless-Steel Venting
Vent Material
Venting Brand
Adapter Part No.
TFTN085-285
TFTN340-399
Polypropylene
DuraVent (PolyPro®)
NA1
NA2
Centrotherm (InnoFlue®)
ISAA0404
Z-Flex (Z-Dens®)
2ZDCPVCG4
Stainless Steel
DuraVent (FasNSeal®)
810005378
NA2
Z-Flex (Z-Vent®)
2SVSTTA03
Notes:
1TFTN085-285 exhaust and air-intake connectors are designed to directly accept 3 in. Polypropylene Special Gas Vent.
2TFTN340-399 exhaust and air-intake connectors are designed to directly accept 4 in. DuraVent PolyPro® Polypropylene
Special Gas Vent, as well as 4 in. DuraVent FasNSeal and Z-Flex Z-Vent® Stainless Steel Special Gas Vent.
Exhaust vent piping must be supported to reduce strain on piping joints. Failure to follow these
instructions may result in result in damage, serious injury or death.
In Canada, the first 3 ft (915 mm) of exhaust vent piping must be readily accessible for inspection.

Installation and Operation Manual TFTN 085-199
18
Figure 4-1 Exhaust & Air-Intake Connections
4.5 Vent Pipe Material
Table 4-3 Acceptable Exhaust and Air-Intake Vent Pipe Material
Items 1
Materials 2, 3
Venting System Standards
Exhaust and Air-Intake materials
installed on gas fired appliances in
CAN/US must meet the specifications
provided in this Table. Failure to
comply could result in fire, serious
injury or death.
United States
Canada
Vent Pipe
and
Fittings
PVC –DWV
Schedule 40/80
UL-1738 or
ANSI/ASTM D2665
ULC S636
PVC Schedule 40/80
UL-1738 or
ANSI/ASTM D1785
CPVC Schedule
40/80
UL-1738 or
ANSI/ASTM F441
Stainless-Steel (SS)
UL-1738
Polypropylene (PP)
UL-1738 or ULC S636
Pipe
Cement
PVC
ANSI/ASTM D2564
CPVC
ANSI/ASTM F493
Primers
PVC / CPVC
ANSI/ASTM F656
Notes:
1Refer to Tables 4-4 and 4-5 for Allowable Vent Size & Length.
2PVC venting (exhaust and air intake) is not permitted within the Closet/alcove of a Closet/alcove installation.
3The Air Intake does not require high temperature pipe material; ABS and PVC Foam Core piping is acceptable. Check
applicable local codes for acceptable materials.
The use of cellular core PVC (ASTM F891), cellular core CPVC, or Radel® (polyphenolsulfone) in the
exhaust venting system is prohibited. Failure to follow these instructions may result in property
damage, personal injury, or death.
Covering non-metallic exhaust vent pipe and fittings with thermal insulation is prohibited. Failure
to follow these instructions may result in property damage, personal injury or death.
TFTN085-285
TFTN340-399
Air-Intake
Exhaust
Air-Intake
Exhaust
CPVC
Transition
Pipe*
CPVC
Transition
Pipe*
* CPVC Transition Pipe (included) is
mandatory when venting with PVC.

TFTN 085-199 Installation and Operation Manual
19
The use of double-wall vent or insulated material for the combustion air intake pipe is
recommended in cold climates to prevent the condensation of airborne moisture on the incoming
combustion air pipe.
4.6 Exhaust and Air-Intake Vent Size & Length
TFTN085-285 models are equipped with 3 in. diameter exhaust and air intake collars and can be vented in 3 in. diameter
pipe up to a maximum of 150 ft. equivalent for each the exhaust and the air-intake vent. Alternatively, TFTN085-199
models (ONLY) can be vented with 2 in. diameter pipe up to a maximum of 100 ft. equivalent for each the exhaust and
air-intake vent.
NOTE: a reducing coupling MUST BE USED when transitioning from 3 in. to 2 in. vent pipe. DO NOT use reducing bushings.
TFTN340-399 models are equipped with 4 in. diameter exhaust and air intake collars and can be vented in 4 in. diameter
pipe up to a maximum of 150 ft. equivalent for each the exhaust and the air-intake vent.
Use Tables 4-4 and 4-5 to determine the maximum pipe length and number of fittings that can be used to make up the
exhaust and air-intake venting.
Table 4-4 Allowable Vent Size & Length
Table 4-5 Equivalent Length of Fittings
Models
Pipe Size
(in.)
Exhaust Vent
Length (ft.) *
Air-Intake Vent
Length (ft.) *
Fitting
Equivalent
Length (ft.)
TFTN085-199
2
6 - 100
0 - 100
90 Degree Elbow
5
TFTN285
2
0 - 6
NA
45 Degree Elbow
3
TFTN085-285
3
6 - 150
0 - 150
Coupling
0
TFTN340-399
3
0 - 6
NA
Concentric Vent
3
TFTN340-399
4
6 - 150
0 - 150
Each foot of vent pipe
1
* Lengths represent the allowable equivalent pipe length; see Table
4-5 for a list of equivalent lengths of fittings.
4.7 Direct Vent Installation
When installed as a Direct Vent boiler the combustion air intake must also be piped directly to the outdoors using the
methods described in this section and in accordance with the National Fuel Gas Code, ANSI Z223.1 (U.S.) or CSA B149.1
(Canada) and local requirements.
Termination Options
The venting system of the TFTN may be terminated using field supplied piping to construct a “Two-Pipe” termination; see
Figures 4-2(a)(e)(h), 4-3(a), 4-4(a)(d), 4-5, 4-6 and 4-7. Alternatively, the venting may be terminated using a factory kit
selected from Table 4-7; see Figures 4-2(b)(c)(d)(f)(g), 4-3(b)(c)(d) and 4-4(b)(c).
Sidewall Termination - Due to potential moisture loading (build-up) along the exterior wall,
sidewall venting may not be the preferred venting option. Refer to Figures 4-2(e)(f)(g)(h) and 4-
4(a)(b)(c)(d) for roof top venting options.
When sidewall venting, it is recommended to reduce the diameter of the exhaust vent at the
termination, to increase exhaust gas velocity, further directing it away from the building. The final
6 ft. of exhaust vent can be reduced to a diameter of 2 in. for models TFTN085-285, and 3 in. for
models TFTN340-399.
The vent for this appliance shall not terminate over public walkways; or near soffit vents or crawl
space vents or other area where condensate of vapor could create a nuisance or hazard or cause
property damage; or where condensate or vapor could cause damage or could be detrimental to
the operation of regulators, relief valves, or other equipment.
Extra precaution must be taken to adequately support the weight of the Exhaust/Air Intake piping
in applications using roof-top terminations. Failure to follow these instructions may result in
venting or boiler component failure resulting in flue gas spillage leading to property damage,
serious injury or death.

Installation and Operation Manual TFTN 085-199
20
Optional Termination Kits
Kits certified with the TFTN are listed in Table 4-7 and available from the manufacturers listed in Table 4-6. Kits with an NTI
part number listed in Table 4-7, are available directly from NTI.
Table 4-6 Optional Termination Kit OEMs
Venting Brand
Vent Manufacturer
Contact Information
System 636®
IPEX Inc.
www.ipexinc.com
PolyPro®
DuraVent
www.duravent.com
InnoFlue®
Centrotherm Eco Systems
www.centrotherm.us.com
Z-DENS®
Z-Flex Venting Systems
www.z-flex.com
Table 4-7 Optional Vent Termination Kits
Description
Vent
Size
Supplier P/N
Figure
Vent Material
Compatibility
Vent Option
Roof
Wall
IPEX Low Profile (Wall)7
2”
196984 (NTI P/N 85062)
4-2(b), 4-3(c)
PVC/CPVC7
-

3”
196985 (NTI P/N 84357)
4”
196986 (NTI P/N 84358)
IPEX Concentric
(Wall/Roof)5,6,7,8
2”
196125
4-2(c)(f), 4-3(b),
4-4(b)
PVC/CPVC7


3”
196116 (NTI P/N 84634), 197117
4”
196021 (NTI P/N 84355), 197021
PolyPro® Twin Pipe (Wall)
4”
4PPS-HTPL
PolyPro®
Polypropylene
-

PolyPro® Concentric (Wall)
2-4”
2PPS-HK, 3PPS-HK,
4PPS-HK
4-2(d), 4-3(d)
-

PolyPro® Concentric (Roof)
2-4”
2PPS-VK, 3PPS-VK,
4PPS-VK
4-2(g), 4-4(c)

-
InnoFlue® Flush Mount
(Wall)
2-3”
ISLPT0202, ISLPT0303
InnoFlue®
Polypropylene
-

InnoFlue® Concentric (Wall)9
2-4”
(ICWT242 & ICTC0224),
(ICWT352 & ICTC0335),
(ICWTS462 & ICTC0446)
4-2(d), 4-3(d)
InnoFlue® Concentric (Roof)9
2-4”
(ICRT2439 & ICTC0224),
(ICRT3539 & ICTC0335),
(ICRT4679 & ICTC0446)
4-2(g), 4-4(c)

-
Z-DENS® Horizontal Kit Low
Profile (Wall)
3-4”
2ZDHKLP3, 2ZDHKLP4
Z-DENS®
Polypropylene
-

Z-DENS® Concentric (Wall)
2-4”
2ZDHK2, 2ZDHK3, 2ZDHK4
4-2(d), 4-3(d)
Z-DENS® Concentric (Roof)
2-4”
2ZDVK2, 2ZDVK3, 2ZDVK4
4-2(g), 4-4(c)

-
Z-VENT® Termination Hood
–Exhaust (Wall)
3-4”
2SVSHTX03, 2SVSHTX04,
2SVSHTX05
Z-VENT®
Stainless Steel
-

Notes:
1Instructions included with termination kits contain detailed assembly and installation instructions.
2Concentric kits can be shortened to fit the requirements of the installation; see instructions included with the kit for
more details.
32 in. Vent Termination Kits may only be used with models TFTN085-285.
43 in. Vent Termination Kits may only be used with models TFTN085-399.
54 in. Vent Termination Kits may only be used with models TFTN340-399.
PVC In Canada - Authorities in some jurisdictions may not allow the use of any PVC venting
materials with condensing boilers; check with the local safety inspector to verify compliance prior
to installing a PVC Concentric Vent Kit with a TFTN boiler.