NTI GF150 User manual

®
CUS
Keep this manual near this appliance for future reference
whenever maintenance or service is required.
GF150 Installation Manual
Combination gas-fired, condensing
combi boiler and space heating fan coil
WARNING
This appliance (GF150) is a combination gas-fired, condensing, combi boiler and space heating
fan coil. The boiler is a CSA-certified product in its own right and, as such, must be installed
according to its installation and operation manuals (supplied).
This manual provides installation instructions for the GF150, but defers to the boiler’s manual(s)
where appropriate.Throughout, in any conflict between instructions from this manual and those
from the boiler’s, the latter are assumed to be correct (unless otherwise noted). When reading
the boiler manuals, only sections pertaining to the TRX150C model may apply.
If the information in these instructions is not followed exactly, a fire or explosion may result,
causing property damage, personal injury or death.
Do not store or use gasoline or other flammable 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 fire department.
Installation and service must be performed by a qualified installer, service agency or the gas supplier.
The installation must conform with local codes or, in the absence of local codes, the National Fuel
Gas Code, ANSIZ223.1/NFPA 54 and/or CSA B149.1, Natural Gas and Propane Installation Code.
When applicable, the installation must conform with the Manufactured Home Construction and
Safety Standard, Title 24 CFR, Part 3280 and/or CAN/CSA Z240 MH Series, Mobile Homes.
M C V
D
C
B
A
D
C
B
A
4
1
4 3
2
1
BY TERM LAWS WE RESERVE THE PROPERTY OF THIS DRAWING WITH PROHIBITION OF USE AND REPRODUCTION
Precision level for dimentions witho ut tolerance indications has to be:
Document code
Drawing format
Designer
Date
Scale
Material
Treatment
Finishing
Description
Code
2
3
RL
Modification descripti on
A4
Designer Date
Code
ECN first creation
Revision
EN 22768-ISO 2768
Production Plant
30 Stonegate Drive,
Saint John, NB E2H 0A4
xx.xx.20xx
1:1
F
= 0 = 0 = 0
K L H
XX
Conformity requirements see the document named "R&D.TB005Tt-xx"
D. Grimmer
NSF/ANSI 372

2
1. Important Information 3
1.1 Safety Information 3
2. About the Appliance 5
2.1 Items Included 5
2.2 Specications 6
2.3 Display 7
2.4 Components 8
2.5 Dimensions 9
2.6 Rating Plate 10
3. Installing the Appliance 11
3.1 Choosing an Installation Location 11
3.2 Installation Clearances 12
3.3 Ducting the Appliance 12
3.4 Connecting the Condensate Drain 14
3.5 Connecting the Water Piping 16
3.6 Connecting a CH System 21
3.7 Venting the Appliance 24
3.8 Connecting the Gas Supply 24
3.9 Connecting the Electrical 26
3.10 Conguring the Appliance 28
4. Appendices 37
4.1 Blower Performance 37
4.2 Wiring Diagram 38
4.3 Ladder Diagram 39
4.4 Component Diagrams and Parts Lists 40
4.5 Installation Checklist 42
4.6 Troubleshooting 43
Contents

1.1 Safety Information
The following safety symbols are used in this manual.
Read and follow all safety instructions in this manual
precisely to avoid unsafe operating conditions, re,
explosion, property damage, personal injury, or death.
DANGER
Indicates an imminently hazardous situation
which, if not avoided, could result in severe
injury or death.
WARNING
Indicates a potentially hazardous situation
which, if not avoided, could result in injury or
death.
If you smell gas:
●Do not try to light any appliance.
●Do not touch any electrical switches or use
landline phones.
●From a neighbor’s phone, call your gas provider
and follow their instructions.
●If you cannot reach your gas provider, call the re
department.
Do not use or store ammable products, such as
gasoline, solvents, or adhesives in the same room or
area as the appliance.
●The appliance has a main burner ame that can
turn on at any time and can ignite ammable
vapors. Vapors from ammable liquids can explode
and catch re, causing death or severe burns.
●Vapors cannot be seen and may be heavier than
air. They can travel long distances along the
ground and can be carried from other rooms to
the appliance's main burner ame by air current.
●Keep all ammable products far away from the
appliance and store them in approved containers.
Keep the containers closed tightly and out of the
reach of children and pets.
DANGER
3
This appliance (GF150) is a combination gas-red,
condensing combi boiler and space heating fan coil.
The boiler is a CSA-certied product in its own right
and, as such, must be installed according to its
installation and operation manuals (supplied).
This manual provides installation instructions for
the GF150, but defers to the boiler manuals where
appropriate. Throughout, in any conict between
instructions from this manual and those from the
boiler’s, the latter are assumed to be correct.
When reading the boiler manuals, only those sections
pertaining to the TRX150C model may apply.
As part of the GF150’s manufacturing process, certain
portions of the boiler's installation have been com-
pleted. As such, some sections of this manual
dier signicantly from the corresponding
instructions in the boiler manuals.
In these sections, it is intended that the installer
follow the specic instructions as described for the
GF150, while following the general instructions in
the boiler manuals.
Installation and service must be performed by a
qualied installer, service agency, or the gas supplier.
Failure to follow these and other included
instructions exactly could result in a re or explosion,
causing property damage, personal injury, or death.
1. Important Information CAUTION
Indicates a potentially hazardous situation
which, if not avoided, could result in property
damage.

●Do not store or use gasoline or other ammable
liquids near this appliance.
Doing so may result in re or explosion.
●Do not place combustibles, such as newspapers or
laundry, near the appliance or venting system.
Doing so may result in a re.
●Do not place or use hair sprays, spray paints, or
any other compressed gases near the appliance or
venting system, including the vent termination.
Doing so may result in re or explosion.
●Do not remove the front cover unless the power to
the appliance is turned o or disconnected.
Failure to do so may result in electric shock.
●Do not operate the appliance with the front cover
opened.
Doing so may result in re or carbon monoxide
(CO) poisoning, which may result in property
damage, personal injury, or death.
●Do not operate this appliance without proper
venting.
Doing so may result in re or carbon monoxide
(CO) poisoning, which may result in property
damage, personal injury, or death.
●Do not touch the internal components of the
appliance with wet hands.
Doing so may result in electric shock.
●Do not turn on the appliance unless the water and
gas supplies are fully opened.
Doing so may damage the appliance.
●Do not turn on the water if the cold water supply
shut-o valve is closed.
Doing so may damage the appliance.
●Do not use this appliance for anything other than
its intended purpose, as described in this manual.
●When servicing the controls, label all wires prior to
disconnecting them.
Failure to do so may result in wiring errors, which
can lead to improper or dangerous operation.
Verify proper operation after servicing.
●Do not use unapproved replacement or accessory
parts.
Doing so may result in improper or dangerous
operation and will void the manufacturer’s
warranty.
●Do not place anything in or around the vent
terminals, such as a clothes line, that could
obstruct the air ow in or out of the appliance.
●This appliance has been approved for use in the
USA and Canada only. Using the appliance in
any other country will void the manufacturer’s
warranty.
WARNING CAUTION
4

Kit Box, including: Item Part No. Qty
2”CPVC Pipe, 5.5” Long 86586 1
DHW Pressure Relief Valve (125 psi) +
Brass Tee
83983
87438 1 + 1
CH Pressure Relief Valve (30 psi) +
Connection Tube (w/ gasket)
13701
+
87360
(85167)
1 + 1 (1)
LP Gas Conversion Kit 87380 1
2”Vent Screen +
3”Vent Screen
86231
86232 2 + 2
GAS: 2 x 3/4" (yellow)
CH:  2 x 3/4" (black)
DHW:1 x 1/2" (black)
3WV: 1 x P22 (black)
87599
N/A
N/A
85374
6
Outdoor Sensor Kit 86750 1
Plenum Sensor 87423 1
Decal, "GAS VENT DIRECTLY BELOW" 83008 1
2. About the Appliance
2.1 Items Included
When you open the packaging, you will nd the following items with the appliance. Check for each of the
following items before installing the appliance. The manual packet and kit box can be found inside the front
cover.
GF150 Installation Manual TRX150C Manuals and other Documentation
5
Seals:

6
2.2 Specications
The following table lists the specications for the appliance. Additional specications about water, gas,
electric, and air supplies (venting) appear in the Installation section.
GF150
Forced Air Heating Capacity 13,200 – 80,000 BTU/h
Cooling Capacity Up to 3 tons
Flow Rate
(Forced Air)
Heating / Ventilation 300 –1200 CFM
Cooling 360 –1200 CFM
Connection
Sizes
DHW Inlet / Outlet
⁄in NPT-MCH Supply / Return
Gas Inlet
Dimensions (W x H x D) 17⁄ in x 48 in x 35¾ in
Weight 220 lbs
Power Supply 120 V AC, 60 Hz, 15 A
TRX150C*
Energy Eciency (AFUE) 95%
Space Heating Capacity
(Hydronic + Forced Air) 13,200 – 120,000 BTU/h
DHW Capacity 13,200 – 150,000 BTU/h
Flow Rate
(DHW)
77°F (43°C) Temp Rise 3.6 GPM
Minimum 0.5 GPM
Water
Pressure
DHW Max. Pressure 125 PSI
Heat Exchanger MAWP 55 PSI
Venting
Length (intake) 2" (0 – 100 ft) | 3" (0 – 150 ft)
Length (exhaust) 2" (6 – 100 ft) | 3" (6 – 150 ft)
Materials PVC, CPVC, PP, SS
Installation Type Indoor, Fully Condensing
Flue System Category IV, Sealed Combustion Direct Vent, Power Vent
Burner System Premixed Fuel Modulation / Stainless Steel Burner
Ignition System Direct Electronic Spark Ignition / Flame Rectication
Gas Valve System Air Ratio Valve
Gas Supply Pressure
(from source)
NG 3.5 – 10.5 in w.c.
See Boiler Installation Manual (Supplied)LP 8 – 13 in w.c.
Gas Manifold Pressure (min-max) 0 in w.c.
Materials
Casing Cold Rolled Carbon Steel
Heating Coil Copper (tubes); Aluminum (ns)
Interconnecting piping Stainless steel, Copper, Brass (low-lead), Polymers (Viton™, EPDM, etc.)
Safety Devices
Flame Rectier Probe, Temperature Limit Control (190°F), Water Pressure Switch (min.
8 PSI), Freeze Protection, Blocked Condensate Pressure Switch, Condensate Trap,
Flue Temperature High Limit Sensor (210°F), Blocked Vent Pressure Switch,
Coil Freeze Protection (Plenum Sensor; Fan RPM Sensor)
*The TRX150C is the boiler component of the GF150.

7
1. ON / OFF Button (see NOTICE below)
2. Domestic Hot Water Adjustment Button +/-
3. MENU: (short press = User Menu);
(long press = Info Menu)
4. HISTORY Button - view last 10 errors
5. RESET Button (see NOTICE below)
6. OK – conrms menu selection
7. ESC – exits menu selection
8. Heating Temperature Adjustment Button +/-
9. Display
Digits Indicating:
• Boiler Status
• Temperature (°F) with bar level
• Error Codes (ERROR)
• Press ] RESET ] button request
(boiler lockout)
• Menu Settings
Technical assistance request
Flame detected with indication of
power level
CH Heating Operation Set
CH Heating Operation Active
DHW Operation Set
DHW Operation Active
Hot Water Comfort Activated (Combi Only)
OFF Boiler o with Antifreeze Function active
Antifreeze Function Active
AUTO
AutomaticTemperature Control activated
High Eciency Operation
(Low CH ow temperature)
Error signal - Display will also show a
code and description
Outdoor Sensor Connected - Optional
WiFi Active
ON/OFF Button
The button lights up (white) when the boiler is
electrically powered.
ON/OFF Button
The button is not lit in the event of an error or
power failure.
RESET BUTTON
The button lights up (red) in the event of a lockout
error. After pressing the Reset button to clear the
error condition, the button will ash for ve (5)
seconds.
NOTICE
AUTO 0
ON OFF
COMFORT
MENU PAR CODE
SRA
21 3 4 5 6 78 9
2.3 Display (HMI)

2.4 Components
The following diagram shows the key components of the appliance. A more detailed drawing of the boiler
itself is included in its manual. Component assembly diagrams and particular parts lists are included in the
Appendixes.
PRV (Pressure Relief Valve), 30 psi
Exhaust Duct
Ignition Transformer
Heat Exchanger
Combustion Blower
Circulation Pump
Condensate Trap
Control Box
Coil Return
Water Inlet Filter
APS (Air Pressure Sensor)
CH Supply Pipe
Condensate Drain
Tridicator
Gas Inlet Fitting
DHW Inlet Fitting
Field Wiring Panel
DHW Outlet Fitting
3-Way Valve
8
Display (HMI)
CH Supply Fitting
CH Return Fitting
Manual Purge Valve

2.5 Dimensions
The following diagrams show the dimensions of the appliance and the connections.
35.69
17.86
20.56
1.05
7.85
16.57
16.66
46.64
2.50
2.00 typ.
23.85
5.75
17.86
9.73
DHW outlet
CH supply
CH return
DHW inlet
Gas inlet
Rear
Top
Left Side
9

2.6 Rating Plate
This appliance comes from the factory congured for use with Natural Gas (NG). Before starting the
installation, check the rating plate located on the side of the appliance to ensure that it matches the gas type,
gas pressure, water pressure, and electrical supply available in the installation location. If the appliance does
not match each of these ratings, do not install the appliance. If conversion to Propane Gas is required, the
included LP Gas Conversion Kit must be used.
WARNING
●Be sure the gas type and electricity voltage match the rating plate. Using a dierent gas type will cause
abnormal combustion and appliance malfunction.
●Using abnormally high or low AC voltage may cause abnormal operation, and may reduce the life
expectancy of this product.
10
* No clearance required to front of unit if obstruction is
removable (such as a door or access panel), 24 inch
clearance if obstruction is permanent.
** Service access (to blower) must be maintained by
clearance or other means (door/access panel,
removable duct work, or front service clearance).
* Aucun dégagement nécessaire à l'avant de l'unité si
l'obstruction est amovible (comme une porte ou un panneau
d'accès), 24 po. si l'obstruction est permanente.
** L'accès de service (au ventilateur) doit être conservé, soit par
dégagement ou autres moyens (porte/panneau d'accès, un
conduit d'air amovible, ou acces à l'avant de la chaudière).
GF150
COMBINATION GAS COMBI BOILER / CENTRAL AIR HEATING
COMBINAISON CHAUDIÈRE COMBI / CHAUFFAGE DE L'ESPACE
Certified by
Certifie par
Made in Canada
Fabriques au Canada
NTI Boilers Inc. 30 Stonegate Drive
Saint John, NB E2H 0A4
Model
[Modèle]
Max
Input, MBH
[Entrée, kW]
Heating Capacity, MBH
[Capacité de chauffage, kW]
GF150 Nat./LP 120 [35.1]
FACTORY SET FOR NATURAL GAS
Field converted to Propane Gas :
ADJUSTÉ À L'USINE POUR GAZ NATUREL
Convertie au propane sur place :
Date: Date:
Gas Pressure [Pression de gaz]
Maximum Inlet Gas Pressure [Pression maximale d'entrée du gaz]
Minimum Inlet Gas Pressure [Pression minimum d'entrée du gaz]
Manifold Pressure [Pression d'admission]
Natural [Naturel]
Propane
10.5" w.c. [2.6 kPa]
3.5" w.c. [2.6 kPa]
0" w.c. n [0 kPa]
0" w.c. n [0 kPa]
8" w.c. [2.0 kPa]
13" w.c. [3.2 kPa]
Minimum Clearances [Dégagements minimum]
Important Information [Rensignesments Importants]
VOLTS
FOR YOUR SAFETY POUR VOTRE SÉCURITÉ
Do not store or use gasoline or other flammable
vapors and liquids in the vicinity of this or any other
appliance.
Ne pas entreposer ou utiliser de l'essence ou
d'autres vapeurs et liquides inflammables à proximité
de cet appareil ou de tout autre appareil.
Standard ANSI Z21.13-2017 • CSA 4.9
Gas-fired low pressure steam and
hot water boilers
CSA C22.2 No. 236 / UL 1995
Heating and Cooling Equipment
Serial No.
Serial No.
Model:
*628233733481*
Fuel
[Gaz]
Min
13.2 [3.9] 150 [43.9]
• Mixer necessary for LP conversion is provided.
• Failure to use correct gas can cause problems which can
result in death, serious injury or property damage.
• Le mélangeur nécessaire à la conversion au GPL est fourni.
• Le fait de ne pas utiliser le bon gaz peut causer des problèmes
qui peuvent mener à la mort, causer des blessures graves, ou
endommager la propriété.
Electrical Rating / Caractéristique Électrique
FREQ. PHASE RATED AMPS MCA MAX. CKT. BRK. RATED AMPS HP
120 60 Hz 1 15 A 15 A 15 A 7.7 A 1/2
INDOOR BLOWER MOTOR
• Use for Natural or LP Gas only.
• Maximum DHW Water Pressure = 125 psi
• Maximum CH Water Pressure = 30 psi
• Maximum Static Pressure = 0.8 in. w.c.
• Maximum Inlet Water Temperature = 180°F
• This appliance must be installed in accordance
with local codes, if any; if not, follow ANSI
Z223.1/NFPA 54 or CAN/CSA B149.1, Natural
Gas and Propane Installation Code, as applicable.
• Utilisez le gaz naturel ou LP seulement.
• Pression d'eau max. (ECS) = 862 kPa
• Pression d'eau max. (Chauffage) = 207 kPa
• Pression statique max. = 0.2 kPa
• Temp. maximale d'eau d'entrée = 82°C
• Cet appareil doit être installé conformément aux codes
locaux, le cas échéant ; sinon, suivez ANSI Z223.1 /
NFPA 54 ou CAN / CSA B149.1, Code d'installation du gaz
naturel et propane, le cas échéant.
BOILER RATING PLATE LOCATED ON SIDE OF BOILER CABINET
[PLAQUE SIGNALÉTIQUE DE LA CHAUDIÈRE SITUÉE SUR LE CÔTÉ DE LA CHAUDIÈRE]
NSF/ANSI 372
Minimum
[Minimum]
Service & Maintenance (Recommended)
[Service & entretien (recommandés)]
To Combustibles
[Au combustibles]
Top [dessus]
Back [arrière]
Front [avant]
Side [côté] 0
0
0
9 in [po]
0 or 24 in [po]**
0 or 24 in [po]*
0
as required [comme nécessaire]
2105262138174672
*2105262138174672*
Les capacités sont indiquées à des longueurs d'évent minimales;
l'entrée maximale sera réduit avec de plus longues longueurs d'évent.
Canada: pour altitudes de 2000 – 4500 pi [610 – 1372 m], réduire la
puissance de 10%. Reportez-vous au manuel.
États-Unis: pour les altitudes au dela de 2000 pi [610 m], réduire la
puissance de 4% par 1000 pi [305 m] au dessus du niveau de la mer.
Reportez-vous au manuel.
•
•
•
The capacities shown are at minimum vent lengths; maximum
input capacity will reduce with longer vent lengths.
Canada: for altitudes between 2000 – 4500 ft [610 – 1372 m], de-
rate capacity by 10%. See Installation & Operation Manual (IOM).
United States: for altitudes greater than 2000 ft, de-rate capacity
by 4% per 1000 ft above sea level. Refer to the IOM.
•
•
•
80 [23.4]
Hydronic
[Hydronique]
Forced Air
[Air pulsé]
DHW
[ECS]
150 [43.9]
M C V
D
C
B
A
D
C
B
A
4
1
4 3
2
1
BY TERM LAWS WE RESERVE THE PROPERTY OF THIS DRAWING WITH PROHIBITION OF USE AND REPRODUCTION
Precision level for dimentions witho ut tolerance indications has to be:
Document code
Drawing format
Designer
Date
Scale
Material
Treatment
Finishing
Description
Code
2
3
RL
Modification descripti on
A4
Designer Date
Code
ECN first creation
Revision
EN 22768-ISO 2768
Production Plant
30 Stonegate Drive,
Saint John, NB E2H 0A4
xx.xx.20xx
1:1
F
= 0 = 0 = 0
K L H
XX
Conformity requirements see the document named "R&D.TB005Tt-xx"
D. Grimmer
*Noclearance required to front of unit if obstruction is
removable (such as a door or access panel), 24 inch
clearance if obstruction is permanent.
**Serviceaccess (to blower) must be maintained by
clearance or other means (door/access panel,
removable duct work, or front service clearance).
*Aucundégagement nécessaire à l'avant de l'unité si
l'obstruction est amovible (comme une porte ou un panneau
d'accès), 24 po. si l'obstruction est permanente.
**L'accèsde service (au ventilateur) doit être conservé, soit par
dégagement ou autres moyens (porte/panneau d'accès, un
conduit d'air amovible, ou acces à l'avant de la chaudière).
GF150
COMBINATIONGAS COMBI BOILER / CENTRAL AIR HEATING
COMBINAISONCHAUDIÈRE COMBI / CHAUFFAGE DE L'ESPACE
Certifiedby
Certifiepar
Madein Canada
Fabriquesau Canada
NTIBoilersInc. 30 Stonegate Drive
SaintJohn, NB E2H 0A4
Model
[Modèle]
Max
Input,MBH
[Entrée,kW]
HeatingCapacity, MBH
[Capacitéde chauffage, kW]
GF150 Nat./LP 120[35.1]
FACTORYSETFOR NATURAL GAS
Fieldconvertedto Propane Gas :
ADJUSTÉÀL'USINE POUR GAZ NATUREL
Convertieaupropane sur place :
Date: Date:
GasPressure
[Pressiondegaz]
MaximumInletGas Pressure
[Pressionmaximaled'entrée du gaz]
MinimumInletGas Pressure
[Pressionminimumd'entrée du gaz]
ManifoldPressure
[Pressiond'admission]
Natural
[Naturel]
Propane
10.5"w.c.
[2.6kPa]
3.5"w.c.
[2.6kPa]
0"w.c.
n
[0kPa]
0"w.c.
n
[0kPa]
8"w.c.
[2.0kPa]
13"w.c.
[3.2kPa]
MinimumClearances
[Dégagementsminimum]
ImportantInformation
[RensignesmentsImportants]
VOLTS
FORYOURSAFETY POURVOTRESÉCURITÉ
Donotstore or use gasoline or other flammable
vaporsandliquids in the vicinity of this or any other
appliance.
Nepasentreposer ou utiliser de l'essence ou
d'autresvapeurset liquides inflammables à proximité
decetappareil ou de tout autre appareil.
StandardANSIZ21.13-2017 • CSA 4.9
Gas-firedlowpressure steam and
hotwaterboilers
CSAC22.2No. 236 / UL 1995
HeatingandCooling Equipment
SerialNo.
SerialNo.
Model:
*628233733481*
Fuel
[Gaz]
Min
13.2[3.9] 150[43.9]
•
Mixernecessaryfor LP conversion is provided.
•
Failuretouse correct gas can cause problems which can
result in death, serious injury or property damage.
•
Lemélangeurnécessaire à la conversion au GPL est fourni.
•
Lefaitde ne pas utiliser le bon gaz peut causer des problèmes
qui peuvent mener à la mort, causer des blessures graves, ou
endommager la propriété.
ElectricalRating/
CaractéristiqueÉlectrique
FREQ. PHASE RATEDAMPS MCA MAX.CKT.BRK. RATEDAMPS HP
120 60Hz 115A 15 A 15A 7.7A 1/2
INDOORBLOWERMOTOR
•Usefor Natural or LP Gas only.
•MaximumDHW Water Pressure = 125 psi
•MaximumCH Water Pressure = 30 psi
•MaximumStatic Pressure = 0.8 in. w.c.
•MaximumInlet Water Temperature= 180°F
•Thisappliance must be installed in accordance
with local codes, if any; if not, follow ANSI
Z223.1/NFPA 54 or CAN/CSA B149.1, Natural
Gas and Propane Installation Code, as applicable.
•Utilisezle gaz naturel ou LP seulement.
•Pressiond'eau max. (ECS) = 862 kPa
•Pressiond'eau max. (Chauffage) = 207 kPa
•Pressionstatique max. = 0.2 kPa
•Temp.maximale d'eau d'entrée = 82°C
•
Cetappareildoit être installé conformément aux codes
locaux, le cas échéant ; sinon, suivez ANSI Z223.1 /
NFPA 54 ou CAN / CSA B149.1, Code d'installation du gaz
naturel et propane, le cas échéant.
BOILERRATINGPLATE LOCATED ON SIDE OF BOILER CABINET
[PLAQUESIGNALÉTIQUEDE LA CHAUDIÈRE SITUÉE SUR LE CÔTÉ DE LA CHAUDIÈRE]
NSF/ANSI372
Minimum
[Minimum]
Service&Maintenance (Recommended)
[Service&entretien (recommandés)]
ToCombustibles
[Aucombustibles]
Top[dessus]
Back[arrière]
Front[avant]
Side[côté] 0
0
0
9in[po]
0or24 in [po]**
0or24 in [po]*
0
asrequired[comme nécessaire]
2105262138174672
*2105262138174672*
Lescapacitéssontindiquées à des longueurs d'évent minimales;
l'entréemaximaleseraréduit avec de plus longues longueurs d'évent.
Canada:pouraltitudesde 2000 – 4500 pi [610 – 1372 m], réduire la
puissancede10%.Reportez-vous au manuel.
États-Unis:pourlesaltitudes au dela de 2000 pi [610 m], réduire la
puissancede4%par 1000 pi [305 m] au dessus du niveau de la mer.
Reportez-vousaumanuel.
•
•
•
Thecapacitiesshown are at minimum vent lengths; maximum
inputcapacitywill reduce with longer vent lengths.
Canada:foraltitudes between 2000 – 4500 ft [610 – 1372 m], de-
ratecapacityby 10%. See Installation & Operation Manual (IOM).
UnitedStates:for altitudes greater than 2000 ft, de-rate capacity
by4%per 1000 ft above sea level. Refer to the IOM.
•
•
•
80[23.4]
Hydronic
[Hydronique]
ForcedAir
[Airpulsé]
DHW
[ECS]
150[43.9]

3. Installing the appliance
3.1 Choosing an installation location
This appliance must be installed indoors, in a dry
location free of dust and debris.
When choosing an installation location, you
must ensure that the location provides adequate
clearance for the appliance (including ductwork),
adequate venting and drainage options, and
sucient access to gas, water, and electrical
supplies. Carefully consider the following factors
when choosing an installation location:
Water quality
The following table shows the maximum
contaminant levels allowed, based on the EPA
National Secondary Drinking Water Regulations
(40 CFR Part 143.3). If you suspect that your water
is contaminated in any way, discontinue use of the
appliance and contact an authorized technician or
licensed professional.
Failure to do so could void the warranty.
Contaminant Maximum Allowable Level
Total Hardness Up to 200 mg/l (12 grains/gal.)
Aluminum 0.05 to 0.2 mg/l
Chloride Up to 250 mg/l
Copper Up to 1.0 mg/l
Iron Up to 0.3 mg/l
Manganese Up to 0.05 mg/l
pH 6.5 to 8.5
Sulfate Up to 205 mg/l
Total Dissolved Solids (TDS) Up to 500 mg/l
Zinc Up to 5 mg/l
Chlorine Up to 4 mg/l
Adequate drainage
●Maintain proper clearances from any openings in
the building.
●Install the appliance with a minimum clearance
of 12 in (300 mm) above an exterior grade, or as
required by local codes.
●Maintain a minimum clearance of 4 ft (1.2 m)
from heating and cooling vents.
●Do not enclose the vent termination.
●Install the exhaust vent in an area that is free from
obstructions and does not allow the exhaust to
accumulate.
●Do not install the appliance where moisture from
the exhaust may discolor or damage walls.
●Do not install the appliance in bathrooms,
bedrooms, or any other occupied rooms that are
normally kept closed or that are not adequately
ventilated.
11
Proximity to xtures and other appliances
Install the appliance near xtures that deliver or use
hot water, such as bathroom, kitchen, and laundry
room faucets. Select a location that minimizes the
water piping required between major xtures. If
the distances are long or the user requires“instant“
hot water, we recommend running a recirculation
line back to the appliance from the furthest xture.
Insulate as much of the hot water supply and
recirculation lines as possible.
Additionally, take care to locate the appliance such
that the supply and return ductwork can be installed
eciently, to limit noise and power consumption.
Combustion air quality
●Do not install the appliance in areas where dust
and debris may accumulate or where hair sprays,
spray detergents, chlorine, or similar chemicals are
used.
●Do not install the appliance in areas where
gasoline or other ammables are used or stored.
●Ensure that combustible materials are stored away
from the appliance and that hanging laundry
or similar items do not obstruct access to the
appliance or its venting.
NTI recommends that the connections be made in
the following order to ensure ease of installation,
given the limited space in the piping cabinet:
• Ductwork (could also be last)
• Condensate drain
• Domestic water (Inlet, then Outlet)
• Gas supply
• Electrical

3.2 Installation clearances
Install the appliance in an area that allows for service
and maintenance access to utility connections,
piping, lters, and traps. Based on the installation
location, ensure the following clearances are
maintained:
Minimum clearance: from
combustibles
for
service
Top 9 in as required
Back  
Front *  | 24 in*
Side (w/o connections)   | as required
Side (w/ connections)  as required
Side (Blower access)  24 in
Bottom  
* No clearance required to front of unit if obstruction is
removable (such as a door or access panel). 24 inch clearance if
obstruction is permanent.
Note The service clearances are
recommendations.
If you are unable to maintain those
specic clearances, be sure you have
an alternative plan as to how you are
going to service the unit.
When locating the appliance prior to completing
the ductwork and plumbing, it is essential that
sucient space be allotted for the installation and
maintenance of components such as:
• Pressure Relief Valves (PRV)
• Shut o and drain valves
• Thermostatic Mixing Valve (TMV)
• Expansion tank (optional)
• Condensate drain (and optional pump)
• Return air lter
• Circulating blower
12
3.3 Ducting the appliance
3.3.1 Supply ducting
The GF150 provides a standard-size anged supply
air outlet for easy installation of an evaporator coil or
supply plenum. Take care not to damage the heating
coil when installing ductwork to the supply air outlet
by using screws no longer than ¾”(0.75 in.).
As a space-saving measure, the top 10" of cabinet
may be removed (6 screws on the inside anges) to
reduce the overall height of the GF150 + A/C unit.
3.3.2 Return ducting
The return air may be delivered to the appliance via:
a) either side;
b) the back;
c) the bottom; or
d) any combination thereof, provided, in all cases,
that blower access is maintained.
REMOVABLE
SECTION
REMOVABLE
BOTTOM

JOINTS
REMOVABLE
BOOT
FILTER
RACK
RETURN
TRUNK
Should spatial restrictions preclude sucient clear-
ance in a side-return installation, it is recommended
that a joint (or joints) be made in the return ducting
such that the portion immediately adjacent to the
cabinet be removable to allow for blower access.
1313
3.3.3 Air ltration system
In all installations, an appropriate air ltration
system is recommended and must meet test
requirements in UL 900. Failure to install a lter
could lead to damage to and/or premature failure
of the space heating components.
In all cases, care must be taken to ensure that return
ducting is sealed against the inlet, such that the
entire airsteam is directed through the air lter.
Failure to do so could cause damage to the air
moving equipment and clogging of the heating
and/or cooling coils.
0.50 typ.
0.50 typ.
Max.: 18.5" x 14.5"
(268 sq. in.)
0.50 typ.
0.50 typ.
Max.: 16" x 14.5"
(232 sq. in.)
0.50 typ.
0.50 typ.
Max.: 18.5" x 14.5"
(268 sq. in.)
0.50 typ.
0.50 typ.
Max.: 16" x 14.5"
(232 sq. in.)
a) Side return:
When routing return air into the side of the unit, one
may remove the (lower) side panel entirely and
install a lter rack directly to the opening.
Alternatively, an opening may be cut into the central
area of the lower side panel (see indicated boundary
below).
If installing a cabinet-mounted lter rack, it may be
fastened (with self-tapping screws no longer than ¾”
(0.75 in.)) to both the remaining side panel material
and/or the cabinet, such that it overlaps the opening.
However, DO NOT drill holes or cut away any
material from the cabinet frame itself.
c) Bottom return:
A removable panel is included as part of the oor of
the GF150. To remove it, simply remove the 4 screws
from the panel’s front ange, and rotate the panel
about its rear ange to release it.
The resulting opening is 15.5”x 16.8” (260 sq. in.).
b) Rear return:
When routing return air
into the back of the unit,
an opening may be cut
within the connes of
the indicated boundary,
taking care not to damage
the blower housing within
when using longer tools.

3.4 Connecting the Condensate Drain
CAUTION
This condensing high eciency appliance has a
condensate removal system. Condensate is water
vapor derived from combustion products, similar to
that produced by an automobile when it is initially
started. It is very important that the condensate line
is sloped down away from the appliance and to a
suitable drain.
The condensate line must remain unobstructed. If al-
lowed to freeze in the line or obstructed in any other
manner, condensate can exit from the appliance tee,
resulting in potential water damage to property.
When installing a condensate pump, select one
approved for use with condensing appliances and
furnaces. The condensate pump should have an
overow switch to prevent property damage from
spillage.
Condensate from the appliance will be slightly acidic
(pH from 2 to 4.5). Check with your local gas com-
pany to determine if combustion condensate dis-
posal is permitted in your area. Install a neutralizing
lter if required by local codes.
NOTES:
1. Condensate line must be pitched at least ¼”per foot
to properly drain. If this cannot be done, or a very
long length of condensate hose is used, increase the
condensate line to a minimum of 1”ID and place a
tee in the line after the condensate neutralizer to
properly reduce vacuum lock in the drain line.
2. Use corrosion-resistant materials to drain
condensate. Use the included exible plastic hose
and exible tube, PVC, or CPVC pipe. PVC or CPVC
pipe must comply with ASTM D1785, F441, or D2665.
Cement must comply with
ASTM D2564 for PVC pipe
or F493 for CPVC pipe.
For Canadian applications, use CSA or ULC certied
exible tube, PVC or CPVC pipe, ttings, and cement.
3. If using exible tube, place an overow tee in the
tube line to prevent condensate backing up into the
appliance if the tube should kink.
Ensure the overow tee is positioned near a drain or
in a location that will not damage the surrounding
area.
14
4. Do not reduce the size of the condensate line.
The line must at minimum equal the diameter
of the line included with the appliance.
5. A frozen condensate line could result in a blocked
vent condition. It is very important to protect the
condensate line from freezing temperatures or any
type of blockage. In installations that may encounter
sustained freezing conditions, the use of heat tape is
recommended to avoid freezing of the condensate
line. It is also recommended to bush up the
condensate line size to 1" and terminate condensate
discharge as close to the unit as possible.
Longer condensate runs are more prone to freezing.
Damages due to frozen or blocked condensate lines
ARE NOT covered by warranty.
6. Support of the condensate line may be necessary to
avoid blockage of the condensate ow.
7. Local building codes may require an in-line
neutralizer to be installed (not included) to treat the
condensate. See facing gure.
If required by local authorities, a condensate lter
of lime crystals, marble, or phosphate chips will
neutralize slightly acidic condensate. Follow all the
installation instructions included with the neutralizer.
If a neutralizer is installed, periodic replacement of
the limestone (or neutralizing agent) will be required.
The rate of depletion of the limestone varies with
usage of the appliance.
During the rst year of operation, check the
neutralizer every few months for depletion.
8. Route the drain line to a nearby oor drain, laundry
tub, or condensate pump.
If the appliance condensate outlet is lower than the
drain, you must use a condensate removal pump.
9. An error will appear on the appliance display if the
condensate line is blocked. The boiler will not
operate with a blocked condensate line.
It is extremely important to have this condition
repaired by a qualied service technician.
10. Damages due to frozen or blocked condensate lines
or leaks ARE NOT covered by warranty.
11. To clean out condensate trap, see Maintenance
section.

15
WARNING
THE CONDENSATE TRAP MUST BE FILLED WITH
WATER BEFORE THE BOILER IS USED.
The siphon is lled with water during the air purging
procedure. See Filling Procedure in this manual for
further instructions.
Ensure the siphon contains water. If the siphon does
not contain water it must be lled. Open the manual
air vent on the main heat exchanger until lling is
complete. See diagram below.
Check the system pressure with the indicator gauge.
INSUFFICIENT WATER IN THE TRAP CAN CAUSE FLUE
GAS TO BE EXPELLED.
Failing to ensure the condensate trap is full of water
could result in property damage, severe personal
injury, or death.
50
Part 6 - Installing the Condensate Drain
NOTES:
1. Due to its ecient design, the boiler produces condensate (water)
as a normal by-product. This condensate is acidic, with a pH level
between 2 and 4.5. This condensate must be drained away from the
boiler and disposed in accordance with all local regulations.
2. Condensate line must be pitched at least ¼” per foot to properly
drain. If this cannot be done, or a very long length of condensate
hose is used, increase the condensate line to a minimum of 1”ID and
place a tee in the line after the condensate neutralizer to properly
reduce vacuum lock in the drain line.
3. Use corrosion-resistant materials to drain condensate. Use the
included exible plastic hose or ½” PVC and CPVC drain pipe
complying with ASTM D1785, F441, or D2665 may be used. Cement
must comply with ASTM D2564 for PVC pipe or F493 for CPVC pipe.
For Canadian applications, use CSA or ULC certied PVC or CPVC
pipe, ttings, and cement.
4. A frozen condensate line could result in a blocked vent condition.
It is very important to protect the condensate line from freezing
temperatures or any type of blockage. In installations that may
encounter sustained freezing conditions, the use of heat tape is
recommended to avoid freezing of the condensate line. It is also
recommended to bush up the condensate line size to 1” and
terminate condensate discharge as close to the unit as possible.
Longer condensate runs are more prone to freezing. Damages due
to frozen or blocked condensate lines ARE NOT covered by warranty.
5. Support of the condensate line may be necessary to avoid blockage
of the condensate ow.
6. Local building codes may require an in-line neutralizer to be installed
(not included) to treat the condensate. See Figure 58. If required
by local authorities, a condensate lter of lime crystals, marble, or
phosphate chips will neutralize slightly acidic condensate.
Follow all the installation instructions included with the neutralizer.
If a neutralizer is installed, periodic replacement of the limestone
(or neutralizing agent) will be required. The rate of depletion of
the limestone varies with usage of the boiler. During the rst year
of boiler operation, check the neutralizer every few months for
depletion.
7. Route the drain line to a nearby oor drain, laundry tub, or
condensate pump. If the boiler condensate outlet is lower than the
drain, you must use a condensate removal pump (kit p/n 554200
available from NTI).
NOTE: If a nearby laundry tub is used as a disposal for waste water from
the washing machine, draining the condensate into this tub allows the
soapy water discharge to neutralize the acidic condensate.
8. An error will appear on the boiler display if condensate line is
blocked. The boiler will not operate with a blocked condensate
line. It is extremely important to have this condition repaired by a
qualied service technician.
Boiler Manual Air Vent
This condensing high efciency boiler has a condensate removal
system. Condensate is water vapor derived from combustion
products, similar to that produced by an automobile when it is initially
started. It is very important that the condensate line is sloped down
away from the boiler and to a suitable drain.
The condensate line must remain unobstructed. If allowed to freeze
in the line or obstructed in any other manner, condensate can exit
from the boiler tee, resulting in potential water damage to property.
When installing a condensate pump, select one approved for use with
condensing boilers and furnaces. The condensate pump should have
an overow switch to prevent property damage from spillage.
Condensate from the boiler will be slightly acidic (pH from 2 to 4.5).
Check with your local gas company to determine if combustion
condensate disposal is permitted in your area. Install a neutralizing
lter if required by local codes.
CAUTION
THE CONDENSATE TRAP MUST BE FILLED WITH WATER BEFORE THE
BOILER IS USED. The siphon is lled with water during the boiler and
heating system purging procedure. See Purging Procedure in this
manual for further instructions.
Ensure the siphon contains water. If the siphon does not contain water
it must be lled. Open the manual air vent on the main heat exchanger
until lling is complete. See Figure 57. Check the system pressure with
a pressure gauge.
INSUFFICIENT WATER IN THETRAP CAN CAUSE FLUE GAS TO BE EXPELLED.
Failing to ensure the condensate trap is full of water could result in
property damage, severe personal injury, or death.
WARNING
Figure 57 - Condensate Trap Filling
REMOVAL TO OUTSIDE SOURCE)
NEUTRALIZER
1" x 3/4" PVC PIPE
OF 1/4" PER FOOT
CONNECTIONS
HORIZONTAL LINES MUST
RECOMMENDED:
TO OUTSIDE
CONDENSATE PIPING WITH PUMP
RECOMMENDED:
EXAMPLE: LOOSE FITING
PIPING SUPPORTS
RECOMMENDED:
BE INSTALLED WITH A PITCH
554200 LITTLE GIANT
CONDENSATE PUMP
OR DRAIN
CONDENSATE
REDUCER - SWEAT
BREAK AND OVERFLOW
(SUGGESTED SETUP FOR CONDENSATE
THROUGHOUT
RECOMMENDED:
CONNECTION FOR VACUUM
RECOMMENDED:
3/4" PVC PIPE SWEAT
PROVIDED FLEXIBLE
CONDENSATE HOSE
06/24/20
LP-723-B
BOILER
CONDENSATE REMOVAL
TO FLOOR DRAIN)
CONDENSATE PIPING
(SUGGESTED SETUP FOR
LP-723-A
06/24/20
BOILER
EXISTING DRAIN
RECOMMENDED
CONDENSATE NEUTRALIZER
BE INSTALLED WITH A PITCH
RECOMMENDED
H
ORIZONTAL LINES RECOMMENDED
HORIZONTAL
PIPING VERTICAL OR
PIPE REDUCER - SWEAT
3/4" PVC PIPE
OF 1/4" PER FOOT
LOOSE FITTING 1" X 3/4" PVC
PIPE HANGERS RECOMMENDE
D
BE USED TO SUPPORT
CONNECTION FOR VACUUM
BREAK AND OVERFLOW EXAMPLE:
PROVIDED FLEXIBLE
CONDENSATE HOSE
Choose
Drain
Side
Choose
Drain
Side

3.5 Connecting the Water Piping
WARNING
●Failure to follow the instructions in this
section WILL VOID the warranty and may
result in property damage, severe personal
injury, or death.
●The National Standard Plumbing Code, the
National Plumbing Code of Canada, and the
Uniform Plumbing Code limit heat transfer
uid pressure to less than the minimum
working pressure of the potable water system
up to 30 PSI maximum. In addition, the heat
transfer uid must be water or another non-
toxic uid having a toxicity of Class 1, as listed
in Clinical Toxicology of Commercial Products,
5th Edition. Failure to follow this warning
could result in property damage, severe
personal injury, or death.
CAUTION
●Do not apply a torch within 12”of the
appliance. If sweat connections are used, sweat
tubing to the adapter before tting adapter
to the water connections on the appliance.
Damages due to improper installation
practices ARE NOT covered by warranty.
●Where appropriate, use two wrenches when
tightening connections. Failure to prevent
piping connections from turning could cause
damage to components.
●Dielectric unions or galvanized steel ttings
must not be used in a system with this
appliance. Doing so WILL VOID the warranty.
Use only copper, brass, black iron, or stainless
steel ttings.
●The building piping system must meet or
exceed the piping requirements in this manual.
●The control module uses temperature
sensors to provide both high limit protection
and modulating temperature control. The
control module may also provide low water
protection by sensing the water level in the
heat exchanger. Some codes/jurisdictions may
require additional external controls.
3.5.1 General Plumbing Information
The water connections must be installed in
accordance with all local and national plumbing
codes, or any applicable standard which prevails.
• Pipe material must be suitable to meet local
codes and industry standards.
• The pipe must be cleaned and without blemish
before any connections are made.
• The size of the DHW pipes should be 3/4”
diameter, and the CH pipes should be 1”
diameter.
• Isolation (shut-o valves) should be used on both
the CH and DHW loops to ease future servicing.
• All piping should be insulated.
• If the appliance is installed with a backow
preventer in the DHW cold water supply line,
means shall be provided to control thermal
expansion. Contact the water supplier or a local
plumbing inspector on how to control this
situation.
It is recommended to install a sweat shut-o valve
and a union in the return and supply piping to ease
future servicing. If there is a backow preventer or
any type of a no return valve in the system, install an
additional tee here suitable for an expansion tank.
NOTE: The addition of a high temperature limiting
device is important if the appliance is to be
connected to a domestic hot water system.
3.5.2 Backow Preventer
Use a backow preventer specically designed for
hydronic boiler installations. This valve should be
installed on the cold water ll supply line per local
codes.
3.5.3 Expansion Tank
An expansion tank is provided with the GF150 for
standalone installations (without external hydronic
loads). For applications involving signicant external
CH piping, consult the relevant section (Part 4 – C)
of the TRX150C IOM for further details on specifying
and installing an expansion vessel.
16

3.5.4 CH and DHW Pressure Relief Valves
WARNING
To avoid water damage or scalding due to relief valve
operation:
●Discharge line must be connected to relief valve outlet and
run to a safe place of disposal. Terminate the discharge line
in a manner that will prevent possibility of severe burns or
property damage should the relief valve discharge.
●Discharge line must be as short as possible and the same
size as the valve discharge connection throughout its entire
length.
●Discharge line must pitch downward from the valve and
terminate at least 6”above the oor drain, making discharge
clearly visible.
●The discharge line shall terminate plain, not threaded, with a
material serviceable for temperatures above 375°F.
●Do not pipe discharge to any location where freezing could
occur.
●No valve may be installed between the relief valve and
appliance or in the discharge line. Do not plug or place any
obstruction in the discharge line.
●Test the operation of the relief valve after lling and pres-
surizing the system by lifting the lever. Make sure the valve
discharges freely. If the valve fails to operate correctly, imme-
diately replace with a new properly rated relief valve.
●Test relief valve at least once annually to ensure the
waterway is clear. If valve does not operate, turn the appli-
ance“OFF”and call a plumber immediately.
●Take care whenever operating relief valve to avoid
scalding injury or property damage.
FAILURE TO COMPLY WITH THE ABOVE GUIDELINES COULD RE-
SULT IN FAILURE OF RELIEF VALVE OPERATION, RESULTING IN POS-
SIBILITY OF SUBSTANTIAL PROPERTY DAMAGE, SEVERE PERSONAL
INJURY, OR DEATH.
This appliance has a high-temperature shut-o
switch built in as a standard safety feature.
Therefore, a“pressure only”relief valve is required.
DO NOT operate this appliance before the
supplied pressure relief valve (PRV) is installed
with sucient relieving capacity in accordance
with the ASME rating plate on the appliance.
WARNING
●The pressure relief valve must be installed with the
provided adaptor pipe in the top of the appliance as
detailed below.
●No other valves should be placed between the pressure
relief valve and the appliance. Failure to comply with
these guidelines can result in sub-stantial property
damage, personal injury, or death.
17
CH Loop
This appliance is provided with a CH PRV that
complies with the ANSI/ASME Boiler and Pressure
Vessel Code, Section IV (Heating Boilers). The
included 30 psi CH PRV must be installed at the top
of the boiler, using the included pipe adapter and
grommet, as illustrated below.
DO NOT install a relief valve with a pressure rating in
excess of 50 psi – the maximum allowable operating
pressure of the boiler. The relief valve capacity must
exceed the BTU/H input capacity of the boiler. To
install the pressure relief valve proceed as follows:
1. Remove the plastic cover on the top of the boiler.
2. Remove the hex cap on the ow pipe.
properly fitted into the top of the boiler cabinet.
3. Insert the pipe and gasket.
4. Connect the pressure relief valve and gasket.
NOTE: To maintain an airtight seal,
ensure the gasket boot is
properly tted into the top of
the boiler cabinet.

18
2. Install the 125 psi Pressure Relief Valve and tee
(supplied in Kit Box) onto the DHW Outlet pipe,
as shown below (note dierence between Left
and Right congurations).
Note When swapping DHW Inlet and Outlet
pipes, DO NOT swap the adapters
between the pipes and the boiler. Only
one contains a ow restrictor, and it must
remain on the boiler's DHW Inlet port.
Left conguration Right conguration
Note The 125 psi PRV may be installed in an
alternate location, farther downstream
on the DHW Hot Supply line, so long as it
remains on the appliance side of the Shut
O valve.
Right conguration
M C V
D
C
B
A
D
C
B
A
4
1
4 3
2
1
BY TERM LAWS WE RESERVE THE PROPERTY OF THIS DRAWING WITH PROHIBITION OF USE AND REPRODUCTION
Precision level for dimentions witho ut tolerance indications has to be:
Document code
Drawing format
Designer
Date
Scale
Material
Treatment
Finishing
Description
Code
2
3
RL
Modification descripti on
A4
Designer Date
Code
ECN first creation
Revision
EN 22768-ISO 2768
Production Plant
30 Stonegate Drive,
Saint John, NB E2H 0A4
xx.xx.20xx
1:1
F
= 0 = 0 = 0
K L H
XX
Conformity requirements see the document named "R&D.TB005Tt-xx"
D. Grimmer
Left conguration
M C
D
A
D
A
4
1
4
2
1
Precision level for dimentions witho ut tolerance indications has to be:
Document code
Drawing format
Designer
Date
Scale
Material
Treatment
Finishing
Description
Code
2
RL
Modication descripti on
A4
Designer Date
Code
ECN rst creation
Revision
Production Plant
xx.xx.20xx
1:1
F
= 0 = 0 = 0
L
XX
D. Grimmer
DHW Outlet
CH Supply
GAS Inlet
CH Return
DHW Inlet
DHW Inlet
CH Supply
GAS Inlet
CH Return
DHW Outlet
DHW Loop
The DHW piping must be provided with a DHW
pressure relief valve that complies with local codes,
but not less than valves certied as meeting the
requirements of Relief Valves for Hot Water Supply
Systems, ANSI Z21.22 / CSA4.4 by a nationally
recognized lab that maintains periodic inspection
of production listed equipment.
A DHW pressure relief valve included in the Kit Box
is to be installed in the DHW piping. DO NOT install
a DHW relief valve with a pressure rating greater
than 125 psi - the maximum allowable operating
pressure of the boiler’s DHW circuit. After installing
the relief valves and lling and pressurizing the
system, test the operation of the valves by lifting
the levers. Make sure the valves discharge freely.
If a valve fails to operate correctly, replace it with
a new relief valve. The relief valve capacity must
exceed the BTU/H input capacity of the boiler.
Installing the DHW PRV
1. The GF150 is factory-congured with all water,
gas, and condensate connections on the left.
The CH connections are xed to the left side,
but the DHW and GAS pipes may be ipped
(see connection diagram below).

19
3.5.5 Example plumbing layout
All eld DHW, CH, and Gas ttings are 3/4" NPT-M.
Example shown here without external CH loop
(ttings capped o at factory).
COLD
SUPPLY
HOT
(to xtures)
SHUT OFF
VALVES
DRAINS (typ.) PRESSURE
RELIEF
VALVE
(125 psi) -
2 potential
locations
EXPANSION
TANK
PRESSURE
RELIEF
VALVE
(30 psi)
GAS
IN
PRV
(to drain)

20
3.5.6 Filling the Appliance
The GF150 is factory-congured with a manual
lling valve to allow the appliance to be lled
from the domestic water supply without the
need for any additional ttings.
4. Open the Filling Valve (blue knob) ~ 5 turns.
Water will be heard lling the boiler circuit, and
air will begin to escape the vents.
5. The water entering the boiler circuit should
activate PURGE mode, which will engage the
pump to clear the air from the heating coil.
• Force PURGE manually: hold ESC for 5 s
• Stop PURGE manually: press ESC once
6. Monitor the pressure indicator and the
discharge from the Manual AIr Vent.
Continue lling until the discharge runs clear
(no air bubbles) while taking care to keep the
pressure at or below 20 psi.
Once the Manual Air Vent runs clear with water
(no air bubbles or pockets), close it to begin
pressurizing the system.
50
Part 6 - Installing the Condensate Drain
NOTES:
1. Due to its ecient design, the boiler produces condensate (water)
as a normal by-product. This condensate is acidic, with a pH level
between 2 and 4.5. This condensate must be drained away from the
boiler and disposed in accordance with all local regulations.
2. Condensate line must be pitched at least ¼” per foot to properly
drain. If this cannot be done, or a very long length of condensate
hose is used, increase the condensate line to a minimum of 1”ID and
place a tee in the line after the condensate neutralizer to properly
reduce vacuum lock in the drain line.
3. Use corrosion-resistant materials to drain condensate. Use the
included exible plastic hose or ½” PVC and CPVC drain pipe
complying with ASTM D1785, F441, or D2665 may be used. Cement
must comply with ASTM D2564 for PVC pipe or F493 for CPVC pipe.
For Canadian applications, use CSA or ULC certied PVC or CPVC
pipe, ttings, and cement.
4. A frozen condensate line could result in a blocked vent condition.
It is very important to protect the condensate line from freezing
temperatures or any type of blockage. In installations that may
encounter sustained freezing conditions, the use of heat tape is
recommended to avoid freezing of the condensate line. It is also
recommended to bush up the condensate line size to 1” and
terminate condensate discharge as close to the unit as possible.
Longer condensate runs are more prone to freezing. Damages due
to frozen or blocked condensate lines ARE NOT covered by warranty.
5. Support of the condensate line may be necessary to avoid blockage
of the condensate ow.
6. Local building codes may require an in-line neutralizer to be installed
(not included) to treat the condensate. See Figure 58. If required
by local authorities, a condensate lter of lime crystals, marble, or
phosphate chips will neutralize slightly acidic condensate.
Follow all the installation instructions included with the neutralizer.
If a neutralizer is installed, periodic replacement of the limestone
(or neutralizing agent) will be required. The rate of depletion of
the limestone varies with usage of the boiler. During the rst year
of boiler operation, check the neutralizer every few months for
depletion.
7. Route the drain line to a nearby oor drain, laundry tub, or
condensate pump. If the boiler condensate outlet is lower than the
drain, you must use a condensate removal pump (kit p/n 554200
available from NTI).
NOTE: If a nearby laundry tub is used as a disposal for waste water from
the washing machine, draining the condensate into this tub allows the
soapy water discharge to neutralize the acidic condensate.
8. An error will appear on the boiler display if condensate line is
blocked. The boiler will not operate with a blocked condensate
line. It is extremely important to have this condition repaired by a
qualied service technician.
Boiler Manual Air Vent
This condensing high efciency boiler has a condensate removal
system. Condensate is water vapor derived from combustion
products, similar to that produced by an automobile when it is initially
started. It is very important that the condensate line is sloped down
away from the boiler and to a suitable drain.
The condensate line must remain unobstructed. If allowed to freeze
in the line or obstructed in any other manner, condensate can exit
from the boiler tee, resulting in potential water damage to property.
When installing a condensate pump, select one approved for use with
condensing boilers and furnaces. The condensate pump should have
an overow switch to prevent property damage from spillage.
Condensate from the boiler will be slightly acidic (pH from 2 to 4.5).
Check with your local gas company to determine if combustion
condensate disposal is permitted in your area. Install a neutralizing
lter if required by local codes.
CAUTION
THE CONDENSATE TRAP MUST BE FILLED WITH WATER BEFORE THE
BOILER IS USED. The siphon is lled with water during the boiler and
heating system purging procedure. See Purging Procedure in this
manual for further instructions.
Ensure the siphon contains water. If the siphon does not contain water
it must be lled. Open the manual air vent on the main heat exchanger
until lling is complete. See Figure 57. Check the system pressure with
a pressure gauge.
INSUFFICIENT WATER IN THETRAP CAN CAUSE FLUE GASTO BE EXPELLED.
Failing to ensure the condensate trap is full of water could result in
property damage, severe personal injury, or death.
WARNING
Figure 57 - Condensate Trap Filling
7. Continue to ll while monitoring the system
pressure – NTI recommends lling the system to
20 psi.
8. Once system pressure is stable, close the blue
lling valve by turning it clockwise.
Make sure to continue turning the valve
past the point where the ow audibly stops
to fully seat the valve.
9. System pressure may uctuate during the rst
heat demand(s). If required, briey reopen the
manual lling valve (and/or purge valve) to
adjust the pressure back to 20 psi.
+
FILLING
VALVE
Fill to
20 PSI
1. Fill the DHW circuit.
2. Check that the Auto Air Vent
on the pump is open.
3. Open the Boiler Manual
Air Vent (Purge Valve)
~ 3 turns.