Greenheck IGX User manual

Part # 462876
®
MODEL IGX
Make-Up Air Unit
Installation, Operation and Maintenance Manual
Indirect Gas Fired Unit Installations
Units are listed for installation in the United States and Canada
•Installation of gas fired duct furnaces must conform with local building codes. In the absence of local
codes, installation must conform to the National Fuel Gas code, ANSI Z223.1 or in Canada,
CAN/CGA-B149 installation codes.
•All electrical wiring must be in accordance with the regulation of the National Electric Code,
ANSI/NFPA No. 70.
•Unit is approved for installation downstream from refrigeration units. In these conditions, condensate
could form in the duct furnace and provision must be made to dispose of the condensate.
**WARNING**
Improper installation, adjustment,
alteration, service or maintenance can
cause property damage, injury or death.
Read the installation, operating, and
maintenance instructions thoroughly
before installing or servicing this
equipment.
**FOR YOUR SAFETY**
The use and storage of gasoline or other
flammable vapors and liquids in open
containers in the vicinity of this appliance
is hazardous.
**FOR YOUR SAFETY**
If you smell gas:
1. Open windows.
2. Don’t touch electrical switches.
3. Extinguish any open flame.
4. Immediately call your gas supplier.

STORAGE
When a fan is not going to be in service for an extended amount of time, certain procedures should be followed
to keep the fan in proper operating condition.
• Rotate fan wheel monthly and purge bearings once every three months (If storage of fan is in a humid,
dusty or corrosive atmosphere, purge the bearings once a month).
• Cover unit with tarp to protect from dirt and moisture (Note: do not use a black tarp as this will promote
condensation)
• Energize fan motor once every three months
• Store belts flat to keep them from warping and stretching
• Store unit in location which does not have vibration
• After storage period, purge grease before putting fan into service
Improper storage which results in damage to the fan will void the warranty.
Storage and Lifting Instructions . . . . .2
Installation
Indoor Mounting
Horizontal and Downblast . . . . . . .3
Outdoor Mounting
Horizontal and Downblast
Discharge . . . . . . . . . . . . . . . . . . . .4
Horizontal and Downblast Discharge
with Optional Mixing Box . . . . . . . .5
Downblast Discharge Optional with
Combination Extension . . . . . . . .6-7
Venting for Indoor units . . . . . .8-17
Control Center Layout . . . . . . . . . . . . .18
Start-Up
Electrical . . . . . . . . . . . . . . . . . . . .19
Mixing Box . . . . . . . . . . . . . . . . . .20
Blower . . . . . . . . . . . . . . . . . . . . . .21
Furnace . . . . . . . . . . . . . . . . . .22-27
Evaporative Cooling . . . . . . . .28-29
Cooling Coils . . . . . . . . . . . . . . . . .30
Trouble Shooting
Blower . . . . . . . . . . . . . . . . . . . . . .31
Furnace . . . . . . . . . . . . . . . . . . . . .32
Evaporative Cooling . . . . . . . . . . .33
Maintenance
Routine . . . . . . . . . . . . . . . . . . . . .34
Furnace . . . . . . . . . . . . . . . . . . . . .35
Evaporative Cooling . . . . . . . . . . .36
Cooling Coils . . . . . . . . . . . . . . . . .37
Documentation . . . . . . . . . . . . . . . .38-39
Unit Layout . . . . . . . . . . . . . . . . . . . . . .40
Warranty . . . . . . . . . . . . . . . . . . . . . . . .40
TABLE OF CONTENTS
2
REPORT ANY DAMAGED EQUIPMENT TO THE SHIPPER IMMEDIATELY!
All units are shipped on a skid or packaged to minimize damage during shipment. The transporting carrier has
the responsibility for delivering all items in their original condition as received from Greenheck. The individual
receiving the equipment is responsible for inspecting the unit for obvious or hidden damage, recording any
damage on the bill of lading before acceptance and filing a claim (if required) with the final carrier. Some
accessory items are stored inside the unit during shipping. Care must be taken during installation to prevent
damage to units.

3
Installation Instructions for:
Indoor Mounted
Arrangement HZ and DB
Step 2 Install Ductwork
Good duct practices should be followed for all ductwork All ducts should be done in
accordance with SMACNA and AMCA guidelines.
Attach and secure the ductwork using self tapping screws.
Greenheck recommends attaching ductwork to collar using a rubber duct section at
the unit to minimize vibration.
Step 1 Install Unit
Using the factory provided lifting lugs, position the
unit in general area of mounting location. Before
lifting the unit into place, test lift the unit to verify
stability and balance. Lift and secure the unit into
position with threaded hanging rods and fasteners
to be attached to one of the following:
• Mounting Brackets (optional accessory)
• Platform (provided by others)
• Rails (provided by others)
Figure 1
Step 3 Install Venting Ductwork
The instructions for the indoor venting are listed on the following pages. Refer to
your unit submittal to determine the correct venting option instructions to follow.
LIFTING
Greenheck make-up air units must be lifted by the factory supplied lifting lugs only. The unit must also remain
upright as shipped, during lifting. THE USE OF ALL LIFTING LUGS IS MANDATORY WHEN LIFTING. All access
doors and panels must be closed during lifting to avoid damage.
To prevent damage to the unit cabinetry, use spreader bars. Spreader bars must be in position to stop cables
from rubbing the unit frame or panels. Before hoisting into position, test lift to insure stability and balance.
Avoid twisting or uneven lifting of the unit.
**IMPORTANT**
All factory provided lifting lugs must be used when lifting any unit. Failure to comply with this safety
precaution could result in property damage, serious injury or death.
Lifting Lugs
Lifting Lugs
Use spreader bar

4
Step 4 Install Unit
Use a crane and a spreader bar hooked to the factory
lifting lugs (as shown in the diagram) to lift and center
the unit on the curb/equipment support(s).
NOTE: THE USE OF ALL LIFTING LUGS IS
MANDATORY WHEN LIFTING UNIT.
Use self-tapping sheet metal screws to fasten unit to
the curb/equipment support(s).
Installation Instructions for:
Roof Mounted
Arrangement HZ and DB
Step 5 Assemble and Attach Weatherhood
The weatherhood can now be assembled and attached to the installed unit.
Assembly instructions are included with the weatherhood panels. If the optional
Evaporative Cooling module was selected, this step does not apply. Reference
the Installation Instructions for the Evaporative Cooling module.
Step 2 Install Ductwork
Good duct practices should be followed for all ductwork
All ducts should be done in accordance with SMACNA
and AMCA guidelines.
Arrangement DB: The use of a duct adapter is
recommended on a downblast arrangement to properly
align the ductwork with the supply unit. The duct
adapter is only a guide and is not intended to be used
as support for the ductwork.
Attach and secure the ductwork using self tapping
screws.
Greenheck recommends attaching ductwork to collar
using a rubber duct section at the unit to minimize
vibration.
Step 3 Apply Sealant
Before installing unit, apply a sealant around the
perimeter of the curb and duct adapter(s) to seal and
isolate the fan and minimize vibration. Note: Supply
duct adapter applies to arrangement DB only.
Step 1 Install Curb/Equipment
Support(s)
Position curb/equipment support(s) on the roof
(reference the CAPS submittal for placement of
curb/equipment support(s) in relation to the unit). Verify
that all unit supports are level, shim if necessary.
Attach curb to roof and flash into place. When attaching
the equipment support(s) to the roof, remove metal
cover, flash to wooden nailer and reinstall cover.
Figure 2
Metal Cover
Equipment
Support
Roof Curb
Use spreader bar
and lifting lugs.

5
Step 3 Apply Sealant
Before installing unit, apply a sealant around the
perimeter of the return air duct and supply duct
adapter to seal and isolate the fan and minimize
vibration. Note: Supply duct adapter applies to
arrangement DB only.
Step 1 Install Curb/Equipment
Support(s)
Position curb/equipment support(s) on the roof
(reference the CAPS submittal for placement of
curb/equipment support(s) in relation to the unit).
Verify that all unit supports are level, shim if
necessary. Attach curb to roof and flash into place.
When attaching the equipment support(s) to the roof,
remove metal cover, flash to wooden nailer and
reinstall cover.
Step 4 Install Unit
Use a crane and a spreader bar hooked to the
factory lifting lugs (as shown in the diagram) to lift
and center the unit on the curb/equipment
support(s).
NOTE: THE USE OF ALL LIFTING LUGS IS
MANDATORY WHEN LIFTING UNIT.
Use self-tapping sheet metal screws to fasten unit
to the curb/equipment support(s).
Installation Instructions for:
Roof Mounted with Optional Mixing Box
Arrangements HZ and DB
Step 5 Assemble and Attach Weatherhood
The weatherhood can now be assembled and attached to the installed unit.
Assembly instructions are included with the weatherhood panels. If the optional
Evaporative Cooling module was selected, this step does not apply. Reference
the Installation Instructions for the Evaporative Cooling module.
Supply Air
(Arrangement DB only)
Mixing Box
(Arrangement HZ and DB)
Step 2 Install Ductwork
Good duct practices should be followed for all
ductwork All ducts should be done in accordance
with SMACNA and AMCA guidelines.
Arrangement DB: The use of a duct adapter is
recommended on a downblast arrangement to
properly align the ductwork with the supply unit.
The duct adapter is only a guide and is not
intended to be used as support for the ductwork.
Attach and secure the ductwork using self tapping
screws.
Greenheck recommends attaching ductwork to
collar using a rubber duct section at the unit to
minimize vibration.
Figure 2A
Metal Cover
Equipment
Support
Use spreader bar
and lifting lugs.

6
Supply Duct with Duct
Adapter Installed
Exhaust Duct Installed
Sealant
Step 4 Apply Sealant
Before installing exhaust fan and supply unit,
apply a sealant around the perimeter of the
exhaust and supply duct adapter to seal and
isolate the fan and minimize vibration.
Supply
Ductwork
by Others
Exhaust
Ductwork
by Others
Metal Cover
Equipment
Support
Roof Curb
Exhaust
Supply
1 inch Inside
Flange
Step 1 Install Curb/Equipment Support(s)
Position curb/equipment support(s) on the roof
(reference the CAPS submittal for placement of
curb/equipment support(s) in relation to the unit). Verify
that all unit supports are level, shim if necessary.
Attach curb to roof and flash into place. When
attaching the equipment support(s) to the roof, remove
metal cover, flash to wooden nailer and reinstall cover.
Step 2 Install Combination Extension
Install combination extension over curb, use
wood screws to lag in place. Locate extension so
the tall vented side is over the exhaust opening,
as shown in illustration.
Step 3 Install Ductwork
Good duct practices should be followed for the
remaining ductwork.
The use of a duct adapter is recommended to
properly align the ductwork with the supply
unit. The duct adapter is only a guide and is not
intended to be used as support for the
ductwork.
Exhaust fan ductwork must be built in
accordance with NFPA 96 and any local codes.
Ductwork terminating at the fan should be
square in shape or of smooth transition so as
not to affect the fan performance.
Installation Instructions for:
Roof Mounted with Optional Combination Extension
Downblast Discharge
Arrangement DBC

7
Model CUBE
Exhaust Fan
Step 5 Install Exhaust Fan
Install CUBE exhaust fan on curb extension.
Fasten with self-tapping sheet metal screws
through existing holes in curb cap. NFPA 96
requires the exhaust fan be hinged.
Greenheck offers an optional hinge kit with
restraining cables and a grease trap with
drain connection. Install these options at this
time.
NOTE: Installing the exhaust fan prior to the
supply unit will allow for easier installation of
options.
Step 6 Install Supply Unit
Use a crane and a spreader bar hooked
to the factory lifting lugs (as shown in the
diagram) to lift and center the unit on the
curb/equipment support(s).
NOTE: THE USE OF ALL LIFTING LUGS
IS MANDATORY WHEN LIFTING UNIT.
Use self-tapping sheet metal screws to
fasten unit to the curb/equipment
support(s).
Use caution to avoid damaging exhaust
fan when installing supply unit.
Step 7 Assemble and Attach Weatherhood
The weatherhood can now be assembled and attached to
the installed unit. Assembly instructions are included with
the weatherhood panels. If the optional Evaporative Cooling
module was selected, this step does not apply. Reference
the Installation Instructions for the Evaporative Cooling
module.
Figure 3
Use spreader bar
and lifting lugs.

8
1. Do not install units in locations where flue products
can be drawn into adjacent building openings such
as windows, fresh air intakes, etc. Distance from
vent terminal to adjacent public walkways,
adjacent buildings, operable windows, and
building openings shall conform with the local
codes. In the absence of local codes, installation
shall conform with the National Fuel Gas Code,
ANSI Z223.1, or the CAN/CGA B-149 Installation
Codes.
2. Building materials that will be affected by flue
gases should be protected.
3. Avoid locating in an area where deep snow is likely
to accumulate. During the winter months, keep
snow clear on the access side of the unit to
prevent any blockage of combustion air inlet or
flue exhaust openings (outdoor units only).
4. Maintain minimum horizontal clearance of 4 feet
from electric meters, gas meters, regulators, and
relief equipment. In Canada, the minimum
clearance is 6 feet.
5. Local codes may supercede any of the above
provisions.
6. Be sure that the minimum clearances to
combustible materials are maintained.
Unit Clearances to Combustible Materials
Indoor units, clearance from combustible
material are determined by the National
Fuel Gas Code and/or other local codes.
Outdoor units, the combustion blower
discharge must be located a minimum of
42 inches from any combustible materials.
1. Do not modify or obstruct the combustion air inlet
cover or the combustion blower weatherhood.
2. During winter months, periodically clear snow from
the access side of the unit to prevent blockage of
the inlet and exhaust openings.
3. Do not add vents other than those supplied by the
manufacturer.
General Venting and Combustion Air
Venting Instructions:
Outdoor Units
Combustion Air Inlet Cover
Combustion Blower
Exhaust Weatherhood

9
1. Installation of venting must conform with local
building codes. In the absence of local codes,
installation must conform with the National Fuel
Gas Code, ANSI Z223.1 or in Canada, CAN/CGA-
B149 installations codes.
2. The classification for vertical and horizontal venting
of all units is category III. The ANSI requirements
for vents classified as category III is that they must
be gas tight. Seal the joints with a metallic tape or
silastic suitable for temperatures up to 350 degrees
F. the venting system shall be installed in
accordance with these instructions.
3. All pipe is field supplied by others. For the vent
pipe, use pipe approved for a category III appliance
or single wall, 26 gauge or heavier galvanized vent
pipe. For the combustion air pipe on separated
combustion units, sealed single-wall galvanized air
pipe is recommended. Refer to the National Fuel
Gas Code for additional piping guidelines.
4. Select the vent and combustion air pipe size from
the tables (1) and (2) shown on the following pages.
Select the size of the vent and combustion air pipe
that fits the flue outlet and combustion air intake.
Use only the pipe size specified.
5. Install the vent and combustion air pipes with
minimum downward slopes (from the unit) of 1/4
inch per foot, suspend securely from overhead
structures at points no greater than 3 feet apart.
Fasten individual pipe lengths together with at least
three corrosion resistant sheet metal screws.
6. For the vent pipe, a minimum of 12 inches of
straight pipe is recommended at the flue outlet
before any elbows.
7. Avoid venting through unheated spaces if possible.
To minimize condensation, insulate any vent runs
greater than 5 feet that must pass through an
unheated space.
8. For the combustion air pipes, long runs in cold
climates may require insulation to prevent the
buildup of condensation on the outside of the pipes
where the pipe passes through heated spaces.
9. Vertical combustion air pipes should be fitted with a
tee with a drip leg and clean out cap to prevent any
moisture in the combustion air pipe from entering
the unit. The drip leg should be cleaned out
periodically during the heating season.
10.For separated combustion systems, the wall
thickness for the purpose of venting is 1 inch
minimum, 48 inches maximum.
•Standard Indoor Venting (uses building air for combustion)
•Separated Combustion Concentric Venting (uses outside air for combustion, one exterior roof or wall
penetration)
•Separated Combustion 2-Pipe Venting (uses outside air for combustion, two exterior roof or wall penetrations)
For each method, the units can be vented horizontally through an exterior wall or vertically through the roof.
Refer to the following pages for specific venting instructions. Construct the vent system for the selected
method, as shown in these instructions. When looking in the direction of airflow, the venting is on the right side
of the unit.
Furnace Vent Standard Separated Combustion Separated
Size Lengths Indoor Concentric Combustion 2-pipe
100 - 300 min 5 ft. 5 ft. 5 ft.
max 70 ft. 70 ft. 70 ft.
350 - 400 min 5 ft. 5 ft. 5 ft.
max 70 ft. 70 ft. 50 ft.
VENT LENGTHS FOR EXHAUST AND COMBUSTION AIR
Venting Instructions:
Indoor Units
Venting Methods for Indoor Units

10
Standard Indoor Venting
This refers to using one penetration through an
exterior wall or roof for venting the flue exhaust. The
combustion air is supplied from the air inside the
building. Units must not be installed in a potentially
explosive, flammable, or corrosive atmosphere. To
prevent premature heat exchanger failure, do not
locate units where chlorinated, halogenated, or acid
vapors are present in the atmosphere.
Combustion Air Requirements
When units are installed in tightly sealed buildings,
provisions should be made to supply adequate amount
of infiltration air from the outside. The rule of thumb is
that an opening of one square inch should be provided
for every 1000 BTU per hour of input rating.
Vent Construction
To vent using this method, the vent terminal supplied
with the units must be used. Construct the vent system
as shown in drawings and reference the tables for vent
pipe sizes. The minimum vent length is 5 feet and the
maximum vent length is 70 feet. The total equivalent
vent length must include elbows. The equivalent length
of a 4 inch elbow is 6 feet and the equivalent length of
a 6 inch elbow is 10 feet.
Standard Horizontal Venting
A = 12 inches
A
Pitch vent pipe
downward from furnace
.25 inches per foot
Exhaust Vent
Terminal
EXHAUST
Exterior Wall
Air Inlet
Venting Instructions:
Standard Indoor Units

11
Furnace Flue
Size Outlet
100 - 150 4 inch
200 - 400 6 inch
Standard Vertical Venting
A1
A=12 inch minimum
A1 = 12 inch minimum, but should
size according to expected
snow depth.
Standard Indoor Venting
EXHAUST
Exhaust Vent
Terminal
Air Inlet
Building Roof
Venting Instructions:
Standard Indoor Units
A
Table 1
All measurements shown are diameters.

12
Installing the Concentric Venting Adapter
Concentric venting allows both the vent pipe and combustion air pipe to pass through one hole in the exterior
of a building. This can be accomplished by horizontal venting through an exterior wall or vertical venting
through the roof. A vent kit is required for either method of venting.
**WARNING**
The concentric venting adapter is not designed for installations
on the exterior of buildings. Refer to the following diagrams
and instructions for proper installation instructions.
1. Determine the location of the Concentric Venting
Adapter (CVA) based on the method of venting to
be used (horizontal or vertical) and any clearances
that must be maintained (follow all codes
referenced in these instructions). Field supplied
mounting brackets are used to mount the CVA to
the wall or roof. It can be mounted flush to the wall
or it can be offset.
2. Determine the length of the mounting brackets and
fabricate from corrosion resistant material. Using
corrosion resistant screws, fasten the mounting
brackets to the CVA.
3. Determine the length of the vent pipe that must be
attached to the vent outlet on the concentric side of
the box. Make sure to add the thickness of the wall
or roof and the length of the mounting brackets.
Attach the proper length of pipe to the CVA using
three corrosion resistant sheet metal screws and
seal this joint using metallic tape, silastic, or caulk
suitable for temperatures up to 350 degrees F. If
using metallic tape, wrap the tape around the pipe
two full turns.
4. Determine the length of the combustion air pipe
that must be attached to the combustion air intake
on the concentric side of the CVA. Cut the pipe
length making sure to add the thickness of the wall
or roof and the length of the mounting brackets.
Slide the combustion air pipe over the vent pipe
and attach the proper length of pipe to the CVA
using three corrosion resistance sheet metal
screws.
5. Place the entire CVA assembly (with piping and
support bracket attached) through the hole in the
wall or roof and verify that all distances and pipe
lengths requirements as specified in these
instructions are net. Attach this assembly to the
wall or roof using appropriate fasteners.
Furnace Flue Air Flue Air
Size Outlet Inlet Outlet Inlet
100 - 150 4 inches 4 inches 4 inches 6 inches
200 - 400 6 inches 6 inches 6 inches 8 inches
Non-Concentric
Side Vent Connections
Concentric Side
Vent Connections
Venting Instructions:
Concentric Venting
Table 2
All measurements shown are diameters.

13
Concentric Venting
Adapter - 4 inch diameter
(CVA-4)
Concentric Venting
Adapter - 6 inch diameter
(CVA-6)
Flue Outlet
Concentric Side
Air Inlet
Concentric Side
CVA
Flue Outlet
Non-Concentric Side
Air Inlet
Non-Concentric Side
Flue Outlet
Concentric Side
Air Inlet
Concentric Side
Flue Outlet
Non- Concentric Side
Air Inlet
Non-Concentric Side
CVA
Venting Instructions:
Concentric Venting Adapter
CVA-4
Venting Instructions:
Concentric Venting Adapter
CVA-6

Separated Combustion Concentric Venting Kit - Horizontal
Furnace Size 100 - 150 mbh 200 - 400 mbh
Kit contents: (1) 4 inch vent terminal (1) 6 inch vent terminal
(1) 6 inch inlet guard (1) 8 inch inlet guard
(1) concentric adapter (1) concentric adapter
14
A
1. The vent pipe must terminate with the vent
terminal (supplied in the venting kit) for horizontal
venting. The venting kit includes the concentric
venting adapter, vent termination cap and the air
inlet guard.
2. The combustion air pipe must terminate at least 2
inches from the wall. this will prevent water from
running down the wall and into the pipe and
allows for easy installation of the combustion air
intake guard.
3. Caulk between the wall and the air intake pipe.
4. Maintain 12 inches from the combustion air inlet
guard to the back of the vent terminal.
5. Now attach the combustion air intake guard by
placing the guard on the end of the pipe. Bend
the mounting tabs over and onto the pipe. Fasten
the guard to the intake pipe using non-corrosive
screws.
Horizontal Venting
EXHAUST
COMBUSTION AIR
Exterior Wall
B
C
C
Exhaust Vent
Terminal
A = 12 inch minimum
B = 2 inch minimum
C = Field supplied mounting brackets
Combustion Air
Inlet Guard
Pitch vent pipe downward
from furnace .25 inches per
foot
Venting Instructions:
Concentric Venting - Horizontal
The venting parts listed above are supplied by Greenheck.
All vent piping is FIELD SUPPLIED by others.
All measurements shown are diameters.

1. The vent must terminate with the vent terminal,
supplied in the vent kit.
2. The combustion air pipe must terminate with the
cap (supplied in the venting kit). This cap is specially
designed to work with the concentric vent system.
The venting kit includes the concentric adapter box,
vent termination cap, and an air inlet terminal.
3. The bottom of the air intake pipe must terminate
above the snow line, or at least 12 inches above the
roof, which ever is greater.
4. The bottom of the vent cap must terminate at least
12 inches above the top of the air intake cap.
5. To attach the caps, slide the combustion air cap
over the vent pipe and fasten it to the combustion
air pipe with at least 3 non corrosive fastener.
6. Caulk the gap between the combustion air cap and
the vent pipe with silicone sealant, or other
appropriate sealants suitable for metal to metal
contact and temperatures of 350 degrees F.
Vertical Venting
Exhaust Vent Terminal
Combustion Air Inlet
Terminal
A1
A
A
B
Building Roof
C
C
EXHAUST
COMBUSTION AIR
Tee with drip leg and
cleanout cap
A=12 inch minimum
A1= 12 inch minimum, but should size
according to expected snow depth.
B=12 inches
C=Field supplied mounting brackets
Venting Instructions:
Concentric Venting - Vertical
The venting parts listed above are supplied by Greenheck.
All vent piping is FIELD SUPPLIED by others.
Separated Combustion Concentric Venting Kit - Vertical
Furnace Size 100 - 150 mbh 200 - 400 mbh
Kit contents: (1) 4 inch vent terminal (1) 6 inch vent terminal
(1) 6 inch inlet terminal (1) 8 inch inlet terminal
(1) concentric adapter (1) concentric adapter
15
All measurements shown are diameters.

16
1. Construct the vent system as shown below. Looking
in the direction of airflow, the venting is on the right
side of unit.
2. The termination of horizontally vented systems must
extend 12 inches beyond the exterior surface of an
exterior wall.
3. The combustion air pipe must be a minimum of 12
inches below the vent pipe and 24 inches from the
exterior wall.
4. Support the vent and combustion air pipe as shown
below.
Horizontal Venting
Exterior Wall
B
A
EXHAUST
COMBUSTION AIR
Pitch vent pipe downward from
furnace .25 inches per foot
C
Field Supplied
Support Brackets
The venting parts listed above are supplied by Greenheck.
All vent piping is FIELD SUPPLIED by others.
A = 24 inch minimum
B = 12 inch minimum
C = 12 inch minimum
Exhaust Vent
Terminal
Combustion Air
Inlet Terminal
Venting Instructions:
2-Pipe Horizontal
Separated Combustion 2-Pipe Venting Kit - Horizontal
Furnace Size 100 - 150 mbh 200 - 400 mbh
Kit contents: (2) 4 inch vent terminal (2) 6 inch vent terminal
All measurements shown are diameters.

17
1. Construct the vent system as shown below.
Looking in the direction of airflow, the venting is on
the right side of unit.
2. The bottom of the combustion air cap must be
located above the snow line or 12 inches above the
roof, which ever is greater.
3. The vent must terminate at least 12 inches above
and 12 inches horizontally from the combustion air
inlet.
Vertical Venting
A
A
A
BC
A1
A=12 inch minimum
A1 = 12 inch minimum, but should size
according to expected snow depth.
B=24 inch minimum
C=12 inch minimum
EXHAUST
COMBUSTION AIR
Tee with drip leg and
cleanout cap.
Combustion Air
Inlet Terminal
Exhaust Vent
Terminal
The venting parts listed above are supplied by Greenheck.
All vent piping is FIELD SUPPLIED by others.
Separated Combustion 2-Pipe Venting Kit - Vertical
Furnace Size 100 - 150 mbh 200 - 400 mbh
Kit contents: (2) 4 inch vent terminal (2) 6 inch vent terminal
Venting Instructions:
2-Pipe Vertical
All measurements shown are diameters.

18
1. Main Power Connection -Recommended location is directly above the horizontal divider that separates the
blower and control center access panels. Bring the main power and optional
exhaust fan wiring into the unit at this location.
2. Control Transformer - Provides 24 Volt power for fan and the furnace controls.
3. Transformer Fuses - Provides proper fusing for control transformer.
4. Motor Fuses - Provides proper fusing for supply and exhaust fan motors.
5. Motor Starters - 24 Volt magnetic contacts for starting motors, comes standard with electronic
overload. Can be provided with auxiliary contacts.
Optional Exhaust Starter and Fusing (Shown)
6. Terminal Strip -24 Volt power at strip for control wiring.
Note: This is a typical control center, an exact wiring diagram is shipped with the unit.
Control Center Layout
DANGER !
High voltage electrical input is needed for this equipment. This work should
be performed by a qualified electrician.
Before connecting power to the unit, read and understand the following instructions and wiring diagrams.
Complete wiring diagrams are attached inside the door(s) of the unit.
All wiring should be done in accordance with the National Electrical Code ANSI/NFPA-70 latest edition and any
local codes that may apply. In Canada, wiring should be done in accordance with the Canadian Electrical Code.
The equipment must be properly grounded.
Figure 4: Unit Control Center
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5
6
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For all units:
1. The unit’s nameplate states the voltage and total amperage (MCA’s) required.
The main feeder supplying power to the unit should be sized for the nameplate voltage and
amperage.
2. For the main power connection, a field supplied opening will be needed. The recommended location is
through the control center cabinet, refer to figure 4.
3. Bring the supply power to the unit and connect to the disconnect switch.
Make sure that the disconnect lugs are securely tightened.
4. Connect optional remote control panel wiring to terminal strip in the control center.
Greenheck’s standard control voltage is 24 VAC.
5. Wire any optional remote temperature selectors at this time. These wires should be in shielded cable or
separate conduit.
6. When an optional convenience outlet is provided, a separate power supply (115/60/1) must be provided
to the receptacle. This circuit must be on a ground fault breaker.
7. Wire power lead for CUBE exhaust fan through side breather tube. The power lead should be of
sufficient length as to allow the CUBE fan to hinge open and to allow service of the burner controls.
NOTE: Any wiring running through the unit in the airstream must be protected by
flexible conduit, metal clad cable or raceways.
CAUTION !
Any wiring deviations may result in personal injury or property damage. Greenheck is not
responsible for any damage to, or failure of the unit caused by incorrect field wiring.
Start-Up Instructions:
Electrical
Sequence for Wiring Units
IMPORTANT: Use minimum 14 ga. wire for 24 volt control power.
Control wire resistance should not exceed 0.75 ohms (approximately 285 feet total
length for 14 ga. wire; 455 feet total length for 12 ga. wire). If wire resistance
exceeds 0.75 ohms, an industrial-style, plug-in relay should be added to the unit
control center and wired in place of the remote switch. The relay must be rated for
at least 5 amps and have a 24 Vac coil. Failure to comply with these guidelines may
cause motor starters to “chatter” or not pull in which can cause contactor failures
and/or motor failures.

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Start-Up Instructions:
Optional Mixing Box
Control Options:
Night Setback requires field wiring from unit to the thermostat.
This options enables a make-up unit to operate in 100% return air mode at night (unoccupied periods) so
that a desired space temperature may be maintained at the lowest operational cost. During daytime
(occupied) hours, the unit operates as a 100% make-up air unit with furnace(s) controlled off a field
adjustable discharge temperature setting. This package includes a Deluxe Programmable Thermostat
with a time clock that enables the customer to program occupied and unoccupied operation periods.
Building Pressure Control requires field wiring from the unit to the factory
provided remote control panel.
This option enables outdoor air and return air dampers modulate to maintain the desired building
pressure. The building pressure set point is field adjustable using a photohelic gauge mounted on a
factory provided remote control panel.
Potentiometer Control requires field wiring from the unit to the factory provided
remote control panel.
This option enables manual control of the outdoor air and return air damper positions. Damper positions
are controlled with a potentiometer mounted on a remote control panel.
Figure 5: Mixing Box with optional filters and dampers
Mixing Box