Carrier 336771-752-CBP User manual

1
336771---752---CBP
336771---756
336771---757
336771---758
336771---759---CBP
336771---761
336771---763
336771---764
Installation Instructions
REPLACEMENT PRIMARY HEAT EXCHANGER KIT
FOR USE WITH 35---IN. (889 mm)
HIGH EFFICIENCY GAS FURNACES
NOTE: Read the entire instruction manual before starting the
installation.SAFETY CONSIDERATIONS
Improper installation, adjustment, alteration, service, maintenance,
or use can cause explosion, fire, electrical shock, or other
conditions which may cause death, personal injury, or property
damage. Consult a qualified installer, service agency, or your
distributor or branch for information or assistance. The qualified
installer or agency must use factory--authorized kits or accessories
when modifying this product. Refer to the individual instructions
packaged with the kits or accessories when installing.
Follow all safety codes. Wear safety glasses, protective clothing,
and work gloves. Have a fire extinguisher available. Read these
instructions thoroughly and follow all warnings or cautions
included in literature and attached to the unit. Consult local
building codes, the current editions of the National Fuel Gas Code
(NFGC) NFPA 54/ANSI Z223.1 and the National Electrical Code
(NEC) NFPA 70.
In Canada, refer to the current editions of the National Standards of
Canada CAN/CSA--B149.1 and .2 Natural Gas and Propane
Installation Codes, and Canadian Electrical Code CSA C22.1.
Recognize safety information. This is the safety--alert symbol !!.
When you see this symbol on the unit and in instructions or
manuals, be alert to the potential for personal injury.
Understand the signal words DANGER,WARNING,and
CAUTION. These words are used with the safety--alert symbol.
DANGER identifies the most serious hazards which will result in
severe personal injury or death. WARNING signifies hazards
which could result in personal injury or death. CAUTION is used
to identify unsafe practices which may result in minor personal
injury or product and property damage. NOTE is used to highlight
suggestions which will result in enhanced installation, reliability, or
operation.
!WARNING
FIRE, EXPLOSION, ELECTRICAL SHOCK
HAZARD
Failure to follow this warning could result in personal injury,
death and/or property damage.
The ability to properly perform maintenance on this equipment
requires certain knowledge, mechanical skills, tools, and
equipment. If you do not possess these, do not attempt to
perform any maintenance on this equipment other than those
procedures recommended in the User’s Manual.
!WARNING
FIRE, EXPLOSION, ELECTRICAL SHOCK AND
CARBON MONOXIDE POISONING HAZARD
Failure to follow this warning could result in personal injury,
death and/or property damage.
Improper installation, adjustment, alteration, service,
maintenance, or use can cause carbon monoxide poisoning,
explosion, fire, electrical shock, other conditions, which could
result in personal injury or death. Consult your distributor or
branch for information or assistance. The qualified installer or
agency must use only factory--authorized kits or accessories
when servicing this product.
!WARNING
ELECTRICAL SHOCK, FIRE OR EXPLOSION HAZARD
Failure to follow this warning could result in personal injury or
death, or property damage.
Before installing, modifying, or servicing system, main electrical
disconnect switch must be in the OFF position and install a
lockout tag. Check accessories and cooling unit for additional
electrical supplies that must be shut off during the furnace
servicing. There may be more than one disconnect switch. Lock
out and tag switch with a suitable warning label. Verify proper
operation after servicing.
CUT HAZARD
Failure to follow this caution may result in personal injury.
Sheet metal parts may have sharp edges or burrs. Use care and
wear appropriate protective clothing and gloves when
handling parts
CAUTION
!
INTRODUCTION
This instruction covers installation of the Replacement Primary
Heat Exchanger Kit, Part No. 336771--752--CBP, --756, --757,
--758, --759--CBP, --761, --763, --764 in 35--in. (889 mm) tall,
condensing gas furnaces. See Table 2 for kit usage.
NOTE: DO NOT use a releasing agent on parts that will be sealed
with RTV.
NOTE: DO NOT substitute any other type of RTV sealant for
those listed below.
The low adhesion sealant used on the Coupling Box cover is
Novaguard RTV 400--900t, P/N PF 680002.

2
DESCRIPTION AND USAGE
Use this Primary Heat Exchanger kit to replace a failed primary
heat exchanger. This Primary Heat Exchanger Kit contains the
following items.
See Table 1 for kit contents and Table 2 for where used.
Table 1 – Kit Contents
Kit No. 336771---752---CBP
Part No. Description Quantity
336771--- 702 HX & Panel Assy. 1
FAW5808B Screw 51
336828--- 401 Gasket 2
336839--- 401 Gasket, Coll Box 1
336803--- 402 Cell Panel Insulation 1
AL90AZ173 Screw 12
IIK---336771--- 04 Instructions 1
Kit No. 336771---756
Part No. Description Quantity
336771--- 706 HX & Panel Assy. 1
FAW5808B Screw 56
336828--- 401 Gasket 2
336839--- 403 Gasket, Coll Box 1
336803--- 406 Cell Panel Insulation 1
AL90AZ173 Screw 12
IIK---336771--- 04 Instructions 1
Kit No. 336771---757
Part No. Description Quantity
336771--- 707 HX & Panel Assy. 1
FAW5808B Screw 59
336828--- 401 Gasket 2
336839--- 404 Gasket, Coll Box 1
336803--- 407 Cell Panel Insulation 1
AL90AZ173 Screw 12
IIK---336771--- 04 Instructions 1
Kit No. 336771---758
Part No. Description Quantity
336771--- 708 HX & Panel Assy. 1
FAW5808B Screw 43
336828--- 401 Gasket 2
336839--- 401 Gasket, Coll Box 1
336803--- 401 Cell Panel Insulation 1
AL90AZ173 Screw 12
IIK---336771--- 04 Instructions 1
Kit No. 336771---759---CBP
Part No. Description Quantity
336771--- 709 HX & Panel Assy. 1
FAW5808B Screw 61
336828--- 401 Gasket 2
336839--- 404 Gasket, Coll Box 1
336803--- 408 Cell Panel Insulation 1
AL90AZ173 Screw 12
IIK---336771--- 04 Instructions 1
Kit No. 336771---761
Part No. Description Quantity
336771--- 711 HX & Panel Assy. 1
FAW5808B Screw 51
336828--- 401 Gasket 2
336839--- 403 Gasket, Coll Box 1
336803--- 410 Cell Panel Insulation 1
AL90AZ173 Screw 12
IIK---336771--- 04 Instructions 1
Kit No. 336771---763
Part No. Description Quantity
336771--- 703 HX & Panel Assy. 1
FAW5808B Screw 51
336828--- 401 Gasket 2
336839--- 402 Gasket, Coll Box 1
336803--- 403 Cell Panel Insulation 1
AL90AZ173 Screw 12
336839--- 403 Gasket, Coll Box 1
336803--- 410 Cell Panel Insulation 1
336839--- 401 Gasket, Coll Box 1
336803--- 402 Cell Panel Insulation 1
IIK---336771--- 04 Instructions 1
Kit No. 336771---764
Part No. Description Quantity
336771--- 704 HX & Panel Assy. 1
FAW5808B Screw 53
336828--- 401 Gasket 2
336839--- 402 Gasket, Coll Box 1
336803--- 404 Cell Panel Insulation 1
AL90AZ173 Screw 12
336839--- 403 Gasket, Coll Box 1
336803--- 405 Cell Panel Insulation 1
IIK---336771--- 04 Instructions 1
Table 2 – Where Used
Input Casing Width Kit Number
40,000 14-3/16 (360) 336771-758
17-1/2 (445)
60,000
14-3/16 (360) 336771-752-CBP
17-1/2 (445) 336771-763
21 (533) 336771-761
80,000 17-1/2 (445) 336771-764
21 (533)
100,000 21 (533) 336771-756
120,000 24-1/2 (662) 336771-757
140,000 24-1/2 (662) 336771-759---CBP
INSTALLATION
Unit Shut Down
1. Set room thermostat to lowest setting or “OFF.”
2. Disconnect power at external disconnect, fuse or circuit
breaker.
3. Turn off gas at external shut--off or gas meter.
4. Remove outer doors and set aside.
5. Turn electric switch on gas valve to OFF.
Vent Pipe Removal
NOTE: It will be necessary to remove the vent pipe from the
furnace in order to remove the heat exchanger.
1. Support the vent pipe as close to the furnace as possible to
prevent damage to the vent system.
2. Cut vent pipe with a hacksaw and move the remaining vent
pipe out of the way. Secure the vent pipe if necessary.
3. Loosen both clamps at the vent pipe support attached to fur-
nace casing.
4. Loosen clamp for the vent pipe at vent elbow on the inducer
assembly. See Fig. 1.
5. Remove remaining vent pipe through the furnace casing
and set aside.

3
Inducer Mounting Screw
Pressure Switch
Inducer Mounting Screw
Remove Vent Elbow
Vent Elbow Clamp
Remove Tube(s) from
Standoffs
Inducer Mounting Screw
Inducer Mounting Screw
Pressure Switch
Mounting Screw
A11361
Fig. 1 -- Loosen Vent Pipe Clamp
Manifold Removal / Burner Box Removal
NOTE: Use a back--up wrench on the gas valve to prevent the
valve from rotating on the manifold or damaging the mounting to
the burner box. See Fig. 2.
1. Disconnect the gas pipe from gas valve and remove pipe
from the furnace casing.
2. Disconnect the connector harness from gas valve (Modulat-
ing only) or remove individual wires from terminals on gas
valve (All other models).
3. Disconnect the wires from gas valve, flame sensor and hot
surface igniter.
4. Remove wires from both roll--out switches.
UNIT OPERATION HAZARD
Failure to follow this caution may result in improper furnace
operation or failure of furnace.
Label all wires prior to disconnection when servicing controls.
Wiring errors can cause improper and dangerous operation.
CAUTION
!
5. Support the manifold and remove the 4 screws that secure
the manifold assembly to the burner box and set aside.
Note the location of the green and yellow ground wire for
reassembly later.
6. Support the burner box assembly and remove the screws
that attach the burner box to the heat exchanger cell panel.
7. Set the burner box assembly aside.
Pressure Switch Removal
NOTE: There are two types of pressure switches. The modulating
pressure switch assembly has three pressure switches. Two are
side--by--side with the third switch mounted to the back of one of
the switches.
All other furnaces have two pressure switches mounted
back--to--back.
The tube for the front pressure switch connects the switch to the
port on the collector box. For PSC inducers only, the tube for the
switch mounted on the back connects the switch to the port on the
inducer assembly.
1. Remove the front pressure switch tube from the port on the
collector box. See Fig. 1.
2. Disconnect the pressure switch harness (modulating only)
from the main wiring harness or remove the individual
wires from the front pressure switch (non--modulating).
Not the location of the wires for reassembly.
A11443
Fig. 2 -- Burner Assembly / Manifold Assembly / Gas Valve
3. Remove the screws that attach the pressure switch assembly
to the inducer.
4. Remove the back pressure switch tube that connects to the
inducer assembly.
5. Remove the wires from the back pressure switch. Note the
location of the wires for reassembly. (Non--modulating).
6. If the relief tube for the condensate trap is routed across the
inducer assembly, remove the tube from the port on the
collector box and from the stand--offs on the inducer and
move the tube aside.
7. Set the pressure switches aside.
Inducer Assembly Removal
1. Remove the wires that connect the main wiring harness to
the inducer motor harness.
2. Remove the screws from the tabs on inducer assembly that
secures the inducer to the collector box. Note there is one
mounting tab directly under the vent elbow.
3. Remove the inducer assembly and set aside.
4. To avoid double gasketing and leakage, check to make sure
the drain gaskets for the inducer and the inducer outlet gas-
ket are not still attached to the collector box.
5. Remove any remaining gaskets from the collector box and
discard.
Condensate Drain and Trap Removal
NOTE: If the condensate trap is removed, a new gasket between
the trap and collector box is required. Verify a condensate trap
gasket is included in the service kit or obtain one from your local
distributor. See Fig. 1 and Fig. 7 .
1. Disconnect external drain from condensate drain elbow or
drain extension pipe inside the furnace and set aside.
2. Disconnect the condensate trap relief hose from collector
box port and the molded retainer clips on the inducer hous-
ing.
NOTE: If condensate trap has a heat pad attached to the trap, trace
the wires for the pad back to the connection point and disconnect
the wires for the heat pad.
3. Remove the screw that secures the condensate trap to the
collector box, remove the trap and set aside.
4. Remove the trap gasket from the collector box if it did not
come off when the trap was removed.
5. Discard the old trap gasket.
6. Rinse condensate trap in warm water until trap is clean.

4
J−BOX
MOUNTING
SCREWS
J−BOX
MOUNTING
BRACKET
GROUND
SCREW
J−BOX COVER
J-BOX
LOCATIONS
A11299
Fig. 3 -- J--Box Removal / Installation
7. Clean relief port on Condensate Trap with a thin wire or
paper clip, rinse with warm water and set aside.
8. Flush condensate lines with warm water.
9. Shake trap dry.
Remove J--box and Main Harness
1. Remove the screw that secures the J--box cover to the J--box
bracket. See Fig. 3.
2. Disconnect the field wiring from the factory wiring and re-
move the ground wire from the green ground screw on the
J--box bracket.
3. Remove factory wiring from the J--box.
4. Disconnect the factory wires from the main limit switch.
5. Remove the screw that secures the door switch to the
blower shelf and the blower shelf door bracket. Remove
the screws from the blower shelf door bracket, and set the
bracket aside.
6. Remove main harness from the slot in the blower shelf.
Collector Box Removal
1. Remove the screws that secure the collector box to the heat
exchanger cell panel and set aside. See Fig 4.
2. Remove collector box gasket and discard.
3. Flush out the collector box with warm water including the
tube ports. Clean tube ports on collector box with a thin
wire or paper clip, rinse with warm water and set aside.
Collector Box Assembly
Gasket (2)
Plug, Drain (4) Adhesive to Face
Collector Box Assembly
A11412
Fig. 4 -- Collector Box Removal / Installation
Heat Exchanger Assembly Removal
CUT HAZARD
Failure to follow this caution may result in personal injury.
Sheet metal parts may have sharp edges or burrs. Use care and
wear appropriate protective clothing and gloves when
handling parts and servicing furnaces.
CAUTION
!
1. Remove the screws that attach the filler plate to the bottom
edge of the condensing heat exchanger assembly and cas-
ing.
2. Remove screws that secure the heat exchanger assembly to
the heat exchanger mounting brackets.
3. Pull assembly out of casing until the back edge of the heat
exchanger assembly is resting on the front edge of the
blower shelf.
4. Lift the heat exchanger assembly out of the casing and set
aside.
Remove Coupling Box
1. Remove the screws that secure the finger baffle from the
Coupling Box Cover. See Fig. 5.
2. Remove the screws that secure the Coupling Box Cover to
the rear of the Heat Exchanger Assembly.
3. Starting at the upper beveled edge of the coupling box, use
a putty knife or gasket scraper to get between the coupling
box cover and the Primary Cell Outlet panel to break the
silicone seal between the parts.
4. Pry upwards with the putty knife as you move around the
Coupling Box cover.
5. Once the Coupling Box cover is sufficiently loosened, re-
move the coupling box cover from the rear of the Heat Ex-
changer Assembly. See Fig. 6.
Separate Primary and Condensing Heat Ex-
changers
1. Remove the screws that attach the condensing heat ex-
changer assembly to the primary cell outlet panel and re-
move the screws that attach the condensing heat exchanger
outlet panel to the primary inlet panel.
2. Gently use a putty knife or gasket scraper to get between the
primary cell inlet panel and condensing heat exchanger if it
is needed to break the seal between the parts.
3. Repeat the procedure at the primary cell outlet panel and
containment plate attached to the inlet of the secondary heat
exchanger.

5
Remove Primary and Condensing Heat Exchanger
NOTE: The primary heat exchanger assembly is factory--
assembled at primary cell attachment plate and the primary rear cell
outlet panel. The individual heat exchanger cells cannot be
removed in the field and are replaced as one assembly.
1. Remove screws that attach the sidewall baffles to the heat
exchanger cell panel. See Fig. 8.
NOTE: The front edge of the sidewall baffle has a slot that
engages a tab on the primary cell panel. See Fig. 8.
2. Avoid damaging the cell panel insulation by pulling the
sidewall baffle outward from the rear of coupling box, then
pull the baffle backward to slide the baffle off of the locator
tab on the cell panel.
3. Repeat the procedure for the opposite side baffle.
4. Remove the screws around each burner inlet opening that
attaches the heat exchanger cell panel to the primary inlet
plate of the primary heat exchanger assembly.
5. If not removed already, remove the screws that attach the
primary cell panel to the front of condensing heat exchanger
section.
6. Separate the Primary Heat Exchanger from the Condensing
Heat Exchanger.
7. Remove the primary cell panel from the primary cell inlet
plate and set aside.
BOX COVER
CELL PANEL
A11413
Fig. 5 -- Heat Exchanger Removal / Installation

6
BEGIN RE--ASSEMBLY
Install Heat Exchanger Primary Cell Panel
1. Align the primary cell panel with the primary inlet plate of
heat exchanger assembly.
2. Avoid damaging the cell panel insulation during alignment.
3. Insert the screws around each burner inlet opening that at-
taches the heat exchanger cell panel to the primary inlet
plate of the primary heat exchanger assembly.
Attaching Primary and Condensing Heat
Exchangers
1. Align the bottom edge primary cell outlet panel with the top
edge of the condensing heat exchanger assembly, and align
the top edge of the condensing heat exchanger outlet panel
with the bottom edge of the primary cell inlet panel.
2. The orange foam gasket must be between the primary cell
outlet panel and the containment plate that is attached to the
condensing heat exchanger. The white fiber gasket or equi-
valent must be between the primary cell inlet panel and the
condensing heat exchanger outlet panel.
3. Insert all the screws, except the outboard screws in the
primary outlet panel, to secure the primary heat exchanger
panels to the condensing heat exchanger panels (front and
back). See Fig. 5.
4. Remove the screws used to temporarily hold the Contain-
ment Plate in place.
Install Coupling Box Cover/Finger Baffles
1. Apply a 1/4” bead of low adhesion silicone (white) to the
coupling box cover in the pattern shown in Fig. 9.
2. Align the Coupling Box Cover over the rear of the Heat Ex-
changer Assembly. See Fig. 5 and Fig. 6.
3. Install the screws that secure the bottom edge and sides of
the Coupling Box to the Heat Exchanger Assembly.
4. Align the Finger Baffles along the top edge of the Coupling
Box Cover. See Fig. 5.
5. Install the screws for the Finger Baffles and the remaining
screws for the top edge of the Coupling Box Cover.
Install Sidewall Baffles
1. Avoid damaging the cell panel insulation by inserting the
sidewall baffle inward from the rear of coupling box to the
indexing tab on the primary cell panel then align the baffle
with the coupling box cover.
Insert the slot on the sidewall baffle over the tab on the
primary cell panel. See Fig. 6.
NOTE: The front edge of the sidewall baffle has a slot that
engages a tab on the primary cell panel.
A11414
Fig. 6 -- Sidewall Baffle Removal / Installation -- Rear View
2. Insert the screws that attach the sidewall baffle to the
primary cell panel.
3. Align the rear edge of the baffle with the screw holes in the
coupling box cover.
4. Insert the screws that attach the sidewall baffles to the coup-
ling box.
Heat Exchanger Assembly Installation
1. Lift the heat exchanger assembly and set the rear of the as-
sembly on the blower deck.
2. Slide the heat exchanger onto the support rails in the fur-
nace casing.
3. Raise the rear of the heat exchanger and set the bottom of
the sidewall baffles on top of the support rails in the blower
deck.
4. Slide the heat exchanger assembly into the casing, making
sure the bottom edge of the sidewall baffle slides into the
engagement tab on the support rails.
NOTE: Be sure cell panel insulation is folded over the top flange
of the primary cell inlet panel so that when the heat exchanger is
fully installed, the insulation seals between the top plate and the top
flange of the cell panel.
NOTE: Be sure the cell panel insulation is visible on both sides of
the heat exchanger cell panel so that when the heat exchanger is
fully installed, the insulation seals between the cell panel and the
mounting brackets. If any insulation is not visible, pull the heat
exchanger forward, adjust the insulation and reinstall so that the
cell panel is properly sealed to the top plate and to the mounting
brackets.
5. Continue to slide the heat exchanger assembly backward in-
to the casing until the primary cell panel is flush with the
mounting brackets on the side of the casing.
6. Align the primary cell panel with the mounting brackets.
7. Insert the screws that attach the primary cell panel to mount-
ing brackets on the casing.
8. Align the filler plate to the bottom edge of the condensing
heat exchanger assembly.
9. Secure the filler plate to the condensing heat exchanger and
casing.
Collector Box Installation
1. Verify old collector box gasket has been removed from heat
exchanger. See Fig 7.
2. Remove adhesive backing from collector box gasket and
align gasket on the collector box.
3. Attach the gasket to the collector box.
4. Remove the adhesive backing from the condensate trap gas-
ket.
5. Attach the gasket over the drain outlets on the collector box.
6. Repeat the procedure for the drain outlet.
NOTE: There is a slot on each side of the front panel of the
condensing heat exchanger. The collector box has alignment tabs
on the back that fit into the slots on the condensing heat exchanger
panel.
7. Align the tabs on the collector box to the slots on the
condensing heat exchanger panel.
8. With the collector box fully seated against the condensing
heat exchanger cell panel, install the screws through the
collector box.
9. Tighten the screws in an alternating pattern around the
collector box. Do not over--tighten.

7
REMOVE OLD GASKET
APPLY NEW GASKET TO COLLEC-
TOR BOX BEFORE RE-INSTALLING
CONDENSATE TRAP
CONDENSATE TRAP
A11442
Fig. 7 -- Collector Box Gasket Condensate Trap
Install J--box and Main Harness
1. Insert grommet for main harness in the slot in the blower
shelf.
2. Align the door switch to the blower shelf.
3. Align and install door bracket to the front edge of the
blower shelf and secure the door switch during upper door
bracket installation.
4. Connect the field wiring from the factory wiring and attach
the ground wire to the green ground screw on the J--box
bracket.
5. Attach the J--box cover to the J--box bracket.
6. Install the screw to secure the J--box cover to the bracket.
7. Connect the factory wires to the main limit switch.
Install the Condensate Trap and Drain
NOTE: If the condensate trap is removed, a new gasket between
the trap and collector box is required. Verify a condensate trap
gasket is included in the service kit or obtain one from your local
distributor.
1. Align the trap with the drain outlet on the collector box.
2. Secure the trap to the collector box with the screw.
3. Connect the condensate trap relief tube from collector box
port and insert the tube into the molded retainer clips on the
inducer housing.
4. Insert the condensate drain elbow through the casing until it
is properly seated. Or, connect the drain elbow to the drain
extension pipe and route the pipe behind the inducer.
5. Connect the drain elbow to the condensate trap.
NOTE: If condensate has a heat pad attached to the trap, trace the
wires for the pad back to the connection point and connect the
wires for the heat pad.
Inducer Assembly Installation
1. Verify any remaining gaskets on the collector box are re-
moved and discarded.
2. Verify the inducer assembly has gaskets on the drain stubs
and at the inducer inlet.
3. Verify the choke plate is installed on the inlet opening of the
inducer.
4. Align the tabs on inducer assembly to the brass inserts on
the collector box.
5. Insert the mounting screws through the tabs to secure the
inducer to the collector box. Remember there is a mounting
tab located under the vent elbow.
6. Connect the inducer leads from the main wiring harness to
the inducer motor harness.
Pressure Switch Installation
NOTE: There are two types of pressure switches. The modulating
pressure switch assembly has three pressure switches.
Two are side-by-side with the third switch mounted to the back of
one of the switches.
All other furnaces have two pressure switches mounted
back--to--back.
The tube for the front pressure switch connects the switch to the
port on the collector box. The tube for the switch mounted on the
back connects the switch to the port on the inducer assembly.
1. Connect the wires to the back pressure switch.
2. Connect the tube for the back pressure switch to the inducer
assembly.
3. Connect the tube for the front pressure switch to the port on
the collector box.
4. Attach the pressure switch assembly to the inducer.
5. Connect the pressure switch harness (modulating only) to
the main wiring harness or attach the individual wires to the
pressure switch (non--modulating).
6. If necessary, route the pressure switch tubing for the front
pressure switch through the stand--off on the inducer as-
sembly.
7. If necessary, route the condensate trap relief tubing through
the stand--off on the inducer assembly. Reconnect tubing to
the ports on the condensate trap and collector box.
Burner Box/Manifold Installation
1. Support the burner box assembly and install the screws that
attach the burner box to the heat exchanger cell panel.
2. Align the orifices in the manifold assembly with the support
rings on the end of the burner.
3. Insert the orifices in the support rings of the burners. Mani-
fold mounting tabs should fit flush against the burner box
NOTE: If manifold does not fit flush against the burner box, the
burners are not fully seated forward. Remove the manifold and
check burner positioning in the burner box assembly.
4. Attach the green/yellow wire and ground terminal to one of
the manifold mounting screws.
5. Install the remaining manifold mounting screws.
6. Connect the wires to both roll--out switches.
7. Connect the wires to the flame sensor and hot surface ig-
niter.
8. Connect the connector harness from gas valve (Modulating
only) or attach the individual wires to the terminals on gas
valve (All other models).

8
NOTE: Use only propane--resistant pipe dope. Do not use Teflon
tape.
9. Insert the gas pipe through the grommet in the casing. Ap-
ply a thin layer of pipe dope to the threads of the pipe and
thread the pipe by into the gas valve.
NOTE: Use a back--up wrench on the gas valve to prevent the
valve from rotating on the manifold or damaging the mounting to
the burner box.
10. With a back--up wrench on the inlet boss of the gas valve,
finish tightening the gas pipe to the gas valve.
11. Turn gas on at electric switch on gas valve.
12. Turn power on at external disconnect, fuse or circuit break-
er.
Vent Pipe Installation
1. Insert the vent pipe through the intended vent opening of
the furnace casing and insert into the outlet of the inducer
vent elbow.
2. Tighten the clamp for the vent pipe at vent elbow on the
inducer assembly.
3. Align the remaining vent pipe system to the vent pipe in the
furnace casing.
4. Solvent cement the pipes as required for the type of material
used.
5. Tighten both clamps at the vent pipe support attached to
furnace casing.
Unit Checkout
FIRE OR EXPLOSION HAZARD
Failure to follow this warning could result in personal injury,
death and/or property damage.
Never purge a gas line into a combustion chamber. Never test
for gas leaks with an open flame. Use a commercially available
soap solution made specifically for the detection of leaks to
check all connections. A fire or explosion may result causing
property damage, personal injury or loss of life.
!WARNING
1. Set thermostat to “OFF”.
2. Turn on power at external disconnect, fuse or circuit break-
er.
3. Turn on gas at external shut--off or gas meter.
4. Check for gas leaks with a commercially available soap
solution made specifically for the detection of leaks.
5. Manually close blower door switch.
6. Initiate component test through circuit board by referring to
“Component Test” on status code label on blower access
door for complete test sequence information.
7. If any status codes are flashed, refer to status code label on
unit blower door.
8. Turn thermostat fan switch to “ON”, “Continuous” or jump-
er R to G terminals at furnace control board.
9. Check for air leakage around cell panel. It may be necessary
to remove heat exchanger assembly and top gasket between
cell panel and furnace casing top plate. Re--install and re--
check for blower air leaks.
10. Remove jumper(s) or set thermostat fan to “Auto” or
“OFF”.
11. Release blower door switch.
12. Install blower access door.
13. Set thermostat to call for heat.
14. Allow unit to initiate a complete call for heat cycle.
15. Check for air leakage around collector box. A whistling
noise may indicate air leak in collector box seal.
NOTE: If there is a severe air leak in the collector box seal,
pressure switch may not close or will re--open, resulting in no
ignition or erratic burner operation.
NOTE: Heat Exchanger failure may have been caused by one or
more of the following conditions. As part of the system check--out,
verify that the following conditions are not affecting the operation
of the furnace:
SShort Cycling--Defective thermostat: Incorrect thermostat
anticipator setting, dirty filter or over--sized furnace.
SUnder firing/low Btu input: Set manifold pressure and verify
firing rate as shown on rating plate by clocking the gas meter.
SOver--firing/high Btu input: Set manifold pressure and verify
firing rate as shown on rating plate by clocking the gas meter.
SLow temperature rise: Set unit for correct temperature rise range
as shown on unit rating plate.
SContaminated combustion air: Remove contaminates or provide
ample fresh air for combustion.
SExcessive amounts of outside ventilation air: Return air
temperature cannot be below 60 degrees F for extended periods of
time.
SIncorrect venting or termination: Recirculation of products of
combustion into the combustion air pipe can damage the furnace.
Verify proper venting and vent termination per installation
instructions. For additional information, and a complete sequence
of furnace operation, refer to furnace Installation, Start--Up and
Operating Instructions.
16. After System Check--out is complete, set thermostat below
room temperature.
17. Verify that burner shuts down and blower completes selec-
ted off delay time.
18. Verify furnace operates properly and set thermostat to de-
sired room temperature.
19. Re--install outer door.

9
A11438
Fig. 8 -- Heat Exchanger Panel Assembly

10
SILICONE SEALER
A11438
Fig. 9 -- Collector Box Sealant Application
Copyright 2012 CAC / BDP D7310 W. Morris St. DIndianapolis, IN 46231 Edition Date: 08/12
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
Catalog No: IIK---336771---04
Replaces: IIK---336771--- 03