Carrier 336774-752-CPB User manual

1
336774---752---CBP thru
336774---759---CBP
336774---762---CBP thru
336774---770---CBP
336774---772---CBP thru
336774---778---CBP
Installation Instructions
CONDENSING HEAT EXCHANGER KIT
F O R U S E W I T H 3 5 --- I N . T A L L
HIGH EFFICIENCY
CONDENSING GAS FURNACE
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 Condensing Heat
Exchanger Kit, Part No. 336774--752 thru --759, 336774--762
thru --770 and 336774--772 thru --778 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.
There are two different RTV sealants used on this assembly and are
needed before starting the assembly.
The low adhesion sealant used on the Coupling Box cover is
Novaguard RTV 400--900t(P/N 680002).
If the high adhesion sealant is used, also use a releasing agent such
as cooking spray (must not contain corn oil, canola oil,
halogenated hydrocarbons nor aromatic contents to prevent
inadequate seal from occuring). Novaguard 400--303 RTV (P/N
680001), G.E. 162, G.E. 6702, or Dow--Corning 738 are approved
high adhesion silicone.
DO NOT substitute any other type of low or high adhesion RTV
sealant.

2
DESCRIPTION AND USAGE
Use this Condensing Heat Exchanger kit to replace a failed
condensing heat exchanger. This Condensing 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. 336774---752, ---758, ---762, ---772
Description Quantity
HX & Panel Assy. 1
Containment Plate 1
Screw 43
Gasket 2
Coll. Box Gasket 1
Screw 8
Instructions 1
Kit No. 336774---753, ---754, ---755, ---763, ---764, ---765, ---773,
---774, ---775, ---776
Description Quantity
HX & Panel Assy. 1
Containment Plate 1
Screw 49
Gasket 2
Coll. Box Gasket 1
Screw 10
Instructions 1
Kit No. 336774---756, ---766, ---767, 769, ---777
Description Quantity
HX & Panel Assy. 1
Containment Plate 1
Screw 51
Gasket 2
Coll. Box Gasket 1
Screw 12
Instructions 1
Kit No. 336774---757, ---759, ---768, ---770, ---778
Description Quantity
HX & Panel Assy. 1
Containment Plate 1
Screw 59
Gasket 2
Coll. Box Gasket 1
Screw 12
Instructions 1
Table 2 – Where Used
KIT NUMBER SERIES INPUT
BTUH
CASING
W I D T H --- I N
(MM)
336774--- 752--- CBP A40,000 14 3/16 (360)
336774--- 753--- CBP A40,000 17 1/2 (445)
336774--- 754--- CBP A60,000 17 1/2 (445)
A80,000
336774--- 755--- CBP A80,000 21 (533)
336774--- 756--- CBP A60,600 21 (533)
A100,000
336774--- 757--- CBP A120,000 24 1/2 (622)
336774--- 758--- CBP A60,000 14 3/16 (360)
336774--- 759--- CBP A140,000 24 1/2 (622)
336774--- 769--- CBP A100,000 21 (533)
336774--- 770--- CBP A120,000 24 1/2 (622)
140,000
336774--- 762--- CBP B40,000 24 1/2 (622)
B60,000
336774--- 763--- CBP B40,000 17 1/2 (445)
336774--- 764--- CBP B60,000 17 1/2 (445)
336774--- 765--- CBP B80,000 17 1/2 (445)
336774--- 766--- CBP B80,000 21 (533)
336774--- 767--- CBP B100,000 21 (533)
336774--- 768--- CBP B120,000 24 1/2 (622)
Table2--WhereUsed(Con’t.)
KIT NUMBER SERIES INPUT
BTUH
CASING
W I D T H --- I N
(MM)
336774--- 772--- CBP
C26,000 14--- 3/16
(360)
C40,000
C60,000
336774--- 773--- CBP C40,000
17 1/2 (445)336774--- 774--- CBP C60,000
336774--- 775--- CBP C80,000
336774--- 776--- CBP C80,000 21 (533)
336774--- 777--- CBP C100,000
336774--- 778--- CBP C120,000 24--- 1/2 (622)
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.
5. Remove remaining vent pipe through the top of the furnace
casing and set aside.
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. 3.
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 rollout 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.

3
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. 3.
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.
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
!
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. (PSC only).
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
NOTE: See Fig. 3 for inducer assembly detail and component
locations.
1. Remove the door bracket from the front edge of the blower
shelf.
2. Remove the wires that connect the main wiring harness to
the inducer motor harness.
3. Remove the condensate trap relief tube from the port on the
collector box an the stand--offs on the inducer housing.
4. 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.
5. Remove the inducer assembly and set aside.
6. To avoid double gasketing and leakage, check to make sure
the drain gaskets for the inducer and the inducer inlet gasket
are not still attached to the collector box.
7. Remove any adhered gaskets from the front of the collector
box. Verify old gaskets are re--usable or obtain new gaskets
from the distributor. Apply gaskets to the rear of the induc-
er housing and set aside for reassembly later.
Condensate Drain and Trap Removal
NOTE: If the condensate trap is removed, a new gasket between
the trap and collector box is required. Obtain one from your local
distributor. See Fig. 1 and Fig. 3.
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 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. Rinse condensate trap in warm water until trap is clean.
5. Clean relief port on Condensate Trap with a thin wire or
paper clip, rinse with warm water and set aside.
6. Flush condensate lines with warm water.
7. 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. 2.
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.
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.
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 furnace casing. Do not remove the screws around the
burner inlets that attaches the primary inlet panel to the inlet
plate of the primary heat exchanger.
3. Pull assembly out of casing until the back edge of the heat
exchanger 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. 4.

4
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.
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. 6.
NOTE: The front edge of the sidewall baffle has a slot that
engages a tab on the primary cell panel. See Fig. 6.
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. Separate the Primary Heat Exchanger from the Condensing
Heat Exchanger.
5. Discard failed Condensing Heat Exchanger assembly.
Turbulator Removal
NOTE: The turbulators are factory--installed in a replacement
condensing heat exchanger. It is not necessary to remove them to
replace a condensing Heat Exchanger Assembly. If it is necessary
to remove the turbulators, perform the following steps:
1. Bend the end of turbulator strip that holds it inside the sec-
ondary heat exchanger tube straight.
NOTE: Use caution when removing the turbulator strips. Do not
bend, twist kink or flatten the turbulator strip. A damaged
turbulator strip must be replaced with the identical type of
turbulator strip used with the furnace. Do not use a turbulator strip
from a different model family of furnaces. Efficiency, reliability or
unit operation may be affected.
2. Pull the turbulator strip outward from the tube.
3. Repeat the step for each turbulator.
4. Wipe each turbulator off with a clean, soft cloth.
BEGIN RE--ASSEMBLY
Turbulator Installation
NOTE: The turbulators are factory--installed in a replacement
condensing heat exchanger. If the turbulators were removed for
cleaning, re--install the turbulators as follows:
1. Make sure that one end to the turbulator strip is bent 90 de-
grees.
NOTE: Use caution when installing the turbulator strips. Do not
bend, twist kink or flatten the turbulator strip. A damaged
turbulator strip must be replaced with the identical type of
turbulator strip used with the furnace. Do not use a turbulator strip
from a different model family of furnaces. Efficiency, reliability or
unit operation may be affected.
2. Push the straight end of turbulator strip forward into the sec-
ondary heat exchanger tube until the angled end is against
the edge of the tube.
3. Repeat the step for each turbulator.
4. Bend the straight end of the turbulator strip over 90 degrees
to hold the turbulator in the secondary heat exchanger tube.
Install Containment Plate
NOTE: Both the containment plate and secondary heat exchanger
panel surfaces must be clean and dry. All loose or residual sealant
must be removed from the mating surfaces.
NOTE: Do not use a releasing agent on the Containment Plate or
Heat Exchanger Assembly.
1. Apply a 3/16” wide bead of high adhesion (grey) silicone,
Novaguard 400--303 RTV, or equivalent as noted on page 1,
around the Containment Plate as shown in Fig. 7. Note the
orientation of the plate in Fig. 7
2. Align the containment plate as shown in Fig. 7.
3. Temporarily hold the containment plate in place by in-
stalling one screw through the hole on each side of the con-
tainment plate.
NOTE: After the primary heat exchanger assembly is attached to
the secondary heat exchanger, these screws will be removed to
allow the coupling box cover to be installed.
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 temporarily at-
tached to the condensing heat exchanger. The white fiber
gasket or equivalent 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. 7.
2. Align the Coupling Box Cover over the rear of the Heat Ex-
changer Assembly. See Fig. 5 and Fig. 4.
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.
6. Align the sidewall baffles to the heat exchanger cell panel.
See Fig. 4 and Fig. 6.
NOTE: The front edge of the sidewall baffle has a slot that
engages a tab on the primary cell panel.
7. 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.
8. Secure the Sidewall Baffles with the screws.
Install Sidewall Baffles
1. Insert the slot on the sidewall baffle over the tab on the
primary cell panel. See Fig. 6.
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.

5
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 is reusable or obtain a new
gasket from the distributor (preferred).
2. Obtain new condensate trap gasket from distributor and in-
stall.
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.
3. Align the tabs on the collector box to the slots on the
condensing heat exchanger panel.
4. With the collector box fully seated against the condensing
heat exchanger cell panel, install the screws through the
collector box.
5. Tighten the screws in an alternating pattern around the
collector box. Do not over--tighten.
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. 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 front of the collector
box are removed.
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, rout 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 rollout switches.

6
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).
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.
ELECTRICAL OPERATION HAZARD
Failure to follow this warning could result in personal injury
or death.
Blower door switch opens 115--v power to control. No
component operation can occur unless switch is closed.
Caution must be taken when manually closing this switch for
service purposes.
!WARNING
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.

7
REMOVE OLD GASKET
APPLY NEW GASKET TO COLLEC-
TOR BOX BEFORE RE-INSTALLING
CONDENSATE TRAP
CONDENSATE TRAP
A11442
Fig. 1 -- Collector Box Gasket Condensate Trap
J−BOX
MOUNTING
SCREWS
J−BOX
MOUNTING
BRACKET
GROUND
SCREW
J−BOX COVER
J-BOX
LOCATIONS
A11299
Fig. 2 -- J--Box Removal / Installation
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. 3 -- Loosen Vent Pipe Clamp
A11414
Fig. 4 -- Sidewall Baffle Removal / Installation -- Rear View

8
(SEE DETAIL F)
(SEE DETAIL G)
DETAIL G
DETAIL F
CELL PANEL
HEAT EXCHANGER
COUPLING BOX COVER
A13103
Fig. 5 -- Condensing Heat Exchanger Removal / Installation

9
A11438
Fig. 6 -- Heat Exchanger Panel Assembly

10
SILICONE SEALER
SILICONE SEALER
A11416
Fig. 7 -- Containment Plate and Collector Box Sealant Application
Copyright 2016 CAC / BDP D7310 W. Morris St. DIndianapolis, IN 46231 Edition Date: 09/16
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
Catalog No: IIK---336774---08
Replaces: IIK--- 336774--- 07