Replacement Aluminized Primary Heat Exchanger: Installation Instructions
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
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2. Disconnect the connector harness from gas valve (Modulating 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.
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
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.
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
NOTE:
See
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 and 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 inducer housing.
7. Remove any adhered gaskets from the front of the collector box.
Verify old gaskets are reusable or obtain new gaskets from the
distributor. Apply gaskets to the rear of the inducer 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
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 housing.
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. 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
2. Disconnect the field wiring from the factory wiring and remove 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
.
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.
CAUTION
!
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.
