Advertisement
Remove Tube(s) from
Inducer Mounting Screw
Standoffs
Inducer Mounting Screw
Pressure Switch
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.
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.
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.
Inducer Mounting Screw
Vent Elbow Clamp
Remove Vent Elbow
Inducer Mounting Screw
Pressure Switch
Mounting Screw
A11361
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.
3
A11443
Advertisement
