5
Airflow Conversion
This furnace is factory assembled for right to left airflow. It can be
converted to left to right airflow. The conversion should be made
prior to installing the unit.
IMPORTANT:
■
The sides are identified as the original component side and
the new component side. Steps 1 through 12 (following) refer
to the original component side.
■
Gas leak checking should be performed after the conversion.
See the “Make Gas Connections” section.
1. Disconnect power.
2. Disconnect 3 connectors at the gas control valve and the
strain relief bushing for the cable routed through the burner
access cover.
3. Disconnect the wires from the primary limit control, pressure
switch, and rollout switch.
4. Remove the control box cover (4 screws).
5. Label wires when disconnected with the name of the terminal
on the wiring board where it is connected. Remove the
circulating air blower wires last.
6. Disconnect the combustion blower tubing from the
combustion blower housing.
7. Disconnect the plastic tubing from the pressure tap at the
burner access cover and the gas control valve, leaving all
remaining tubing connected to the pressure switch.
8. Remove the control box and combustion blower, leaving the
safety circuit/combustion blower circuit wiring attached to
the control box (4 screws).
9. Remove the wire channel guard (6 screws). Remove the wire
hanger P-clip located on the lower, center screw.
10. Remove the pressure switch.
11. Remove the primary limit switch.
WARNING
Electrical Shock Hazard
Disconnect power before servicing.
Replace all parts and panels before operating.
Failure to do so can result in death or electrical shock.
1. Burner access panel
2. Pressure tap
3. Pressure switch tubing
4. Blower control board
5. Control box
6. Control box bushing
7. Primary limit switch
8. Rollout switch
9. Wire channel guard
10.Pressure switch
11. Blower wire bushing
12. Blower door interlock switch
13. Circulating air blower access door
14. Combustion blower tubing
15. Combustion blower
16. Manifold cover
17. Gas control valve
18. Igniter wire strain relief bushing
19. PVC collar
20. Sight glass
1
2
3
4
11 12
13
15
16
17
18
19
20
5
6
7
9 10
8
14
Before Conversion (original component side)
