Table 3-3. Unit Maintenance Troubleshooting Continued
TEST OR INSPECTION
b. Inspect terminals (5) and potting of wires (6 and 7) to PC board.
Reconnect as needed. If
If PC board wires appear
spark is still not observed, replace transformer
defective, forward unit to organizational
4. HEATER BACKFIRES
Step 1. Check igniter assembly. Remove igniter from burner head. Inspect for fouling
and burned electrode (1), End of electrode must be flush with face (2) to
0.010 inch (0.254 mm) underflush.
If badly fouled or burned, replace igniter.
Step 2. Check ignition cable connector for burned spring and damaged connector.
If spring is burned or connector
damaged, replace kitted parts as
described in REMOVE/lNSTALL/
TRANSFORMER AND CABLE,