Instruction manual

Part number 550-142-056/0411
85
GWC gas-fired water boiler — Boiler Manual
Troubleshooting (continued)
CHART 7
LIMIT light flashing and POWER light on steady
Electrical shock hazard — Wherever you see TURN OFF POWER, follow the instructions. Failure to follow
instructions could result in severe personal injury, death or substantial property damage.
• Remove SENSOR plug from receptacle on IBC (Figure 89, page 76, Item 6).
• Then re-insert.
Does LIMIT light still flash?
No Yes
• Replace sensor and harness.
Does LIMIT light still flash?
No Yes
• Boiler may now be operating correctly. Verify per normal
sequence of operation (Figure 71, page 63).
• Replace IBC.
• Retest.
• This is NOT a lockout mode. The IBC should only be signal-
ing that the water temperature sensor is either shorted or
there is an open circuit across the sensor terminals.
• This situation is usually corrected by replacing the sensor,
as described below.