Troubleshooting: Heating Sequence of Operation
NO
HEATING SEQUENCE OF OPERATION
NORMAL HEATING MODE |
|
| ABNORMAL HEATING MODE |
| |||||
|
|
|
|
|
|
|
|
|
|
|
| POWER ON |
|
|
|
|
| ||
|
|
|
| GAS VALVE OFF. COMBUSTION AIR INDUCER OFF. |
| ||||
|
|
|
|
|
|
|
|
| |
|
|
|
|
|
|
| NO | INDOOR BLOWER DELAY OFF. |
|
CONTROL SELF−CHECK OKAY? |
|
| LED #1 ON |
| |||||
|
|
|
|
|
|
|
| LED #2 ON |
|
|
|
|
|
|
|
|
| (RESET CONTROL BY TURNING MAIN POWER OFF.) |
|
|
| YES |
|
|
| NO |
|
| |
|
|
|
|
| POLARITY REVERSED. |
| |||
|
|
|
|
|
|
|
| ||
| IS POLARITY CORRECT? |
|
| LED #1 −− FAST FLASH |
| ||||
|
|
|
|
|
|
|
| LED #2 −− SLOW FLASH |
|
|
| YES |
|
|
|
|
| ||
|
|
|
|
|
|
| NO |
|
|
|
|
|
|
|
|
| IMPROPER GROUND. |
| |
IS THERE A PROPER GROUND? |
|
| LED #1 −− ALTERNATING FAST FLASH |
| |||||
|
| YES |
|
|
|
|
| LED #2 −− ALTERNATING FAST FLASH |
|
|
|
|
| NO |
|
|
|
| |
|
|
|
|
|
|
|
|
| |
|
|
|
|
|
|
| LEDs SIGNAL FAST ALTERNATING FLASH. |
| |
|
| IS VOLTAGE |
|
|
|
|
| ||
|
|
|
|
|
| CONTROL WILL NOT RESPOND TO A CALL FOR |
| ||
|
| ABOVE 90 VOLTS? |
|
|
|
|
| ||
|
|
|
|
| HEATING UNTIL VOLTAGE RISES ABOVE 95 VOLTS. |
| |||
|
|
|
|
|
|
| |||
|
|
|
|
|
|
|
|
|
|
|
| YES |
|
|
|
| NO | GAS VALVE OFF. COMBUSTION AIR INDUCER ON. |
|
|
|
|
| INDOOR BLOWER ON. |
| ||||
ROLLOUT SWITCH CLOSED? |
|
| LED #1 −− ON. LED #2 −− SLOW FLASH. |
| |||||
|
|
|
|
|
|
|
|
| |
|
|
|
|
|
|
|
| SEQUENCE HOLDS UNTIL ROLLOUT SWITCH CLOSES |
|
|
| YES |
|
|
|
| AND POWER IS RESET OR T’STAT IS INTERRUPTED |
| |
|
|
|
|
|
|
|
| FOR MINIMUM OF 1 SECOND. |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| NO | GAS VALVE OFF. COMBUSTION AIR INDUCER ON. |
|
|
| BURNER OFF? |
| INDOOR BLOWER ON HEATING SPEED. |
| ||||
|
|
|
|
| |||||
(Flame sensed without gas valve energized) |
|
| LED #1 −− SLOW FLASH |
| |||||
|
|
| |||||||
|
| YES |
|
|
|
|
| LED #2 −− OFF |
|
|
|
|
|
|
|
|
| ||
|
|
|
|
|
|
|
| ||
|
|
|
|
|
|
|
|
|
|
NORMAL OPERATION:
LED #1 −− SLOW FLASH
LED #2 −− SLOW FLASH
YES
THERMOSTAT CALLS FOR HEAT:
LED #1 −− FAST FLASH
LED #2 −− FAST FLASH
YES
PRIMARY LIMIT SWITCH. CLOSED?
YES
IS COMBUSTION AIR
PRESSURE SWITCH OPEN?
YES
IS COMBUSTION AIR INDUCER
ENERGIZED?
NO |
NO
COMBUSTION AIR INDUCER OFF.
INDOOR BLOWER ON
LED #1 SLOW FLASH RATE
LED #2 −− ON
GAS VALVE OFF.
COMBUSTION AIR INDUCER OFF. INDOOR BLOWER OFF WITH DELAY. LED #1 OFF
LED #2 SLOW FLASH
(Sequence holds until pressure switch opens or thermostat resets control.)
YES
HAS COMBUSTION AIR PRESSURE SWITCH CLOSED IN 2.5 MINUTES?
YES
PRESSURE SWITCH IS IN WATCHGUARD MODE. NO GAS VALVE OFF. COMBUSTION AIR INDUCER OFF.
INDOOR BLOWER OFF WITH DELAY.
LED #1 −− OFF. LED #2 −− SLOW FLASH.
IS
YES
CONTINUED NEXT PAGE
Page 45
