[ericzy01]

From last night, the furnace (Amana Air command 80) stopped firing when the thermostat calls for heat, the fan kept on blowing air. The LED on control module (White Rodgers 50E47-843, which replaced with original one 2 yrs ago) is always OFF. In the manual, there is two different clues:
1. OFF: Internal Failure.
2. After calling for heat, yellow LED should light for 2 seconds, if no, check Low Voltage to module (TH-TR). If no voltage:Check Limit Switches, check vent pressure switch (if used).

Should I check limit/pressure switch, or replace control module?

Thanks!
Eric

 

[ben's plumbing]

From last night, the furnace (Amana Air command 80) stopped firing when the thermostat calls for heat, the fan kept on blowing air. The LED on control module (White Rodgers 50E47-843, which replaced with original one 2 yrs ago) is always OFF. In the manual, there is two different clues:
1. OFF: Internal Failure.
2. After calling for heat, yellow LED should light for 2 seconds, if no, check Low Voltage to module (TH-TR). If no voltage:Check Limit Switches, check vent pressure switch (if used).

Should I check limit/pressure switch, or replace control module?

Thanks!
Eric

check the limit and pressure switch 1st..... make sure they are working ..ben sr