Author Topic: On Call for Heat, Blower and Inducer running together, But No Fire and Flam  (Read 616 times)

I have a Luxaire Gas Furnace High Efficiency , 2 Stage , Model # FL9T100C16UP11C  / Serial # W0C6037901.
when thermostat call for heat ; at the same time blower motor and inducer running together , but no fire at burner ,
error code red flashing shows , high limit switch is open, but i checked is good and i changed with new one , i reset flame roll out , but still blower and inducer running together and no fire and flame.
any body can help me ?

Offline Admin

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If you have verified the limit and other 24V safeties are in fact closed then it seems the control board could be faulty, if the error code says the limit is open.

Normally only the furnace fan would run if there is an open safety.  The fact that the ventor motor is still running seems to also indicate a possible faulty control board.  I'm not 100% sure how that model works but maybe the ventor will still run if a safety is open.

You mentioned resetting the flame rollout.  Did it trip open?

Offline harshal

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chk vent motor temp switch.if its bad then u need tobchange gasket for collector box.they have high temp in there.

Offline walker

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did you determine why the flame roll out was tripped in the first place?  Also check to see that there isnt any open limits on the blower housing or some other limit switch you've missed.

Offline Kriz

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sounds like a faulty control board or, like Walker said, you're missing an open safety somewhere..
Walker already said this but some units have a high limit safety switch located underneath the unit down by the blower motor that opens on high limit and is manually reset.. look down around the blower motor housing for it
Dirty filter/inadequate airflow or heat backing up in the unit will cause this safety to trip

Offline ainsworthCA

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ensure your switches are closing. reading 0v across. don't always use ohms resistance.

you may be missing one limit occasionally there are aux limits.

sometimes the inducer will run when in fault. incase of gas in the flue.

check your wiring

if not its the board