Why does my furnace start and then shut off?

If the furnace starts then shuts off instantly it may be because the flame sensor is not able to identify the flame and the control board will shut off voltage to the gas valve interrupting the heat cycle. You can use a soft abrasive pad to clean the flame sensor.

When does the furnace blower turn on and off?

In normal operation, your furnace blower fan should come on 1.5 to 3 minutes after your thermostat calls for heat and should turn off several minutes after the heating cycle ends. Your blower should run constantly until the heating cycle ends.

How does the fan on and off work on a furnace?

1- FAN OFF: the low temperature at which the furnace blower fan will STOP to prevent blowing cool air onto room occupants. 2- FAN ON: the temperature at which the blower fan will turn ON to begin to deliver heat to the building’s occupied spaces.

Why does my furnace blower wheel keep going out?

Dirty blower wheel: If the filters are left dirty too long, they can affect the blower wheel by causing dirt to build up on it. This of course will limit its ability to function.

What to do when your furnace burner goes out?

Clean and lubricate blower fan and motor as per manufacturer’s instructions. Inspect the blower fan belt for wear and correct tension. Adjust as necessary. If the burner on your unit continuously goes out when the blower comes on, most likely some general maintenance and cleaning are needed for the unit.

What does it mean when your furnace is not heating?

If the flame sensor is defective, it might fail to detect a flame. If the flame sensor does not detect a flame, the co…ntrol board will shut off voltage to the gas valve to prevent the furnace from heating. Sometimes, if the flame sensor is dirty, it will fail to detect a flame.

What causes a Rheem furnace to shut off after a few minutes?

If the draft inducer motor is defective, it may be unable to close the pressure switch, causing the ignition process to stall and the furnace to shut off after a few minutes. If the ignition process stalls, the furnace will shut off. If the draft inducer motor is at fault, replace it.

What causes a carrier furnace to shut off?

If the control board is defective, it might not send voltage to the ignition system, causing the furnace to shut off after a few minutes. The draft inducer motor draws air into the heat exchanger and then exhausts it out the flue.