Why is my furnace fan blowing constantly?
When your thermostat is set to AUTO, your furnace fan should blow only when your furnace is in the middle of a heating cycle. But if your fan runs constantly, regardless of whether your furnace is heating, that’s not normal. There’s a shorted thermostat wire. There’s a shorted wire at the fan limit switch.
What causes a furnace to blow?
Your furnace may be blowing cold air because the filter is too dirty. A dirty air filter blocks airflow over the furnace’s heat exchanger, causing it to overheat. When overheating, your furnace can trip a high limit switch, causing the furnace burners to shut off so that the heat exchanger does not crack.
Why does my furnace blower fan stop working?
The function of the blower fan is to blow air across the furnace’s heating coils and disperse that warmth through the air ducts. If the blower fan stops working, you have a more serious problem at hand.
What should I do if my Furnace Fan is still running?
If your furnace fan is set to AUTO and is still running, then move on to the next section. Second, troubleshoot for fan limit switch problems. Your fan limit switch is located directly under your furnace hood and controls when your furnace blower turns on and off.
Where is the reset button on my furnace?
The furnace blower motor reset button location depends in many aspect, like the brand and model of your furnace. If you have both central heating and central air in your home, you will probably find your reset button on the blower motor.
Why does my furnace shut down when I Turn on the heat?
Furnace shuts down – Because your furnace has to run longer to heat your home, the heat exchanger overheats, causing the furnace to automatically shut down. A dirty filter will also cause soot to build up in the heat exchanger, causing your furnace to run inefficiently and reduce it’s life span.
Is there a reset button on the furnace blower motor?
Most electric motors, including the furnace blower motor, have a reset switch that pops up when this happens. Often the problem corrects itself and it is only a matter of pressing the reset button to get the furnace going again.
Why is my furnace blower fan not turning off?
Limit Switch Issue | Furnace Blower Fan Wont Turn Off If the furnace overheats, then a limit switch will open. That will cause the burners or heat source to shut off and the fan to run until the limit switch closes again. In some cases, the limit switch will stick open, and this will cause the fan to run continuously.
How to reset a furnace using the furnace reset button?
If the furnace doesn’t have a power switch you can turn off, turn off the circuit breaker controlling the furnace, open the blower housing and locate the reset button on the side of the blower motor. Press it in until it clicks and then restore power to the furnace by turning the breaker back on.
If your furnace fan is set to AUTO and is still running, then move on to the next section. Second, troubleshoot for fan limit switch problems. Your fan limit switch is located directly under your furnace hood and controls when your furnace blower turns on and off.
