Constant overheating is a common source of short cycling. A damaged heat exchanger can also cause short cycling. Your heat exchanger transfers heat from one medium to another. In some cases, a cracked heat exchanger releases heat into other parts of your furnace, causing overheating and frequent on-off cycling.
The blower motor is what circulates the air throughout your house. It's possible your furnace will run when the blower motor is off; however, that's rare. But on the rare occurrence it does, there wouldn't be any air blowing over the heat exchangers which would cause your furnace to go off. The best way to check this is to hold your hand up near the vents to see if there is any air coming out. If there is no airflow or the airflow is weak, the blower motor is likely the problem.
The exhaust vent, is located on your roof and can also cause your furnace to short cycle. This happens when dirt, leaves, sticks, or other debris like a bird or animal nest ends up inside the pipe resulting in a blockage. This blockage will cause hot gases to build up in your furnace causing it to overheat.
If your furnace is too big for your home, it could cause it to short cycle. What happens when your furnace is too big for your home is it will heat your house too quickly then abruptly turn off. Then once your home starts to get cold again the cycle is repeated.
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