4 Reasons Your Furnace is Turning On and Off

by Kevin Smith Author

The short cycling of your furnace occurs when it turns on and off frequently. Over time, this will cause your furnace to work much harder which will lessen its lifespan and could cause your utility bills to skyrocket. There are several reasons why your furnace may be rapidly turning on and off, many of which are easy fixes. Here are four of the most common reasons why your furnace may be short cycling and you may require a gas furnace repair in Pittsburgh, PA.

Dirty Air Filter

The most common reason why your furnace may be short cycling is that the air filter is dirty. A heating system works by the air being sucked into the heat exchanger where it gets heated and sent back out through ducts to the rooms of the building. Given the heat of the exchanger, air needs to get to it in order to avoid potential overheating. If the air filter is dirty, the air won’t be able to get through to the heat exchanger which will cause overheating and the system to shut down.

Misplaced Thermostat

The thermostat is an important part of a heating and cooling system as it determines the house’s ideal temperature and commands the system when to turn on and off. In order for the thermostat to record the right temperature and make the appropriate command, it should be in a part of the home that will be near the average temperature of the building. If it is close to a heat source, it will turn off the furnace thinking the building has reached the desired temperature and quickly turn it back on after realizing the mistake.

Corroded Flame Sensor

The gas valve is a part of the furnace that opens and closes to allow gas to reach the pilot light and burners, creating heat. The gas valve should be open when there is a flame but closed when there is no flame as gas could be released into the home. The purpose of the flame sensor is to determine when there is a flame to allow the gas valve to open or close. A dirty or corroded flame sensor won’t be able to tell if there is a flame and will close the gas valve, turning off the system.

Blocked Exhaust Vents

An exhaust vent, also called a flue pipe, is an important part of a heating system as it allows the gas to escape the home. If debris blocks the vent with objects like sticks or leaves, those hot gases have nowhere to go and will cause the furnace to overheat. Before any irreparable damage occurs due to overheating, the safety features of the system will turn it off.

The frequently turning on and off of your furnace can cause damage and the rising of your utility bills. These are four of the problems that might be the cause of this occurrence and the need for a gas furnace repair in Pittsburgh, PA.