Managing Your HVAC System

Why Does Your Furnace Cycle On And Off?

If your furnace turns on and off too often, then it might have a problem. Irregular or too frequent cycling can be a sign that the furnace can't currently do its job. You might need to do some basic maintenance work or call out a furnace repair specialist.

Before you decide what to do, read on to learn more about why your furnace's cycle might have changed.

Inadequate Airflow

Furnaces need airflow to operate safely. If you lose airflow in part of your system, then your furnace might turn itself on and off repeatedly. Its sensors might not be able to gauge when to turn on and stay on. Or, too much heat might build up in your system and make your furnace's controls malfunction.

Sometimes, this problem has a simple fix. For example, if you haven't changed your filters recently, then take a look at them. If they are dirty and clogged up, then changing them should get things working again. Or, if you have something in front of your vents, then clear the space.

In some cases, you might need help from a contractor. For example, dirty, blocked, or broken blower wheels or motors can make a furnace cycle on and off repeatedly. You might need to have parts cleaned or replaced to fix the problem.

Faulty Flame Sensors

Furnaces have sensors to control the flow of gas into the system. These sensors keep things safe by detecting when the flame is on or off. When it is off, they shut off your gas supply to prevent hazardous leaks.

If this sensor develops a fault or simply gets clogged up with dirt, then it won't work correctly. It might not be able to detect the flame. When this happens, the sensor will shut off the gas and your furnace will cycle off. Your furnace will try to start again; however, the sensor will just keep shutting it down.

Sometimes, you can fix a malfunctioning flame sensor by cleaning it. However, if the sensor is corroded or damaged, then you'll likely need a new one.

Problematic Thermostats

Your thermostat controls when your furnace turns on and off. So, a change of cycling doesn't always mean that your furnace has a problem. Sometimes, your thermostat is at fault.

If your thermostat can't read the ambient temperature, then it doesn't control your furnace correctly. Sometimes, you simply need to change the batteries on your device to get it working again. If this doesn't work, then you need to have the thermostat's wiring and parts checked.

For more advice, contact a residential furnace repair service such as Paris Heating and Cooling.