If your furnace is running constantly, this could be a sign that your furnace is in need of maintenance or repair. During the winter months, it is typical to hear your heat click on and off a few times per hour. A normal furnace cycle time is 2-3 times an hour. If you have noticed it has been running constantly, or it is stopping and starting every couple of minutes, then you will want to have it checked out by a trusted HVAC Professional. 

A furnace that runs constantly could be caused by several factors.  


Check your Thermostat setting. Make sure your Thermostat is set to Heating or Auto. If your thermostat is set to fan, it will make your heater fan blow constantly.

When the heat is set to a higher temperature during the coldest part of the day, this sometimes causes it to run more often, and makes your heater run for a longer period of time.

If your heater is still running constantly even during warmer parts of the day, you should check your air filter.

Air Filter

When your filter isn’t changed regularly, it can clog and slow the air flow to and from your heating unit. This causes the heater to work harder to heat to the desired temperature, making it run for a longer time.

It’s time to change your filter when you see dust and debris on the filter. This means dust and debris is getting into your heating system, which shortens your system’s life and efficiency. Replace your air filter regularly and often with the cheapest filters. The thinner, less expensive filters allow the most air flow to your heating and cooling system. This is compared to more expensive filters that are thicker and restrict air flow. Depending on whether or not you have pets, filter replacement could be once every 2-4 weeks, or once every 3 months. The takeaway is that you change them before they are visibly dirty.

Call a Professional

If your furnace is still running constantly, do not risk any further damage to your heating system. Schedule an appointment with your trusted HVAC professional today to ensure a proper diagnosis and repair.