Furnace Problems: Furnace Blowing Cold Air

furnace problems

The cold weather has finally arrived in Ottawa and that means that furnaces are getting their first real workout of the season. It also means that we’re starting to get phone calls about all kinds of furnace problems Ottawa homeowners are facing. A common problem we hear about is the furnace blowing cold air—but there’s a twist.

This particular furnace problem has many homeowners stumped. They turn on their heating system and everything seems to be working—then, all of a sudden, their furnace starts blowing cold air. Their homes fill with cold air before the heat kicks on again. The cycle continues and there doesn’t seem to be any way to fix it.

We’ve encountered this problem many times and it’s usually one of two things:

Incorrect Thermostat Settings
The first thing you should check is the thermostat’s fan setting. The fan is what pushes air throughout your home and an incorrect setting could cause non heated air to be circulated.

Your furnace only turns on when the home falls below the desired temperature, so the fan should only turn on after the air has been heated—ensuring that only warm air is circulated. If your setting is set to “ON” the fan is always running, meaning that when the furnace shuts off, (cool) air is distributed to the rooms in your home.

Before calling for furnace repair, check that the thermostat fan is set to “AUTO.” Hopefully, this simple fix for a common furnace problem will get your furnace to stop blowing cold air.

Overheated Furnace
If your thermostat is set to the correct settings and your furnace is still switching between blowing warm and cold air, your furnace could be overheating. There is a safety switch on your furnace that will trip if the systems overheats, pushing cold air throughout your home. Often the cause of an overheated furnace is a dirty air filter.

If you suspect your furnace is overheating, save the furnace repair call and change your furnace air filter.

If neither of these suggestions works and you’re still struggling
with a furnace that is blowing cold air—
contact Team Harding today!

Harding Heating & Air Conditioning has been Ottawa’s leading home comfort specialists since 1994. We are a family owned and operated local business and all of our installers and technicians are fully licensed.

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