On a cold winter’s day, there is nothing better than coming home to a warm and inviting house.

When your nose is red and your fingers are frozen, the last thing you want to discover is that your heater is blasting cold air.

Before you panic and check into a hotel or set your furniture on fire for warmth, there are a few simple things you can check that might solve the problem.

Here are some of the most common reasons why your heater is blowing cold air:

1. Check Your Thermostat

If you’re having heater issues, sometimes the solution to your problem is a simple one. Someone in your home or office may have been too hot and changed the thermostat settings.

If your thermostat fan is set to ON, the fan will blow cool air regardless of the temperature you have set the unit to. Ensure that your fan is set to AUTO.

If your thermostat runs on batteries, test them to make sure they are not weak or dead.

2. Light Your Pilot Light

If your furnace blows cold air the problem may be with your furnace ignition system. To confirm if this is the case, check your pilot light.

If the pilot light is out, then your heater is not lighting the fuel and therefore cannot generate heat. Follow the instructions in your furnace’s user manual to light the pilot light.

Wait a few minutes to see if the pilot light goes out again. If it does, check your gas supply. Make sure that your gas valve is switched on.

You should also clean your pilot light. If it is dirty, grit and grime may be obstructing the gas flow.

If none of these solutions work, and your pilot light keeps going out, you may have a faulty thermocouple. Your thermocouple sensor controls the gas valve and ignition. This a more serious fault, and you will need to call a professional technician, like those at BWS Plumbing, Heating & Air Conditioning, to adjust or replace the thermocouple.

3. Faulty Flame Sensor

If your heating unit cannot maintain a steady flow of warm air, your flame sensor may be to blame.

While your thermocouple detects if your pilot light is lit, the flame sensor monitors the furnace burners.

If your flame sensor is worn out or dirty, it may not recognize if your burners have turned off, and can even prevent them from lighting.

This is not a problem that you will be able to fix yourself. If you live in the Twin Cities metropolitan area, call in a team of experts from BWS Plumbing, Heating & Air Conditioning to either clean or replace the flame sensor.

4. Dirty Air Filter

A dirty air filter stops your heating unit from running efficiently. The dirty filter restricts airflow, making the unit work harder to pump out warm air.

To prevent the unit from overheating, a limit switch will shut off the burners, while your fans try to cool the furnace. This will cause your heater to blow cool air.

You should aim to change your air filters every 3 – 6 months. This will prevent restricted airflow and overheating. Frequent overheating will damage your heat exchanger, and a broken furnace is an expensive problem to fix!

5. Call in the Professionals

If none of the suggestions above get your heater back up and running, call in the BWS Plumbing, Heating & Air Conditioning professionals. BWS Plumbing, Heating & Air Conditioning will send in a team of expertly trained technicians to assess your heater problems and will have your home toasty and warm in no time!

BWS Plumbing, Heating & Air Conditioning is a one-stop-shop, assisting Minneapolis and St. Paul residents with heating repairs, replacements, and maintenance.

Now You Know What to Do if Your Heater Is Blowing Cold Air

As you can see, there are a variety of reasons why your heater is blowing cold air. Luckily, there are also a few quick fixes that can get it up and running again.

The good news is, you do not have to face this problem alone. Contact the team at BWS Plumbing, Heating & Air Conditioning for all your plumbing, heating, and air conditioning needs!

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