8 Reasons for Heating System Blowing Cold Air

Nothing worse than coming home expecting to find a toasty place where you can relax only to find out that your heating system is only blowing cold air, right? This is actually a pretty common issue. It could even happen with a furnace you’ve just recently bought. Don’t worry, though, there’s no reason to despair. Check out these common reasons why your heating system is blowing cold air and then call for a furnace repair to confirm your suspicions.

1. The Fan Is Off

Before anything, check to see if you have a thermostat problem. If you haven’t run the fan in a very long time, you may not have noticed it is turned off. Furthermore, if your thermostat is set on the “on” position, the furnace will continually run, which means cool air will be running through the system. Try switching it to the “auto” setting, and you should have heat again.

2. Dirty Flame Sensor

If you have a pilotless ignition furnace, the reason why your heating system is blowing cold air may be a dirty flame sensor. When the flame sensor gets covered in carbon and residue, it will turn off. Cleaning the flame sensor is not something you should attempt on your own. Leave this to a trained technician and don’t forget to keep up with your furnace maintenance next time.

3. Dirty Air Filter

So, it’s not the dirty flame sensor? Well, air filters get clogged with dirt, dust, and other debris, too. And when your air filter gets dirty, air can’t flow properly. It is recommended to change your air filter once every 30 to 60 days to keep your heating system running optimally.

4. Blocked Air Flow

The airflow in your home can get blocked, too. Over time, allergens and other particles can restrict the passage of air in the ducts and ventilation system of your home. You may also want to check that no items are blocking the registers of your furnace.

5. Tripped Breaker

If you have an electric furnace, a possible reason could be a tripped breaker. This prevents heat from circulating throughout your home. Your heating system may not even run at all. But if your furnace does manage to stay on, the air still can’t warm up.

6. Empty Oil Tank

Is your furnace oil-fired? Check to see if you’re out of fuel. If you are, the blower may keep circulating cold air despite the burners not lighting up.

7. Software Glitch

If you have a furnace with an electronic control panel, you could try resetting the system. It could simply be a software malfunction. If not, call a professional to see what’s wrong.

8. Heating Unit Is the Wrong Size

Not all furnaces fit in every home. Depending on the square footage, house design, and family size, you will want a certain type of furnace, one that’s capable of producing enough heat to keep your home comfortable. Check with an expert to see if you’ve made the right choice in picking out your current furnace.

Other possible reasons for heating system blowing cold air:

* The thermostat may have been adjusted by another member of the household.
* Your heater hasn’t had time to warm up.
* The gas supply is off.

If you’re not sure what is causing the issue with your HVAC system, it is probably time to contact a reliable heating technician. Trying to fix the issue yourself can be dangerous and you could also cause more damage to the unit.


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