So you’ve turned on your furnace, it’s running fine but giving you the cold shoulder by blowing cold air.

What’s wrong?

Well, it could be due to multiple issues; some of them you can solve yourself and for some issues, you need to call an HVAC expert. Here are some of the reasons your furnace might be blowing cold air:

#1. Wrong thermostat setting

If your furnace is blowing cold air, there are chances that someone has adjusted fan settings from ‘Auto’ to “On’. In this setting, your fan will run continuously and will blow cold air. Change the setting back to AUTO, and you’ll have heat again.

#2. The Pilot Light is Out

If your old gas furnace is blowing cold air, it could be possible that the pilot light of your furnace must have gone out. You can re-light the pilot by following the manufacturer’s instructions mentioned in the manual. If you don’t know how to do it, contact an HVAC technician to lit the pilot light safely. If the pilot light doesn’t stay lit properly, the thermocouple of your furnace might be faulty. A thermocouple is a safety device that shuts off the gas if the pilot light goes out or the electric igniter fails. It may need to be adjusted or replaced, which is something an HVAC technician can take care of for you. Instant-Air’s HVAC technicians can help you fix the pilot issue within no-time.

#3. The Air Filter Is Clogged

Dirty air filters can limit the flow of air into your HVAC unit air handler. Restricted airflow means your furnace will run longer to heat your home until it overheats. The overheated furnace will blow cold air. You can fix this issue by cleaning the air filters or replacing your dirty air filters with a new one.  Once airflow gets proper, your furnace will be less likely to overheat and should function normally.

Furnace is Blowing Cold Air

#4. Problems at the source

Your blower may blow cold air if the burners fail to light and produce heat. You can face this issue if you don’t have enough fuel in the furnace, no matter which type of furnace you have in your home. Before switching on your HVAC unit, make sure to check:

  • Oil-powered furnace. Is there any oil in the tank?
  • Electric furnace. Is the furnace switched on at the breaker panel? Is the furnace itself turned on?
  • Gas-powered furnace. Is the gas supply valve open? If it’s not, theirs is no chance the fuel will ever reach the burners.
#5. Issues With Gas Valve

This is again a maintenance issue. There are chances that your furnace gas valves haven’t been cleaned in a long time. Dirt and debris might have collected in the valves, causing it to shut down. Another reason can be that the gas valve has simply worn out. To keep valves working, it’s really important to get your furnace repaired or maintained by HVAC professionals.

#6. Dirty Flame Sensor

The biggest problem with the flame sensor is they can get dirty, causing the furnace sensor not to function properly. If your furnace tries to turn on multiple times but ultimately does not run, you may have a problem with your furnace flame sensor. To keep a flame sensor clear, it’s necessary to keep your HVAC unit well-maintained.

Regular maintenance of your HVAC system is really important to keep your furnace run efficiently. Make sure that you hire HVAC professionals at least once a year to keep your HVAC unit run efficiently and smoothly.

Still facing issues with your furnace? This means something more serious may have gone awry. Your furnace must be blowing cold air due to the malfunctioning of a circuit board, a faulty igniter, damaged ductwork, or any number of more serious problems.

Get your HVAC system fixed by reaching out to Instant-Air professionals. We are a dedicated and highly motivated heating, air conditioning & electrical company with over 17 years of experience in the commercial & residential HVAC industry. Hire our technicians with the latest training and tools to avail prompt, accurate, and affordable heating services. You can call us at 856-401-7737 or book your appointment now!

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