There are several things that could cause your gas furnace to blow cold air, and not all of these problems require assistance from a furnace repair professional. Knowing the causes of this problem (and the solutions) can help you avoid unnecessary repair calls. In addition, knowing how to troubleshoot this problem can help you avoid having a cold home in the middle of winter.
What might cause your gas furnace to blow cold air?
Some of the most common reasons that your furnace might blow cold air include:
- Extinguished pilot light
- Clogged air filter
- Leaky air ducts
How can you trouble shoot your furnace before calling for a repair person?
If the furnace is blowing cold air, check the pilot light. Different furnaces have different instructions for checking the pilot light. However, your furnace should have instructions for locating the pilot light posted on the outside of the unit. Follow the instructions to check the pilot light and ignite the pilot if the flame has gone out.
If your furnace is still blowing cold air, there are several things you can do to trouble shoot the problem before calling for a repair person. To begin with, you can try replacing the air filter in your system. If your HVAC system's air filter is dirty, your air filter could be stopping much of the warm air. To replace the air filter, turn off the HVAC system and pull the air filter out of its compartment between the return air duct and the blower. Take the air filter to a home improvement center and purchase a filter similar to the old filter. Then, put the new air filter back in the slot and turn on the HVAC system.
If the furnace continues to blow cold air after checking these two potential problems, this could be an indication of a leaky duct. To check the ducts, go into the attic of your home and inspect the ducts. If a duct is experiencing a leak, you'll see a tear or a hole between one duct and the next. Wrap the hole with duct insulation and tape it in place with duct tape.
What if none of these solutions seem to work?
After all that, if your furnace is still blowing cold air, it's likely that your furnace is experiencing a mechanical failure. If this is the case, contact a furnace repair person like Anytime Plumbing Services or others to fix your unit. He or she can check your system, diagnose the problem and make recommendations for repair.