Why Is My Furnace Blowing Cold Air?

Winter nights in San Diego can get pretty chilly and the last thing you want to experience is cold blasts of air coming from your heating vents.  There are many reasons why this could be happening--some of them can be surprisingly simple and others require the help of an HVAC professional. 

Here are a few of the most common reasons why your furnace may be blowing cold air:

-It takes a few minutes for the warm air to reach the vents.  This is similar to the way it takes a couple minutes for hot water to come through your water faucet.  This wait time is completely normal and in no way means that your furnace isn’t working properly.

-The fan setting is not set on “auto.”  It the fan setting is set to “on,” that means air is being blown through your vents whether your furnace is on or not.  By switching it to “auto,” air will only blow when you need heat.

-The pilot light has gone out. If you have an older furnace then it's possible that the pilot light has gone out.  To fix this, following the manufacturers directions on how to re-light the pilot light.  If the pilot light is persistent on blowing out, we recommend contacting an HVAC professional because your furnace may need maintenance.

-The flame sensor needs to be cleaned.  If your furnace is blowing warm air but then it quickly goes cold, this could be because your flame sensor needs to be cleaned.  The gas burner will not stay lit when the flame sensor is dirty.  If this is the issue, then you will need to contact an HVAC professional and schedule a service call.

-There is a more complex technical problem.  If your furnace is blowing out cold air and none of the previous reasons seems to be the answer, you may have a more technical problem which will require the help of an HVAC professional.

Whatever problems you're experiencing with your furnace, call us at A+ Heating, Cooling, and Electric.  We can help fix all of your furnace issues and answer any questions you may have!