It's January.  When you turn the furnace (aka heating system) on, you expect to only feel warm air coming through your vents.  You may be surprised to know that is not always the case.  One of the most common complaints I hear this time of year is, "why is my furnace blowing cold air?".  Of course, the answer is:  it depends.  However, here are the most common reasons:

• The thermostat is set to continuous fan mode. 
  • You know that little slider for the fan control that can be set to "on" or "auto"?  If you set it to on, the fan will consistently run.  It is a nice feature to filter/clean the air and keep the air flow moving. 
  • Regarding the cool air, if you use this setting and have the temperature set at a comfortable 68 degrees, the furnace will blow out air to target that temperature.  If rooms are already heated to 68 degrees, the furnace may blow out room temperature air to keep the temperature constant. 

• The thermostat is set to cool mode.
  • Adjusting the temperature higher may not be enough.  Sometimes, you have to ensure that your system is set to heat.  If your system is set to "cool", that may be the reason it is blowing cold air.

• The heating system is broken. 
  • In this case, it is best to call a professional.  If you are in the Atlanta metro area, we would be happy to help.  Call the HVAC professionals at Atlanta Energy Solutions, LLC: (404) 803-7471