Why is My Home Heat Blowing Cold Air Only?

Why is My Home Heat Blowing Cold Air Only?

Cold Woman - Heat Blowing Cold Air


I have central heat and air. I had to reset the breaker for the furnace today. The heater never comes on in auto mode. I have a digital thermostat. I have also reset the breakers on the furnace itself. The blower will come on with it in manual. Why is my home heat blowing cold air only?  Any help would be nice.


Several possible things could be the cause of your home heat blowing cold air only. If your fan motor is not coming on when the thermostat is on the call for heat with the fan setting on auto, this could be caused by several issues.

One: The thermostat could be faulty.

Two: You have a break in the low voltage heat wire (white) from the thermostat to the furnace.

Three: Heat/fan relay at the furnace could be faulty.

With your furnace tripping breakers scenarios one and two are both unlikely.  I would suspect that the heat/fan relay is not turning on the fan but is energizing the heat causing an overdraw of current, which in turn is causing the tripping of the breakers.

Yahoo Answers

For more expert advice about heating and air conditioning maintenance, check out our other blog posts or Connect with us on FacebookTwitterPinterest or Google+ for HVAC tips and updates.

Call 251-610-2848 to schedule a service appointment with one of our highly qualified HVAC professionals.  We provide quality service to customers in Fairhope, Daphne, Spanish Fort, Foley and surrounding areas in Alabama.

Furnace Maintenance Checklist

Furnace Maintenance Checklist

It's Time for Your Furnace Cleaning with Comfort Climate Service

The heating season has finally arrived in the south.  It’s time for a comprehensive furnace inspection and tune-up by a qualified HVAC professional.  A properly maintained furnace will operate more efficiently and have a longer life span, resulting in immediate as well as long-term money savings.  Below is the Furnace Cleaning Checklist of maintenance tasks your HVAC professional should perform.


Furnace Cleaning & Maintenance

  • Observe operation of unit, paying close attention to operation of fans.  Loud fan operation can indicate premature bearing failure.
  • Clean flame sensor & flame igniter to remove carbon build up.
  • Inspect & clear all hoses to remove any blockages.
  • Check fan blades for dirt & buildup causing excessive unit vibration & noise.  Clean if needed.
  • Inspect blower door to ensure there is a good seal, preventing surrounding non-temperature controlled air from being drawn inside unit.
  • Check safety operation of blower door safety switch.
  • Check duct connections at unit for air loss into surrounding environment.
  • Test operation of the unit’s negative pressure safety switch.
  • Check return filter to ensure adequate airflow through return duct.
  • Clean burner rail assemble to remove carbon buildup, which can cause flame distribution to the heat exchanger.
  • Check all electrical entry points into the unit to ensure wire connectors exist & are secure.
  • Check wires & connections.  Replace any wiring showing signs of heat damage or with cracked insulation.
  • Check evaporator coil for blockage, which could prevent adequate airflow.
  • Check blower capacitor to ensure proper speed of fan motor.
  • Inspect all pipe fitting connections along gas line supply to ensure no gas leaks exist.
  • Check heat exchanger for cracks & corrosion.
  • Check combustion safety switch for proper operation.
  • Check for proper sealing at all combustion vent connections.
  • Check all duct lines for areas of collapse or excessive turns, which cause airflow restrictions.

For more expert advice about furnace maintenance, or to schedule a preventive tune-up with one of our highly qualified HVAC professionals, please contact Comfort Climate Service or call 251-610-2848.  We provide quality and prompt service in Fairhope, Daphne, Spanish Fort, Foley and surrounding areas in Alabama.

We strive to help educate our customers about energy efficiency and home comfort topics with regards to Heating and Air Conditioning systems.