A heavy winter workload can cause failure in your home's heating system, particularly if it is older or has not received regular maintenance. A trained technician may be needed to resolve many issues with heating and cooling systems, but in the winter these specialists are in high demand. Before you call (and possibly, wait for) a technician, there are a few basic troubleshooting steps you can take to try to get your heating system back online. As always, you should consult your owner's manuals for further details and leave advanced repairs to the professionals.

1. Gas Furnace

  • Double-check the circuit breaker or fuses for the furnace system, resetting the breaker if it has been switched off.
  • Power down the furnace unit (the power switch is typically located next to or inside the furnace cabinet). Turn the power back to ON and wait several minutes for the furnace to engage.
  • The motor for the blower may need to be reset due to an overload. Look for a "reset" button close to the blower motor. Press "Reset". If there is no response, wait approximately 30 minutes to allow the motor to cool prior to trying the button again.

Look to see if the pilot light is on. If it is not, try the following:

  • Open the panel and turn the control knob to pilot.
  • With a flashlight, locate the pilot fixture and light it with a match.
  • Set the control to "on".
  • Set the thermostat to high to see if they system is operational.

It may be necessary to repeat this process several times. Turn the control off and start over.

2. Forced Air Heating System

  • Double-check the breaker for the heating system, resetting the breaker if it has been switched off.
  • Turn off power to the unit.
  • Check all ventilation areas to make sure they are not covered by furniture or blocked in any other way.
  • Check for noticeable air leaks in ducts around the unit. Seal any leaks with several wraps of duct tape.
  • Look for the door or panel that covers the blower. This may be marked "filter". Remove the door/panel.
  • Check the air filters and clean the grill. The filter should be marked with a size (if disposable) or cleaning instructions (if permanent). Most newer metal filters can be rinsed with warm water to clean, but check the manufacturer's recommendation or owner's manual to be sure.
  • If replacing a disposable filter, make sure to slide it in facing the proper direction.
  • While the furnace is still open, vacuum out the area around the blower.

3. Steam Heating System

  • Turn off power to the unit.
  • Check the water level in the boiler. If the level is low, slowly add water.
  • If the water level appears low shortly after re-filling, call a technician to check for potential leaks.