It is cold outside and you return home with the expectation of comfortable warmth, and the last thing you need is to discover that your furnace is not blowing hot air. With that said, here are some common reasons for that occurrence. Some of the cases can be fixed by yourself with a little bit of patience. But there are some instances where you need to go for a furnace repair through a professional.
Furnace Fan Is Always Running
Take a look at the thermostat. If the fan is programmed to be “ON,” the fan will constantly operate, even when there’s no warm air. The cold air you feel is the breeze that is generated by the fan. Switch the fan to “Auto” from “ON” and the fan will only come on when there is hot air to circulate.
The furnace may be producing hot air, but a clogged air filter may be blocking the air from circulating properly. To fix this issue, all you have to do is to change the dirty filter. As long as the air filter is dirty, the furnace doesn’t get sufficient air supply. A clogged air filter also may result in your furnace to running more frequently – shortening its lifespan. Make cleaning or changing the air filters a regular part of your house maintenance routine.
For gas furnaces, check the pilot light. If it is out, check your owner’s manual for instructions on how to relight it. If unable to ignite the pilot, contact an HVAC service company.
A gas burner doesn’t light if the flame sensor is not clean. A dirty flame sensor will continuously switch on and off your furnace. Check your owner’s manual for instructions on clearing the flame sensor.
Insufficient Gas Supply
If there is not a sufficient gas supply, the furnace will not generate heat. Warm air will not be produced as a result. More importantly, insufficient gas supply can even make the furnace lockdown (as a precaution). Have the gas company check the gas pressure.
Drain Line Issues
Furnaces have drain lines to remove condensation. Clogged drain lines can hinder its performances. It is essential to clean the lines to bring back their peak performance.
Damaged Air Ducts
Damaged ducts are another common reason behind a malfunctioning furnace. Holes in the air ducts can allow cold air to be circulated. Depending on where the air ducts are located, the inspection can be by the homeowner or an HVAC service.
Wrong Size Furnace
The selection of a wrong-sized furnace can poorly heat your house. This situation can often happen when adding an addition to the home without upgrading the furnace. A furnace that is too small will never keep a home warm. The only solution is to upgrade to the properly-sized furnace.