Reasons Heaters Or Furnaces Produce Cold Or Lukewarm Air

November 4, 2022

Reasons Heaters Or Furnaces Produce Cold Or Lukewarm Air

Nothing beats coming home to a warm and welcoming apartment on a chilly winter day. The last thing you want to find out is that your heating system is blasting cold air while your nose is red and your fingers are numb.

During the winter, one of the most common calls HVAC contractors in Edmonton receive is regarding heaters blowing out cold or lukewarm air. But the good news is that you can often resolve this issue with a few simple debugging steps.

The following are a few of the most common reasons why heaters and furnaces blow cold air.

A Dirty Or Bad Air Filter

Air filters improve indoor air quality, and you should replace them every few months to ensure that your HVAC systems are able to run as effectively as possible. Air filters are critical HVAC parts used to maintain the cleanliness of your furnace and to help it continue to pump out warm air throughout the winter.

When troubleshooting lukewarm air flowing from your furnace, examine your air filters for the following typical issues:

  • Check to see if your filter is dirty
  • Make sure you have the proper air filter
  • Check to see if the filter is pointing in the right direction

Faulty Thermostat

If you’re having heating problems, sometimes the solution is as basic as it gets. Someone in your house or office may have been uncomfortable and altered the thermostat settings.

If your thermostat fan is turned on, it will blast cool air regardless of the temperature you have set the device at. Make sure your fan is set to AUTO. If your thermostat is powered by batteries, make sure they are not weak or dead.

Damaged Ductwork

Air leakage is one of the most frequent causes of lukewarm or cold air being released. If your ductwork is compromised, air will seep through before reaching your vents. Not only will you have to live in sweltering temperatures, but you’ll also have to pay a hefty price on your monthly energy bill to compensate for the lack of conditioned air.

When there are cracks in the ductwork, the air pressure drops dramatically. An HVAC professional will be able to determine whether this is the cause of your temperature decline immediately. Once discovered, the expert will patch the gaps because even the tiniest leaks will have an impact on the interior air quality and temperature.

Problems With The Core

If your thermostat is functioning properly but your heating system is still blowing cold air, the heater core might be the source of the problem. The heater core is made up of two components: tubing and fans.

The tubing transports the heated coolant, while the fans dissipate the heat produced by the coolant. The core is responsible for both heating and defrosting. The heater core can cause a variety of issues due to its numerous components, including obstructions in the tubing that prevent the coolant from flowing correctly through the heater core.

If you smell anything sweet coming from the vents, the coolant may not be reaching the fans.

Faulty Flame Sensor

If your heating unit is unable to maintain a constant flow of warm air, your flame sensor is possibly to blame. The flame sensor watches the furnace burners while your thermocouple determines if your pilot light is lit.

If your flame sensor is damaged or unclean, it could fail to detect when your burners have shut off and may even prevent them from igniting. You can’t handle this problem on your own. Contact an HVAC expert for furnace maintenance services.

Inadequate Gas Supply

There is also the potential that the system is under pressure due to a lack of gas. As a result, even if the system is on, the furnace will either not heat up at all or heat up very little. As a quick fix, check the gas supply to see whether it is still switched on. If you are unsure, contact your gas supplier.

You might watch your furnace when it turns on to check whether the burners ignite and heat up. If they do, the problem isn’t with the supply of gas. However, it might still be a problem with the thermocouple or indicate a problem with the flame sensor.

Also Read: Why Is My Air Conditioner Blowing Warm Air?

About Nor-Can Heating & Air

Nor-Can Heating & Air is an Edmonton-based HVAC installation, maintenance, and repair company. We also provide dependable repair and replacement services for all types of humidifiers. Learn more about Nor-Can Heating & Air. Have issues with your HVAC system? Contact us now.


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