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5 Reasons Why Heaters Blow Out Cold or Lukewarm Air

Serving Families Throughout Dallas
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One of the most common calls we get during winter is about heaters blowing out cold or lukewarm air. The good news is that sometimes this problem is something our customers can easily fix on their own with just a couple of troubleshooting steps.

Below are five of the most common reasons why heaters blow out cold air, along with suggestions for what to do in each scenario.

1. The system is still getting warmed up.

When you first turn your heater on for the season, it can take a while before air coming out of your vents feels warm. The air your furnace heats has to travel through cold ductwork, where it can lose a lot of heat along the way. Once your ductwork has warmed up, not as much heat will be transferred to it as air blows through it. At that point, the air coming out of your vents should start to feel warm.

2. Your thermostat is set to the incorrect setting.

It always pays to double-check your thermostat settings. You want the device to be switched to “auto” so that it will only circulate air while your heater is heating the air. If your thermostat is set to “on,” then your system is going to circulate air throughout your home whether that air is getting warmed or not.

3. The air filter got too dirty.

When you leave an air filter in too long, it can get clogged with dust, and when that happens, it restricts airflow through your heating system. The less airflow your system has, the more likely it is to overheat. Some furnaces are equipped with a high limit switch, and when the system gets too hot, that switch will shut off the burners to prevent extensive damage. Trying replacing the filter and resetting your furnace (if necessary), and this will most likely solve the air temperature issue.

4. Your air is losing warmth through your ductwork.

If you live in an older home and the ductwork has never been replaced, there’s a huge probability that the air ducts have a lot of gaps, tears, and holes. This can happen due to normal wear and tear, aging materials, and pest activity. If your ductwork has seen better days, we recommend getting it replaced and sealed. You’ll notice a definite improvement in your system’s performance and your heating and cooling bills.

5. Your furnace is having an ignition problem.

When your furnace can’t burn fuel as efficiently as possible, it will struggle to heat your home while simultaneously producing more pollutants and increasing your heating costs. Furnace ignition issues frequently occur due to a lack of annual preventative maintenance, but there might also be a problem with the gas and oxygen mixture being supplied to your furnace’s burners. In either case, we recommend involving a professional HVAC technician to help you get to the root of the ignition issue.

Fast and Fair With Your Repair

If you need dependable and top-quality heater repair in Dallas, TX, please call Rescue Air and Plumbing at (972) 201-3253 or use our online form.