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Why Is My Heater Blowing Cold Air?

uneven heat

When it is cold outside, the last thing you want is to be bombarded by cold air in your home. Sometimes, heaters stop functioning properly and deliver cold air instead of warm. This can be caused by a few different things, and Cates Heating and Cooling in Lenexa, Kansas, wants you to be aware of the things that could be keeping your furnace from producing hot air.

Common Reasons for Heaters Blowing Cold Air

While it is very frustrating when your heater isn’t keeping you warm, there are quite a few reasons that your furnace could be blowing cold air. Here are a few of the most common:

Thermostat Problems: For almost any HVAC issue, you should start by checking the thermostat. The first step will be to make sure the temperature is set to higher than the temperature in your home. Turn the temperature higher than the temperature in your home. If the air starts to feel warmer, then you have solved the problem.

Batteries can also be the culprit. Not all thermostats require batteries, but if yours does, when the batteries go out, your heater may not function the way you think it should. If you are unsure of the status of your batteries, put new ones in and see how the thermostat responds.

If it isn’t the temperature setting or the batteries, try the fan switch. There are generally three settings on the thermostat for the fan: “on,” “off,” and “auto.” If the fan is set to “on,” the furnace fan may run constantly no matter what the temperature is set on. You might try switching the fan to “auto” to see if that corrects the problem.

If all of those things still haven’t corrected the problem, it is time to check the temperature around the thermostat. The thermostat tends to read the temperature of the air around it, so if the thermostat is in an area that is warmer than the rest of the house or is in direct sunlight, then it could be reading that the whole house is warmer than it is.

Finally, you could just have a faulty thermostat that needs to be replaced or recalibrated. Fortunately, a new thermostat is an easy fix that won’t cost a ton of money. However, keep in mind that all thermostats should be installed by a professional to ensure that your equipment’s needs are all met.

Air Filter Problems: A dirty air filter can cause all kinds of problems for your HVAC system. If your heater is blowing out cold air, your second check should be the air filter. You will likely need to change out the dirty air filter for a clean one. In some cases, this will completely resolve your cold air issue.

Electrical Panel Problems: Electrical problems can be the culprit for improper air temperatures. The first thing you should look for is a tripped circuit breaker, which would prevent your furnace from working at all. A tripped breaker can also prevent the pilot light from turning on. Both of these could make your home feel colder than you would like it to be. Resetting the breaker should resolve your issue.

Tripping a breaker is easier than you have probably anticipated. Here are a few things that could trip your breaker:

  • Faulty wiring shoring the circuit
  • Overloading the circuit with too many things
  • Grounding faults and damaged wires

An occasional tripped breaker caused by running too many devices at the same time is normal, but if your furnace is causing your breaker to trip frequently, it would be in your best interest to not reset it and call a professional out to look at your system.

Overheating in your HVAC unit can also trip a breaker. An overheating furnace is usually caused by maintenance issues like dirty air filters and coils. You can prevent these issues from occurring by changing your air filter every month and getting annual maintenance checks on your HVAC system from a professional.

Ductwork Problems: Ductwork issues aren’t easy to spot, but cold air coming out of your furnace could be a clue that there is a problem. A leaky or broken air duct could be causing your home to feel cool even if you have the heat running. If your ducts are losing a large amount of warm air, it may be spilling into your attic, walls, or basement, instead of the rooms in your home.

Schedule regular maintenance checks with an HVAC company like Cates Heating and Cooling to catch ductwork damage early. Ducts will wear over time, so it is important that you have your ducts checked frequently for wear and tear.

If your ductwork is really old, you may need to start thinking about replacing it. Aging ducts are more likely to sustain damage, and they could be made out of materials that aren’t suitable for ductwork anymore.

Your home may also need better insulation to keep the air in your ducts warm. Adding insulation could quickly fix your cold air problems.

Furnace Size Problems: Have you noticed that your furnace doesn’t seem to keep up year-after-year? If so, the issue could be that the furnace just isn’t the right size for your home. Heaters that are too big or too small can cause problems. A furnace that is too small won’t be able to keep up with your heating needs. A furnace that is too large will heat your home too quickly, and the warm air won’t penetrate the insulation in the house. This results in the heater running too often and increasing your energy costs.

To find out of the size of your furnace is the problem, you will need to contact a professional. A Cates Heating and Cooling technician can help you determine the proper furnace size for your home.

If you are having problems with your furnace blowing out cold air, give Cates Heating and Cooling a call at 913-888-4470. Our technicians can come out to your home and provide you with all of the information that you need about keeping your furnace producing hot air throughout the winter months.

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