The Most Common Heating Problems and How to Fix Them

While winters in Montgomery, Alabama tend to be quite mild, we still experience chilly lows that make a heating system necessary in each home. We may not use our furnaces as often as those who live up north, but even so, it is possible to run into heating system malfunctions. If you’re wondering why your heating system isn’t working as it should, Hans Heating and Air discusses the most common heating problems and how to fix them in our latest blog post below.

1. Heater Won’t Turn On

If you ask yourself “why is my heating system not working?” and your heating system won’t turn on, there are a few potential causes. Often it is due to a lack of power or an issue with the thermostat settings. In older furnaces, the pilot light may be out, which will prevent the furnace from turning on and blowing hot air.

  • First, check to see if the power is turned on at the circuit breaker. Make sure the breaker to the heating equipment as well as your hardwired thermostat is on.
  • Another possibility is that the furnace itself may be turned off. Check the ON/OFF switch to the unit, which is typically located on the exterior of the furnace or positioned nearby on a wall.
  • If the unit has power, then the next step is to check the thermostat to see if it is set to “heat.”
  • Check the pilot light to see if it is lit. If it is not, then you’ll need to relight it. If the pilot light won’t stay lit, then there may be a problem with the gas supply.

If none of these solutions work, you’ll need to call a professional for help to get your furnace back up and running again. It’s possible that a broken or damaged component, such as a limit switch, is preventing the furnace from turning on for safety reasons.

2. Heater Won’t Turn Off

One of the most common problems with a heating system is a furnace or heat pump that won’t turn off when you expect it to. If it appears that your heating system runs around the clock, this issue is often caused by a simple incorrect thermostat setting.

Generally, the system’s fan should be set to AUTO, allowing it to run only when the furnace or heat pump cycles. If the fan is mistakenly set to ON, it will run all the time, with heating and without it. The noise of the blower fan and cooler air coming out of the vents often leads homeowners to believe it’s the gas furnace or heat pump running and that there is a problem because no heat is coming from the vents.

If you have a heating system that seems to run all the time, first check your thermostat to see the current fan settings. If the fan is set to ON, switch it to AUTO. This should stop the fan from running absent a heating cycle.

When you check the fan settings on the thermostat, if the fan is correctly set to AUTO, a thermostat wiring issue may be keeping the fan running constantly. Remove the faceplate of the thermostat, and check that all wiring is properly connected to the appropriate terminals. Make sure these connections are snug and use a screwdriver to tighten connections as needed. Replace the faceplate, reset the thermostat, and see if the fan turns off.

If your system fan continues to run, the thermostat may be due for replacement or a blower issue could be at play. These are issues for your HVAC technician to handle, so call for repairs.

3. Cool Air from Vents

Many of the most common heating problems involve lukewarm to cool air coming from vents or a lack of heating. There can be many causes for these most common heating problems, which we rundown below:

  • Check the thermostat’s fan settings as outlined above, as a constantly running fan could be blowing cold air through your vents.
  • On the thermostat, make sure HEAT mode is selected, not COOL. You could be running your home’s cooling system, rather than the heating system, by accident.
  • A dirty air filter can restrict air movement through the system, limiting the heat that comes out of your vents. Check the air filter, and replace it if it is dirty. Be sure to change out your air filters on a regular basis throughout the year.
  • If you have an older furnace with a pilot light, check to see that the pilot is lit. If it goes out, the furnace will not ignite fuel and no heated air will be produced, though the blower may continue to run and push air out of your vents. Relight the pilot if needed following the manufacturer’s directions – if it does not stay lit, call for furnace repairs.
  • Make sure your heating system has access to fuel. Check the gas valve on lines leading into the unit and make sure they are not closed. If you use an oil or propane furnace, make sure your tank has enough fuel – it may be time to schedule a refill.
  • Duct leaks may be causing heat loss as warm air travels to your living areas. Call your HVAC technician to assess your air ducts and perform duct sealing if needed, as ducts are often in inaccessible locations of the home and difficult to inspect by yourself.

4. Low Airflow from Vents

Low airflow from heating vents is often caused by a buildup of dust and debris in the vents. Over time, these materials can block the vents and prevent air from flowing freely. In order to troubleshoot this problem, start by checking the vents for any visible blockages. If there are none, then check the furnace filter. A dirty filter can restrict airflow and reduce heat output.

If the problem persists, it may be necessary to call a professional to service the furnace. Disconnected air ducts or air leaks in the ducts could be the cause of the low airflow problem, which requires repairs or duct sealing services to fix. Low airflow could also be caused by a problem with the blower motor.

5. Furnace Burning Odors

If you smell something burning when you turn on your furnace, it’s important to take action right away. The most likely culprit is a dirty or clogged air filter. As heating systems run, the air is pulled through the filter and into the unit. If the filter hasn’t been changed in a while, it can become clogged with dust, debris, pet dander, and other pollutants. All of these can build up, leading to restricted airflow and causing the furnace to overheat, leading to a burning smell. To fix this problem, simply replace the dirty filter with a new one.

Another possible cause of a burning smell is a buildup of dirt and dust on the furnace coils. These coils should be cleaned on a yearly basis to prevent buildup. If they’re not cleaned, they can cause the furnace to overheat and produce a burning smell. This is typically apparent on the first day that you turn on your furnace, but the smell should go away within a few hours.

If the furnace’s burning odor continues with a fresh filter and a good cleaning of the coils, it’s time to call for furnace repairs. Wiring problems in the unit can also cause a similar burning odor if the insulation has melted off the wires or has been damaged.

Fix the Most Common Heating Problems with Hans

If you need help figuring out why your heating system is not working, Hans Heating and Air fixes the most common heating problems that are unable to be resolved with some simple troubleshooting. If you experience any of the most common heating problems mentioned above and you can’t fix them yourself, contact us today to schedule a heating repair service.

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