January 7, 2020

Nothing can be more frustrating than having a furnace that is not able to blow hot air in the cold winter season. In many cases, this may be something easy to fix by yourself.

Furnace Not Blowing Hot Air? 5 Potential Reasons Behind the Issue

1. Thermostat Issues

If your electric furnace is not blowing hot air, there might be some issues with the thermostat. Here are some of the common problems related to a faulty thermostat.

  • Low battery
  • Sometimes the issue might be very straight forward like a low battery in the thermostat. If your thermostat runs on a battery unit, you need to check regularly if the battery is dead. Such batteries tend to send faulty temperature reading. This problem is especially common in older units. Even a low battery can malfunction your thermostat. In such cases, replacing the older batteries can solve the issue.

  • The fan is “on” all the time
  • Keeping the fan setting to “on” is a common mistake that results in the furnace blowing cold air. Heaters are not set to pump hot air continuously. Once the optimum temperature set by you is reached, it will take a break until the temperature again falls below the set temperature. However, in case the fan is set to be “on”, it will start blowing cold air during the downtime. To avoid this, make sure you set the fan to “auto” so that it will blow hot air when needed.

  • The thermostat might not be installed properly
  • Your thermostat could be malfunctioning if you missed something while installing the thermostat yourself instead of calling an HVAC professional. You could have installed a new thermostat that is not compatible with the existing heating system. In such cases, it is best to get professional help to install it correctly as soon as possible.

    Also read: How to Use Your Heat Pump Right to Save Money

2. Issues with the furnace filter

A dirty, clogged filter can restrict the airflow to your furnace which limits its ability to evenly distribute warm air in your home. Cleaning the filter could solve the issue.

3. Problems with condensate lines

The condensate lines always need to be kept clean and open. The condensate lines are regularly draining water away. It causes the lines to accumulate dirt, and get clogged. The excess buildup of dirt could lead the system to start blowing cold air and eventually shut down. Get a regular inspection done by HVAC professionals to ensure that the condensate lines are completely free of dirt and grime.

Also read: What Causes Furnace to Turn On and Off Frequently?

4. Gas valve problems

A gas furnace needs to be cleaned regularly. Dirt and debris can cause the gas valve to shut down or malfunction. If you’ve an old gas furnace, the gas valve could have worn out, causing the furnace to blow cold air. Scheduling regular furnace maintenance can avoid such issues.

5. Burner issues

When the burners of your furnace are clogged, there won’t be enough fuel for your furnace to keep blowing out hot air. In such cases, if your fan is still running, it could cause the system to blow out cold air, instead.

Also read: Furnace Duct Cleaning: Know About Their Pros and Cons

Troubleshooting Furnaces Not Blowing Hot Air

Here are some furnace troubleshooting tips you can try if your heater isn’t blowing hot air.

  • Check batteries of your thermostat and replace the drained or faulty one.
  • Check the fan settings on your thermostat if they are set to “auto” instead of “on”.
  • Make sure someone else has not set your thermostat to a lower temperature.
  • Thoroughly clean all the components of your furnace, which are vulnerable to dust and grime. You might also call HVAC professionals for thorough cleaning of the system.
  • Make sure the gas valve is open and not clogged with dirt.
  • Check whether someone forgot to shut the blower motor panel after repairing or cleaning.
  • Also read: How to Save Money on a New HVAC System Purchase or Replacement

Furnace Not Blowing Hot Air? Call an HVAC Professional!

Even after performing the necessary troubleshooting, if your furnace is still not blowing hot air, the best solution is to call HVAC professionals. If you’re in Orange County or surrounding areas, schedule your service online with White Mechanical, Inc., or give us a call at (949) 328-3370 for all your HVAC needs. Our professional HVAC technicians can diagnose and get the issue resolved fast.

White Mechanical, Inc.

Founded in 2002, White Mechanical, Inc. in Laguna Hills, CA, is one of the most trusted and licensed (HVAC) service providers, proudly serving Orange County and the surrounding communities. Our management team has more than 28 years of experience in various aspects of HVAC technology. All our HVAC technicians are professionally skilled and certified to deliver outstanding residential HVAC services as well as commercial HVAC services to our clients. We offer professional HVAC services including installation, maintenance, air conditioning repair, and more at very reasonable prices.

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