Easy Furnace Troubleshooting Tips You Can Do on Your Own

Posted: 2023-02-02

For the most part, your furnace works in the background, without you having to worry about it. But when it stops giving warm air, what do you do? What if you have to wait because no technician is available at the moment? Thankfully, you can perform basic troubleshooting steps to help you understand what’s going on.

Four Seasons Air Specialists has been a premier heating company in Circle Pines MN for over forty years. We are experts at diagnosing furnace problems and applying appropriate, long-term solutions. We want to share a few details you might find helpful.

Thermostat Settings

This one may seem like a no-brainer, but a lot of people call their HVAC contractors without even realizing that their thermostats are not properly set. That’s why the first thing you want to verify is that the thermostat is set to the “HEAT” position. Check your thermostat and see if you can physically program it to the right setting. This tiny switch can easily get moved, like during a housekeeping activity. If you have a smart thermostat, you should be able to check it on the display.

Also, find out if the thermostat is set to a temperature that will actually turn the unit on. Allow the furnace’s fan to work and the heat to start. If nothing seems to work, try setting the thermostat to 90 degrees Fahrenheit. This way, it won’t turn on and off unnecessarily while troubleshooting.

Blower Settings

If you notice that the furnace’s blower runs constantly, two possibilities come into play. First, the thermostat is set to the “FAN” setting, causing the blower to run uninterruptedly. Sometimes, keeping the fan running is desirable, such as when you want to clean the air or dehumidify your home. But in most cases, it wears down the blower prematurely. To avoid this problem, change the blower set to “AUTO” and allow the fan will run only when the system is heating.

Also, your furnace is equipped with a fan limit control switch that monitors the temperature inside the unit and turns off certain parts when the set temperature is reached. If the blower runs non-stop, it could be that the limit switch is malfunctioning. For the most part, resetting the fan limit control switch resolves this problem. If not, this part may need replacement. In such a case, you may need professional help to make sure the operation is spot-on and safe.

Filter Management

Your furnace comes with an air filter that cleans the air that goes into the furnace as well as the warm air that circulates throughout your home. It gathers dust, debris, and other particles in the air, keeping them from accumulating in the system.

This part requires regular cleaning to ensure it works efficiently. When you fail to clean or replace your filter regularly, it will gather too much debris that can compromise airflow, which is essential to the entire system's proper functioning. This lack of airflow adds pressure to the system, causing it to work harder than usual. When ignored, this simple issue can cause high operational costs, subpar heating, and premature part failure.

Unfortunately, a neglected filter is one of the most common yet unnecessary maintenance issues homeowners experience. If you have a relatively new furnace, you should be fine because new furnace models automatically shut down before too much dirt is collected, prompting you to clean or replace the filters. Unfortunately, older units don't have this function and will continue working, but with a significant drop in efficiency.

Ideally, your filter should be replaced every three months, depending on usage. But during extreme weather, when the furnace works continuously, it is recommended to replace your filter at least once per month.

Refer to your user's manual to determine whether you have a reusable or a replaceable filter.

Problem too Complicated? Call Four Seasons Air Specialists

If these steps don’t mend the issue, and you think that the problem is too complex, talk to one of our Shoreview furnace repair professionals. With decades of experience in the heating and cooling industry, we sure can determine the problem, apply the right solutions, and restore your heat in no time.