When the temperatures start to drop in Haltom City, TX, you simply adjust the thermostat accordingly and wait for your furnace to kick in and warm up your home. Sounds simple enough, right? However, the mechanism behind the furnace’s operation is anything but simple.

This is especially true with gas furnaces that have to heat up your home without exposing you to harmful gases. The pressure switch plays a role in this process. If it fails, your furnace will not work. What causes a furnace pressure switch to fail? The most skilled HVAC technicians in Haltom City, TX, cover the possible reasons in this post.

What Is the Heating System Pressure Switch and What Does It Do?

This component is a safety feature in gas-burning furnaces, which helps prevent the risk of carbon monoxide exposure. The switch also protects your furnace from catching fire and exploding. It achieves this by shutting down automatically as soon as it detects a problem that will cause negative pressure and make running the furnace dangerous.

All things being equal, the switch should work correctly every time, only shutting down your furnace when there’s reason to do so. Unfortunately, this isn’t always the case. This control setting can fail, wrongly shutting down the system.

The Top Reasons for Switch Failure in Haltom City, TX

So, what causes a furnace pressure switch to fail? Some of the main reasons for the pressure component failing include the following:

You Have a Faulty Inducer Motor 

The inducer fan system is responsible for creating the pressure that helps activate the heating unit’s pressure switch. If the system fails, then the switch won’t kick in. Thus, your furnace will not start a heating cycle. Unfortunately, the inducer fan system can pack up for various reasons.

Age-related wear and tear can affect the motor, making the inducer fan run too slowly to generate the right level of suction that the switch needs to run. In some cases, the motor may stop working completely. Either way, you’ll need to replace the inducer motor to get your furnace working normally again.

You Have a Blocked Vent Pipe

If you’re wondering why your furnace pressure switch may have failed, look no further than the vent pipe. The vent channels combustion gases away from your home safely. If there’s a blockage in it, the resulting airflow imbalance can trigger the switch.

Leave and debris are the main causes of blockages in vent pipes, but small critters may also nest in them. Clearing out the obstruction should allow the switch to work normally again.

Your Furnace Suffered Electrical Damage

A power surge can overload your furnace, leading to electrical failure that will burn out the pressure switch. It’s also possible for the electrical connection to the switch to become loose. In the latter scenario, fixing the connection should get the switch working normally again. For a burnout, however, you’ll need to replace the switch.

You Have a Pressure Tubing Leak

The switch has a small hose that helps it sense the air pressure difference. A loose or cracked hose will prevent it from working optimally. In this case, your furnace technician will recommend replacing the tube.

You Have a Clogged Condensate Drain

If you’re wondering what causes a furnace pressure switch to fail and you have a high-efficiency furnace, the problem might be your condensate drain.

The condensation that accumulates while these furnaces run must go somewhere. So, any clog in the condensate drain line can make it harder for the system to read internal pressure accurately. Thankfully, it’s easy to know when you have a clogged condensate drain.

Some of the top signs of a clogged condensate drain include water pooling around the furnace, musty or moldy odors near the system, and, of course, persistent restarts due to the switch not working as it should.