Skip navigation


Rentmeister Total Home Service Blog

How a Clogged Air Filter can lead to Furnace Repair

Many of the problems that can afflict your furnace are obvious in nature. If your air handler stops working, for example, you’ll know because you won’t get any heat. One of the most dangerous problems for your furnace, however, also happens to be the most subtle. If you don’t know what signs to look for, you may not even notice it until it’s far too late.

Let’s take a look at how a clogged air filter can lead to furnace repair.

The Air Filter

The air filter itself is designed to shield the furnace from any dust and debris that might blow in from the ducts. It’s pretty good at this role, capturing any particles that are blown into it, while allowing air to pass through it unobstructed. The problem is that once the air filter collects these problems, it has no way to get rid of them. In order for the air filter to keep working properly, it has to be cleaned or replaced every few months. If this isn’t done, the air filter can become so clogged with debris that it starts to obstruct the flow of air into the furnace. That’s when the problems start.


When the air flow into the furnace is restricted, it causes the temperature inside the system to rise. Eventually, the furnace will overheat, activating the limit switch and causing an emergency shutdown. Though this will temporarily protect the system from damage, it won’t address the source of the problem. As long as the air filter remains clogged, the system will overheat again as soon as it starts up. This locks the furnace into an endless start/stop cycle, which puts it under far more stress than it was designed to handle. If not fixed quickly, the entire furnace might break down and need to be replaced.

Short-cycling is one of the most damaging issues to afflict furnaces, though it is often one of the easiest to fix. If you haven’t been changing your air filter every few months, we highly recommend that you start doing so now.

If you’d like to know more about air filters and short-cycling, call Rentmeister Total Home Service. We provide furnaces throughout Salt Lake City.

Comments are closed.