Air filters are such small parts of forced air heating systems, and such simple ones. It’s just a simple woven mesh stretched across a frame, and inserted in the air return duct. Despite how trivial it seems, however, the air filter is actually one of the most important parts of any forced air combustion heater. If it is not taken care of properly, it can create all sorts of issues for your heater. This is especially true if you’re a furnace owner, like the majority of Americans. Let’s take a look at what can happen when you don’t clean or replace your air filter every few months.
An air filter that isn’t cleaned or changed every few months will become clogged with the very particulates that it is supposed to protect the furnace from. This will cause it to restrict the flow of air into the furnace, which will cause the temperature inside the furnace to rise. This activates the limit switch, a tiny part that measures the temperature inside the furnace. The limit switch will shut down the furnace when it reaches dangerous heat levels, but it won’t be able to address the source of the overheating. When the furnace restarts, it will overheat and start the entire process over again. This traps the furnace in a constant startup/shutoff cycle, which is extremely bad for it.
Effects of Short-Cycling
The startup cycle is the most stressful part of a furnace’s operation. It is during the startup cycle that the furnace runs constantly until it manages to reach the temperature the thermostat requires. After that point, the demand levels off and the furnace only needs to make occasional adjustments to keep the temperature constant. By trapping it in the startup cycle, however, short-cycling puts the furnace under an immense amount of strain. This substantially increases the risk that the furnace will break down, as well as shortening its lifespan. If the furnace is left to short-cycle for too long, the entire thing may have to be replaced.
If you notice your furnace short-cycling, turn it off immediately and call Command A/C. We clean and replace air filters throughout the Huntington Beach area.