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Serving the South Puget Sound and Western Washington Areas Since 1976

Serving the South Puget Sound and Southwest Washington Areas Since 1976

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Sunset Air Blog

Furnace Short Cycling: What You Need to Know

The further we move into heating season, the more stress you’re going to be putting on your furnace. That may give rise to a number of problems, the most dangerous of which is known as “short cycling.” Let’s take a look at short cycling, what causes it, and how it can be prevented.

What Is Short Cycling?

Short cycling is a behavior in which the furnace turns itself on and off every couple of minutes. While this may just seem like an odd quirk, it is actually a very serious problem. Short cycling puts the furnace under far more stress than it is designed to handle normally. This increases wear and tear on the system, elevating the chances of a breakdown and shortening the furnace’s lifespan.

What Causes Short Cycling?

Short cycling is typically caused by a clogged air filter in the furnace, which traps heat in the main chamber. This causes the temperature in the main chamber, or “plenum,” to quickly rise above established safety parameters. As a result, the limit switch activates and shuts down the system to protect it from overheating. Unfortunately, this doesn’t actually solve the cause of the overheating. So when the furnace turns back on it will overheat again and be shut down once again—and the cycle will continue endlessly.

The best way to prevent short cycling is to have your furnace air filter cleaned or replaced every few months while you are using it. If you don’t know how to do it yourself, one of our professionals will gladly assist you. If your furnace is already short cycling, though, you need to call for repairs immediately in order to prevent as much damage as possible.

If your furnace need repairs, call Sunset Air. We serve all of Olympia, WA and the surrounding areas.

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