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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

Why Your Furnace Output Might Be Low

We still have a month or two of chilly weather ahead of us, which means that you still need your furnace to put some work in before it can rest. If your furnace is not putting out as much heat as it should be, you shouldn’t ignore it. Random loss of output is usually a sign of a serious problem with the furnace, and should always be a source of concern. There are a number of reasons why your furnace output might be dropping, and you should have at least a bit of familiarity with them.

Thermostat Issues

The thermostat is the core of any climate control system, and so a problem with it can certainly be reflected in the furnace. If the thermostat is the cause of a drop in output from your furnace, it will likely manifest in what is called short-cycling. This is a behavior where the furnace turns itself on and off. Since the system can’t complete a full cycle, it will not be able to provide as much heat as it normally does. When a thermostat causes this problem, it’s typically due to a short in the wiring between it and the furnace.

Clogged Burner Assembly

If you’re one of the millions of people who uses a gas furnace, you should know that your burner assembly does need to be cleaned every once in a while. Carbon particles, formed as byproducts of combusting natural gas, collect on the assembly jets over time. Eventually, the carbon buildup can become so severe that some of the jets fire later than they are supposed to. This often generates a loud booming sound when the system starts up. If the carbon buildup is still not cleaned off, it can cause the entire assembly to become clogged. With a clogged burner assembly, the system will not be able to ignite the gas flow to provide heat.

Clogged Air Filter

Hopefully, you already know that you need to replace your furnace air filter at least once every three months or so. If not, you should know that a clogged air filter might be the reason that your furnace is not putting out as much heat as it should be. All air that flows into the furnace must pass through the air filter first. That means that if the filter is clogged, the air flowing into the furnace will be severely cut down. This prevents the system from distributing the heat it generates, since it cannot actually circulate air throughout the house properly. This can also lead to short cycling, as discussed above. Try replacing your furnace air filter, and see if that solves the low output problem. If not, you should call for a professional to take a closer look at your system.

Sunset Air offers a full range of furnace repair services throughout Olympia, WA. If you need furnace services of any kind, contact us today to schedule an appointment with one of our experts. We’ll make sure that your furnace stays in good shape.

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