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Serving Franklin and Washington Counties since 2012





Serving Franklin and Washington Counties since 2012


Premier HVAC Services Blog

When a Furnace Blows Cold Air: Troubleshooting Your Heater

It’s time to re-explore an issue that we get called about a lot during this time of the year—a furnace that’s blowing cold air. This is of course a very unsettling problem and not one that you want to face. When your furnace suddenly starts blowing out cold or lukewarm air from the vents, it’s easy to panic. But before you do, check out our advice below.

The thing is, there are a number of reasons that a furnace may experience this problem. Some of them amount to nothing more than “user error” while others are of course more serious and will require a professional to fix. Read on to determine which is the case for you.

Thermostat Trouble

Sometimes a problem with a furnace isn’t a problem with a furnace at all. What we mean, is that the problem might be coming from the thermostat. Yes, it could be malfunctioning and reading indoor temperatures incorrectly or not properly regulating the temperatures, but another possibility is that user error we mentioned above.

There’s no reason to be embarrassed (you don’t even have to admit to us that this is what happened) but what we’ve found in a few cases is that homeowners have their thermostat set to “on” instead of “auto,” and when they feel cold or lukewarm air, it’s because the fan is on, but the furnace isn’t generating heat because the indoor temperature is already what you have set on the thermostat.

Check to see if this is the case. If it’s not, read on!

A Dirty/Clogged Air Filter

When the furnace air filter gets too clogged up, it can start causing problems. What happens is that it restricts airflow into the furnace, which causes the system to overheat. When this occurs, the system will shut down as a safety measure. The fan, however, will keep blowing air to cool down the heat exchanger, so as a result you might feel cool air coming through the vents.

You can prevent this from happening by changing your air filter out every 1–3 months, depending on the type of filter. Please don’t hesitate to ask our professionals for guidance if you’re unsure how often you should be changing yours.

Broken Heating Elements

So let’s say the neither the thermostat or the air filter are to blame. If you have a gas-powered furnace, this doesn’t apply to you, as combustion gas heats up these types of systems. But an electric furnace can suffer from broken heating elements. Our professionals can closely inspect each element to pinpoint the exact source of the problem and repair it accordingly. You want any broken heating elements repaired right away to restore functionality.

Damaged Ductwork

When there’s a breach in your air ducts, warmed air can leak from the ventilation system. In addition, a breach will cause air from other parts of the home, most of it colder than the air from the furnace, to enter your furnace. This will cause a drop in temperature. Fortunately, our team is here to help.

For expert heating services in Chambersburg, PA and the surrounding communities, contact Premier HVAC Services today!

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