5 Reasons Why Your AC Unit Smells Musty
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5 Reasons Why Your AC Unit Smells Musty

Musty-smelling air coming out of your air conditioner is a sign that something’s not quite right. It’s also a sign that you may need to have an HVAC professional come out and take a look at your unit. Here’s five reasons that your AC unit smells musty:

5 Reasons Why Your Ac Unit Smells Musty

Too Much Moisture

If you have excess moisture building up inside the air ducts and vents, it could lead to mold or mildew in the ducts. There are a few reasons this could happen, including high humidity, and unnoticed drainage leaks. If the air smells musty when your unit kicks on, there’s a good chance mold or mildew are the culprit.

It’s important to remember that mold can cause health issues, specifically to the upper respiratory system. Because of this, calling an HVAC technician as soon as you can makes sense, as they’ll be able to diagnose the problem, and get your unit cleaned and back to running the way it should.

Frozen Coils

The way AC units provide cool air is by taking the warm indoor air, absorbing it and pulling the humidity from it, and cooling it, after which point it is cycled back into your home through return vents. Having the air freely move through the system is vitally important. Making sure the filter is clean can help ensure the air is moving the way it should.

A clogged filter can inhibit the free-flow of air, causing water to collect on the evaporator coils. In turn, these droplets can freeze, impeding the cooling of the air. For this reason, filters should be checked and changed every two months.

Drain Pan

Your air conditioner’s drain pan collects excess water while your unit cools the air. After time, however, the drain pan may not function as it once did, and mold can build up on it. This also might be the cause of the musty smell you’re getting from the unit. An HVAC technician can replace a bad drain pan.

Condensate Line is Blocked

Your AC unit’s condenser is located outside of your home. It includes a small PVC pipe called the condensate line, right next to the condenser. The condensate line gets rid of the water in the drain pan. Because of its size, however, the condensate line is prone to mold, mildew, and sludge buildup, leading to both clogs and a musty odor.

This can be prevented, however, with regular maintenance. To clean the condensate line once a month, turn the AC off at both the thermostat and the breaker. From there, remove the condensate line, and put vinegar into the opening. Let sit for half an hour, clean with water, and re-attach.

AC Unit is Wrong Size

Having an AC unit that is either too big or too small for your home can create problems. If the unit is too big, the air gets cycled through your home too quickly, meaning it doesn’t get properly dehumidified. This can create a build up of moisture in the system. Having the wrong size unit may also lead to the air conditioner turning off and on constantly, which can wear out the parts quickly.

When thinking about installing an AC unit, check with an HVAC professional to make sure the unit you’re putting in is the proper size.

Have an HVAC professional address your musty air conditioning unit

A musty unit can put a damper on what should be the cool and carefree days of summer. If you’re experiencing a musty odor coming from your air conditioner, call the Fredericksburg area experts at Robert B. Payne Schedule an appointment today at 540-373-5876.

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