3 Things That Can Go Wrong When Your HVAC Isn't Kept Clean

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3 Things That Can Go Wrong When Your HVAC Isn't Kept Clean

12 May 2023
 Categories: , Blog


You know your HVAC equipment needs to be serviced regularly so it won't break down, but you may not know what's included in a service call. One thing the HVAC technician does is clean the parts that have collected dust and grime.

A dirty air conditioner or furnace can malfunction or shut down. This is a problem that can be avoided by keeping the equipment clean. Here's a look at what could happen if you don't have your HVAC unit cleaned by a professional yearly or so. 

1. The Evaporator Coil Might Freeze

The evaporator coil is in the air handler on the far side of the blower. Air is pulled in through the filter, goes through the blower, and then over the evaporator coil to be cooled. If the filter or blower is dirty, dust will start to accumulate on the evaporator coil.

Since the coil is always wet due to condensation, the dust turns to grime that coats the coil. When that happens, the refrigerant in the coil can't cool like it should and the coil starts to ice over. Ice keeps building until your AC shuts down and leaves you sweltering in the heat. The coil then has to be cleaned off so your AC can start cooling again. If the filter and blower are kept clean, this problem can be avoided.

2. The Condenser Overheats

The condenser outside can have the same problem, but since it sits out in the rain, the insides get rinsed off occasionally. Still, if anything blocks airflow, the condenser can overheat since the lack of airflow keeps the unit from cooling down.

A cause for this is dirty fins on the side of the condenser. The fins are on the outside of the condenser coil which has to be cooled down. If air can't flow through the fins, the coils stay too hot and then the refrigerant can't cool your house very well.

The heat can even cause parts in the condenser, such as the capacitor or compressor, to go bad. The fins need to be kept clear at all times. You can even do this yourself as the summer goes on. Grass clippings, dirt, and leaves get stuck on the outside of the fins or between them. These can be rinsed away with a hose so air circulates freely.

3. The Furnace Malfunctions

An HVAC technician needs to clean your furnace regularly too, especially when you have a gas furnace that collects soot and dust. The burners can get coated with carbon and not function efficiently. If the flame sensor gets dirty, your furnace may not start because the sensor can't detect a flame.

If soot builds up in the furnace, it might blow out of the furnace in certain situations. If a burner doesn't ignite properly, a puff back can occur. These are small explosions that puff soot out of the furnace. These can be dangerous and strong enough to cause damage to the equipment. Fortunately, puff backs and ignition problems can usually be avoided by having an HVAC technician keep the furnace clean. 

For more information about HVAC services, contact a local company.