Your central AC system isn’t working very well and you, being the handy and inquisitive type, go outside to see if you can spot a problem. Nothing there.

Next, you check to see if your thermostat battery has died. Nope, working just fine. Now where do you look? The next logical step is to check your air handler. Here in Southern Connecticut, it’s usually in the attic.

While you’re there, check for two things.  First, the filter. If it’s hopelessly clogged, there’s a very good chance you just solved the mystery. Cool air, you see, must work harder to break through built-up dirt and dust.

But what if the filter is as clean as can be…then what?  Easy: check the evaporator coil to see if it’s frozen. Or, if you see water around the base of the air handler, you’ll already know that some amount of freezing has already taken place.

How did that happen?  There are two probable causes.

Reduced Airflow

Before calling a professional, here are a few ways to check for reduced airflow:

  • Unblock return grills — Move curtains or furniture blocking return vents to help conditioned air flow freely.
  • Open closed supply vents in unused rooms — Contrary to popular belief, you don’t save money by closing vents; instead, it increases your electricity costs. Closing vents in unused vents also causes airflow problems.

Poor airflow also can be caused by a dirty blower motor, but it’s going to take Nero Air Conditioning & Heating to make that determination for you.

Low Refrigerant

When your AC system is low on refrigerant, pressure drops causing the evaporator coil to become abnormally cold. When returning air hits the coil, humidity/moisture from the air beads ups on the coil and quickly freezes. This continues until the evaporator coil is frozen.

While we’re out checking on the blower motor, we can also determine if a refrigerant leak has caused the drop in or complete loss of refrigerant.

Occasionally a leak can’t be repaired. In that case, one of the coils will need to be replaced. That’s a costly repair, and one that will make you think seriously about replacing your system, especially if it’s around 15 years or older.

One way to prevent problems with your AC system – including a frozen air handler – is with annual preventive maintenance performed by Nero, your local air conditioning and heating professionals. Annual service will help your system run better, last longer, and cost less to operate.  Contact us today to schedule service and rest easier knowing Nero has your back.

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