Summers in Charlotte, NC can be unbearable! The heat and humidity make us wish
for the cool days of fall. Extreme temperatures are not only tough on people, they
are especially hard on our home’s ac system. You may be faced with the question
above: Why is my air conditioner freezing up? It happens to be a very common
problem with air conditioners in the summer time. Let’s take a look at the causes and
what Patterson Heating & Air Conditioning can do about it.

Frozen Evaporator Coil

Here is an example of a frozen evaporator or indoor coil. This is located inside your
house attached to your furnace or inside your air handler if you own a heat pump. So,
what causes the ice to form? Let’s do a quick Q&A:

 Your system may be low on refrigerant (Freon). This could be caused by the ac system being undercharged from installation, or more commonly caused by a refrigerant leak in the system. Your home’s cooling system should never leak, it’s a sealed system.
 There may be insufficient air-flow, meaning your ac system is not moving enough air across the indoor evaporator coil. The main culprit in this case is usually dirty filters, so make sure you check them monthly and change them when they appear dirty. A good recommendation would be to change them monthly in the summer. There could be potential ductwork issues as well, kinked or broken ductwork will cause air-flow problems and poor home comfort.
 Mechanical problems with the system. If the motor that circulates air in the home is not running or not working at peak efficiency, it can cause the coil to freeze up. Also, restrictions in the refrigeration circuit will cause the issue, such as a kinked refrigerant line, clogged metering device (a piston), stuck txv, or clogged filter drier. If this is the case, you will need to contact a licensed HVAC contractor to assist.
 Running the AC when the outside temperature is lower. Air conditioners are not designed to run below certain outdoor temperatures, typically below 65 degrees. You will cause pressure problems in the system which will lead to your ac freezing up.

What can I do as a homeowner?

Preventative maintenance is the number one thing you can do as a homeowner to avoid
problems with your air conditioning unit. What do I mean by preventative maintenance?
We suggest you have your system maintained twice each year. Once for the cooling or ac
season, and once for the heating season. This should be performed by a licensed,
professional contractor. But, there are simple things you can do yourself.

· Change your air filters regularly and check them often
· Inspect both the indoor as well as the outdoor parts of your ac system on a consistent basis
· Don’t cover your supply or return vents with furniture or other obstructions
· Make sure the outdoor unit is not obstructed by landscaping or other debris

If you have any questions about more things you can do for your home or need repairs on your frozen air conditioning coils, call us at Patterson Heating & Air! We will diagnose your problem and apply over 70 years of experience to promptly repair your system.

(704) 288-4535