HVAC Construction, Inc.

You stand there scratching your head because you know it’s hot outside, yet you have a frost building up on the refrigerant lines and evaporator coil of your heat pump. That’s a sure sign that you definitely have a problem. That should not be happening. Fortunately, it’s not that hard to diagnose and fix heat pump freeze up.

If you let this go and take no action the refrigerant in your AC will freeze over clear back to your compressor and it will destroy it. Compressors are an expensive part to try to replace.

What to Do for Heat Pump Freeze Up

Turn off your system immediately before any further harm can come to it. Next you want to switch your fan setting on the thermostat from ‘auto’ over to ‘on’ and let it defrost your coil. Here is an explanation of why your heat pump may be freezing over –

The job of the evaporator coil is to absorb the heat from your air by using cold refrigerant. Condensation builds up on your evaporator coil whenever it makes contact with warm air, much like little droplets of water bead up on your glass when you have ice water when it’s hot outside. However, if your evaporator coil gets too cold, then it will freeze the condensation. Everything goes downhill after that. The frost will insulate the coil from all surrounding heat and cause it to ice over more.

Other Possibilities for Heat Pumps Freezing Over

Whenever your system gets low on refrigerant, it causes the pressure to drop even lower than usual which makes the coil unusually cold. It’s very similar to spraying with an aerosol can, the pressure within the can drops very quickly and gets cold, then it ices up. Whenever the evaporator coil becomes too cold because of low pressure, the condensation formed on the coil will freeze very quickly. Refrigerant never gets ‘used up’, which means the problem has to be a leak or improper refrigerant charge.

Poor Airflow – Whenever you don’t have an adequate amount of warm air blowing over your evaporator coil, it freezes. Keep an eye out for anything that could be reducing or restricting your airflow (filters, blocked vents, blow malfunction, etc.).

Dirty Coil – Evaporator coils are wet when they’re running which means dirt will stick to them easily. That dirt can insulate the coil and stop warm air from flowing over it, which in turn causes your coil to become too cold and it freezes over. It will take a professional to handle this problem.

What to Do Right Now for Heat Pump Freeze Up

(1). Change Your Air Filter.
(2). Defrost The Unit Using Your Blower (set your fan to the ‘on’ position).
(3). Open Up Closed Vents Anywhere They Exist in Your Home and Unblock Them.
(4). Turn the Unit On and Let it Run 30 Minutes to see if it Happens Again.

 

 

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