UncategorizedAugust 16, 2022by Alex

Why do the outdoor unit air conditioner’s pipes freeze?

When inspecting the outdoor unit, a layer of frost can sometimes be detected. At this point, there is no need to panic and rush to order an air conditioning repair, because the condition can be explained by natural causes.


For example, pipes could be frozen because of long idle time during the winter. After switching on the device they will thaw for several hours. Also, if there is no good external protection, frost can sometimes appear and then turn into condensation. If the tubes freeze under other conditions, however, it is best to carry out a diagnosis. The risk of faults is quite high.


In what cases is it practical to repair air conditioning units when the tubes are frozen?


There are two tubes in the outdoor unit – a thick tube and a thin tube. Let’s look at the causes of frostbite in each one. The thick tube gets covered with ice due to the following circumstances:


Contamination of one or more units. Comprehensive cleaning of the appliance is required.


Failure of the fan. Repair of broken parts or their complete replacement can help.


Improper operation of the expansion valve. Proper adjustment of the system is necessary.


The thin tube starts to freeze due to the following reasons:


Capillary tube blockage. Hydraulic cleaning or tube replacement can help.


Lack of refrigerant due to leakage. Complete sealing of the system is necessary.


Failure of expansion valve or expansion valve. Valve adjustment or repair if necessary.


In some cases, air conditioner repair is required due to the simultaneous freezing of both tubes. In these situations, a thorough diagnosis using specialized equipment is necessary to identify the problem.


Repair of air conditioners under other circumstances

Frosting of the external unit is also possible due to other causes. Among these, the most common are:


– malfunction of the control board;

– damage to the 4-way valve;

– Failure of the temperature sensor.


To pinpoint the cause and then repair it as quickly as possible, contact SDAC Heating & Air Conditioning. We’ll have your unit back up and running within the same day of the call, so you can continue to enjoy a comfortable climate at home or at work.


Contact us

(858) 788-1777

[email protected]