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Problem: Please help me understand what this warning means on my AC?

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Problem: Please help me understand what this label warning means that is attached to the outside of my air conditioner? “Warning…never stop the cooling system by shutting off the main power. If the main power to your air conditioner is ever disconnected for more than three hours, turn off the thermostat. Then wait for at least three more hours after the power has been restored before turning the thermostat back on. Failure to follow this procedure could result in damage to your air conditioning system”

Answer: Yes sir, I know exactly what you are talking about on the warning not to turn your air conditioner on for 3 hours after the power has been off for more than 3 hours. This is a manufacturer’s warning and quiet honestly not many people abide by it. The warning is there to prevent the compressor from possible valve damage that could occur if any liquid refrigerant has migrated, and is sitting inside the compressor. The compressor is made to pump a gas, not a liquid, and if any liquid refrigerant has migrated into the compressor during the power off period, then when the compressor is started back up the compressor could try to pump the liquid refrigerant and bend the valves, thus ruining the compressor. Many of the compressors have heaters in them, either external or internal that boil the liquid refrigerant off when power is restored. They recommend waiting three hours to make sure all the liquid refrigerant is boiled off. Most people do not abide by this, but if you want to make sure you do not damage your compressor it would be a good idea to wait the 3 hours. Below we have a real good informative YouTube video made by DrZarkloff which explains how to install a compressor crankcase heater. Please remember that the compressor crankcase heater is used to boil any liquid refrigerant off that is sitting inside the compressor. The compressor is not made to pump a liquid, but is made to pump refrigerant gas. Thanks to DrZarkloff for making this informative video. We hope this will help answer your question. If you have any other questions please feel free to email us at: or comment below.  God bless you and your family.

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