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new heat pump explodes!!! story at 11

The "smoke" that is often seen rising from the outdoor unit on heat pump systems is nothing more than vaporizing water.

When a heat pump system is operating in the heating mode, the outdoor unit becomes the evaporator or "cooling" coil. While operating in thise mode, the outdoor coil will frezze up. This, by the way, is part of normal heat pump operation.

In order to remove this ice, the system goes into a defrost mode, which is a modified cooling cycle. During this mode of operation, the hot gas from the compresor is piped to the outdoor coil. This causes the ice to melt and, during the process, some of the water is vaporized. This is what you see coming from the coil.

All perfectly normal.

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  • bill_71
    bill_71 Member Posts: 46

    my old heat pump never did it, why did my new heat pump have smoke coming out of the top. on a sunday after all checks out just fine and you realize this person has never been in the right place at the right time before. rolling my eyes
  • jim lockard
    jim lockard Member Posts: 1,059
    Had a customer call

    Once and say that the outside fan on the heat pump was not working and that smoke was comeing out of the top. kinda took him back I think when I told him all was well, Be OK then right in front of his eyes the fan started to work. J.Lockard
  • bill_71
    bill_71 Member Posts: 46

    hi proffessor.i was being a bit ambiguous with my post. i was the tech and even though i was explaining the"all is fine" scenario, this person just wouldn't take my word for it and i had to go out and reassure her.......it happened to be 35 out that day and about 70% humidity...lots of "smoke" big fire!!!!!!
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