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LIne Set Frost in Winter

as in, leaking refrigerant frost? bec that'd be the only time you'd see frost if it isn't running. you sure it's not a heat pump?


  • Paul MacDougall
    Paul MacDougall Member Posts: 36

    A line set inside our customer's house has frost on the connections to the ac coil and around some of the exposed piping where insulation has come of the line set. I am not a AC guy but I was curious about the situations, Any ideas? Is it a problem or a natural reaction to the severe cold weather we are having in the Northeast. It was about 45 degrees in the crawl space/basement that houses the unit.
  • Joe_70
    Joe_70 Member Posts: 12

    sounds like there mite be a problem the condensor runnig
  • Paul MacDougall
    Paul MacDougall Member Posts: 36
    Dangerous situation???

    No, I checked. The unit is old and looks to be poorly installed, real hack job on all the mechanicals. I am going to recommended they contact a AC pro. Could this me a dangerous situation??? Destruction of property??
  • Matt_67
    Matt_67 Member Posts: 195
    It happens

    Dangerous No. It's simple the refrigerant migrating. The difference between the compressor crankcase heater or winding temperature and the indoor coil temperature as the heating cycles of the furnace changes can make the refrigerant move all on its own. Refrigeration's cool.
  • Empire_2
    Empire_2 Member Posts: 2,343
    rw: very good observation.

    Example: In one of our many installations, with the compressor's (commercial 4 story building) in the basement and the condensers atop the building, we had a problem with ref. condensing on the off cycle during cold weather and liquid would fall to the compressor thus dead headding upon start up. A simple check valve was installed to eleviate the problem.

    Not to say this addresses this problem, but just an observation I ran across.

    MIke T.
  • Compressor lower than condensor

    In your set-up, if you want to save the compressors I would install a solinoid valve and pump-down. This will provide a liquid free compressor on start-up every-time. Well almost every-time there is a few situations than can fool this and in that situation a nice suction accumulator comes in handy.
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