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Community and Q&A

Minisplit on Ice

twoodson | Posted in Mechanicals on

It’s been colder than usual and snowy here as it has been many other place (0 at night, 10 in the day, zone 4a).  This picture is of a 24kbtu Fujitsu -5 unit that pairs with the 24k mid static ducted unit.

This unit worked hard and kept running though it all.  I’m not happy about the way this was mounted on the roof, but it seems to serve the purpose.

There is ice around the bottom of the base pan.  It still seems to be draining well as evidenced by the ice below the unit,  but should I be concerned about the ice on the unit?  I’m sure it was worse last night.

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  1. evantful | | #1

    I think that all looks fine, as long no ice is building up in the pan of the unit itself. I imagine this is all out of the ordinary weather wise for you so this looks perfectly fine for a once every few years kind of situation.

  2. Expert Member
    Akos | | #2

    A bit of ice in the bottom of the pan is not an issue. If this ice makes it all the way up to the coil it can cause it to break.

    Hard to tell from the picture, but if the ice is close to the coil, I would spend some time up there with a heat gun/hair dryer/space heater and get it fully defrosted. A bit of work now to not have to worry about having to replace the unit is well worth it.

  3. twoodson | | #3

    Thanks for the input, all! I figured it probably isn’t an issue, but wanted to ask this informed group. This is the second winter for this unit and I did observe some bent fins at the bottom before this winter... I assume it’s from ice. Minor, but there.

    I had considered, as an emergency option that doesn’t involve me climbing up on a 2nd story roof at 0 degrees in the middle of the night in a blizzard, adding some adhesive mounted pipe heat cable. I could even remotely trigger it. There is an electrical outlet right on the unit. Anyone done this with a unit that doesn’t have a basepan heater?

    1. Expert Member
      Akos | | #4

      I can't see why that wouldn't work. You need some real heat tough. Pipe heater is nowhere near enough.

      Look at silicone drum heaters (McMaster carr has a bunch). You want around 200W to defrost the pan. There are also some automotive block heaters that have similar power that are cheaper.

      Just make sure not to cover the drain hole with the heater.

      1. twoodson | | #5

        Thank you!

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