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Community and Q&A

Mold Growth on Minisplit Head

AJ__ | Posted in Mechanicals on

It’s left on a lot in summer and it looks like mold is growing on the diffuser blades. There’s also some pale brown marks on the wall where it looks like a small amount of fluid has dribbled down the wall from behind the unit.

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  1. Expert Member
    BILL WICHERS | | #1

    The liquid running out is probably condensate, water that’s been removed from the air by dehumidification. The stuff on the blades is probably due to moist air blowing which happens sometimes depending on how the cycle runs.

    You can use bleach solution to clean out the condensate pan. Bleach containing cleaners will work on the diffuser, but test the cleaner you want to use on a spot that’s hard to see first to be sure it doesn’t damage the plastic parts. Some cleaners will react with plastics and mess up the finish.


  2. brp_nh | | #2

    Our mini split instructions say to run it in fan mode for a bit after turning off cooling mode, so remaining condensate evaporates. If you're cooling a lot and then just shut it off when not needed, you'll have condensate left that can promote mildew growth and drips.

    Not sure what type of mini split you have, but I found this video helpful when I took apart and cleaned ours:

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