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Cold-Weather Performance of Mr. Cool Ductless Minisplits

kieran973 | Posted in General Questions on

When people lament the poor cold weather performance of Mr Cool ductless units, is this because they only maintain 50-66% capacity at sub-32F temps, or is it because the published cold weather specs are themselves not accurate?

For example, the 18k btuh DIY Mr Cool ductless unit: according to the ASHP specs, it puts out 15,163 btuh at 17F and 12,357 btuh at 5F.!/product/30947

In the real world, does it actually put out these btuh at those temps? Any reason to believe that it doesn’t? Anybody with experience using these as your primary heat source at those temps? I’m in climate zone 5, 99% design temp is 11F. Thanks.

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  1. walta100 | | #1

    Unhappy buyers tend to be more vocal than happy buyers so you have to take reviews with a grain of salt.

    Since the manufactures do not do the install they have little control over the final product.

    I highly doubt any manufacture would risk faking the number filed with the government. I think the ASHP numbers are from independent laboratory testing. With that said VW got away with faking it for years.

    My Rheem heat pump heats my home down to 6°F with the strips locked out.


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