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Community and Q&A

ERV in Cold Wet Climate

christopherramos | Posted in General Questions on

Hi everyone. The climate here in Southeast Alaska is notoriously wet. Our outdoor relative humidity is ~80% year round, and our 1% Cooling and 99% Heating temperatures are 69F and 19F respectively.

What effect would an ERV have on indoor humidity levels in such a wet climate? And would special precautions be needed to prevent condensation? I am particularly concerned about exhausting bathrooms.

I’ve seen lots of discussion on ERV’s in cold & dry climates, but none for cold & wet climates.

Thank you,

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  1. matthew25 | | #1

    ERV's will outperform HRV's in humid climates all else being equal. Being so cold, there is a possible chance of ice forming on the inlet or inside the core. I think there are plenty of threads about this already. I believe the newer models do a better job of resisting freeze but it could still be a possible problem.

  2. Expert Member
    Akos | | #2

    Cold air doesn't hold much moisture, so when you take that 80% RH cold air and warm it up to room temperature it will be very dry.

    Winter here tends to be pretty high RH as well, currently 32F and 70% RH outside. My ERV works just fine and if I over-ventilate, it will still reduce the indoor humidity bellow comfortable levels.

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