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ERV balancing question

cldlhd | Posted in General Questions on

I’ve been thinking about installing an ERV ( leaning towards the Panasonic  intelli choice 100 ) and I have a question about balancing. I’m planning on keeping my existing bathroom fan, and range hood separate. So my rudimentary understanding leads me to believe that balancing involves basically having the same cfm’s coming in as going out? Or is it based on pressure? So if I have 70 cfm on both intake and exhaust and I turn on a bath fan, hood or dryer is there a way to have the intake side ramp up to help make up for the added air leaving through the bath fan?

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  1. Expert Member
    Akos | | #1

    An auto balance unit such as the on you mention will automatically compensate up to a certain amount of pressure change. If you are talking about reasonably tight house with a small range hood, it should be within the range of the unit. You can look at the blower curve in the spec sheet (P2):

    On boost, up to 0.4" wg the curve is vertical, this means if the overall pressure across the blower is within 0.4", the flow rate won't change at all.

    Keep in mind that it won't increase any flow rate, it will ramp up the blower enough to maintain the flowrate setpoint and keep the unit balanced. So this won't provide any makeup air if that is what you are looking for.

    1. cldlhd | | #2

      Thanks for the link and the info

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