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Damper control motor

Jim Phillips | Posted in Mechanicals on

I have a 36″ whole house exhaust fan mounted in an attic dormer with a gravity damper. I want to add a damper control motor. Problem- the fan is a two speed, wired from down stairs and the damper motor needs only one input. I think I need a relay to make it work. What kind of relay is required? Thanks.

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  1. GBA Editor
    Martin Holladay | | #1

    I'm not an electrician. There are lots of ways to do this, I imagine. But a current-sensing relay would work:

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