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HRV Controller 3 wire

Shawnnixon1 | Posted in General Questions on

I have a lifebreath HRV connected to a humidistat controller, I ordered the full LCD controller removed the old one only to find out it’s 2 wires but this controller needs 3, what can I do?

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  1. Shawnnixon1 | | #1


  2. jberks | | #2

    Based on the lack of info, Sounds like you'll have to rewire it.

    But before you start tearing down your walls, double check your HRV can accept this controller.

    Feel free to post the wiring diagram of the HRV and the controller. Also some lifebreath units can be controlled wirelessly.


  3. Shawnnixon1 | | #3

    Its a LIFEBREATH 155 Max and controller is the wall LCD controller

  4. jberks | | #4

    It looks like your original humidistat is also supposed to be a 3 wire. So however it was wired before with 2 wire, you can do the same.

    I imagine you have a jumper at the terminal block to get around this.

  5. Expert Member
    Akos | | #5

    I'm assuming the LCD controller also needs 24V power. This means you either need to pull a new 3 wire cable or install one of those thermostat modules. These modules need only a two wire connection between the two sides and provide a full 5 wire terminal set. You can use say the fan control signal for the humidistat control. Google "universal thermostat smart wire module".

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