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Installation Help

smithmark02smithmark02 MissouriMember

Hello! I am getting lots of conflicting information on my situation from our builder and HVAC company that I'm hoping this community can help me with.

Furnace ML 180UH
Control Panel LZP-4
Old Thermostat Honeywell FocusPro 6000
Heat pump with 1 stage heat with multi zones

I've been told that my Ecobee 3 should be compatible. I have it wired as such

R -> Rc
G -> G
Y -> Y1
W -> O/B
B -> C

The air conditioning worked great over the summer. However, now at winter time we had a situation where it got cold enough that the heat pump didn't switch on which was expected but it didn't switch on the auxiliary heat. We are being told that we need to manually switch to emergency heat on the control panel. However, our builder says the control board should do that automatically.

To make this even more complicated, we sold our old thermostats and I deleted the old wiring photo as I thought it was all working which was my mistake.

Is there a way to wire our Ecobee 3 so we don't have to manually set to emergency heat and also so we can get benefits of heat pump?

Thank you so much for your time!


  • kevinmcckevinmcc Macomb, ILMember

    That looks incorrect.

    Please check your wiring at the furnace. Pictures would help.

    W normally calls for heat. O/B is used to activate the reversing valve on heat pump.

    I would assure B should be connected to O/B and W to W1.

    You probably need to use the PEK to connect C if you do not have more wires.

  • smithmark02smithmark02 MissouriMember

    Thank you so much for the reply. I've included a copy pictures but please let me know if they aren't detailed enough.

    This wiring is to the equipment.

    This picture is the wiring of the two separate zones.

    This is what it looks like on the panel for zone 1
    R -> R
    G -> G
    Y -> Y
    W -> O
    B -> C

    Thanks again for your help!

  • kevinmcckevinmcc Macomb, ILMember

    You have 5 wires, I would think you would need 6 wires or PEK.

    At your zone you should have R, G, Y, O, C, and W which is not connected.

    When your heat pump can not keep up you need to call W for emergency heat.

    The Ecobee should be set to Heatpump with O/B power on cool.

    I am not sure how you are getting heat on AUX mode with no W1 connection.

    Ecobee - Zone 1
    Rc -------- R
    G --------- G
    W1 -------- W
    Y --------- Y
    O/B ------- O
    C ---------C

  • SneakXSneakX MontrealMember

    Seems the two white wires are mixed-up on the last picture. I also agree that a wire is missing to W (use the green spare one).

    Kevinmcc: maybe it activated on low temp lockout only...

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