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Snomas's avatar
Snomas
Explorer
May 21, 2013

Zone 2 won't read on Thermostat

I had a problem w/ zone 2 (rear A/C control) on the thermostat not reading when in Houston this winter and just redid the J11 connections @ the front A/C to rear A/C after recommendations on this site hoping that was the problem. That did not fix the problem. Can anyone tell me where to go from here. Dometic HQ told me it could be a thermostat or a circuit board on the rear A/C.
Class A

5 Replies

  • dougrainer's avatar
    dougrainer
    Nomad
    May 22, 2013
    Snomas wrote:
    Doug, I have not replaced the zone 2 A/C unit. Does the zone 2 A/C have J11 connections in the same place as the zone 1 A/C?
    I have reset the thermostat and get FF after every operation. I have not touched the dip swithes on either A/C unit.


    ALL CCC AC control boards have the same J11 connections. The odds are the modular connections are corroded, more so if you have a Penguin low profile model. Doug
  • Snomas's avatar
    Snomas
    Explorer
    May 22, 2013
    Doug, I have not replaced the zone 2 A/C unit. Does the zone 2 A/C have J11 connections in the same place as the zone 1 A/C?
    I have reset the thermostat and get FF after every operation. I have not touched the dip swithes on either A/C unit.
  • steveownby's avatar
    steveownby
    Explorer
    May 21, 2013
    If you have the 5 button thermostat have you done a reset at the thermostat.
    1. Slide power switch to off.
    2. Press and hold both the zone and mode buttons
    3. While holding these buttons, slide the power switch to on.
    4. When FF appears release the buttons.

    Check to see if the zones are now appearing.
  • dougrainer's avatar
    dougrainer
    Nomad
    May 21, 2013
    You need to check and redo the J11 connections at the Zone 2 AC also. have you replaced the Zone 2 AC or did this problem just come up???
    1. The Zone 2 has the communication cable going from IT to the Front Zone 1 AC control board
    2. The Zone 2 has a DIP switch ON the Zone 2 control board that MUST be set to Zone 2 or it will not read out
    Doug

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