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Dual zone: Zone 2 only works when Zone 1 is running


We recently moved into a condo which has dual-zone thermostats. I've noticed zone 2 in the second bedroom only runs when zone 1 is running. If zone one is set at 68 (our ideal temp) and the room temp is 68, zone 2 doesn't run. The problem is the second room can get down to 64 and never run unless zone 1 is. We have the zone 2 thermostat set at 74, but it's currently just 66 in the room. If I kick up the temp in Zone 1, then zone 2 kicks on and it heats up, but that often means keeping the temp in zone 1 to 72. This seems very weird to me and I don't know what the fix is. I've removed and re-attached the thermostat from zone 2 but nothing changes.

The condo runs off a central HVAC system, so there is no furnace in the unit itself.

The association wants to charge me to have maintenance take a look at it and I'd prefer to avoid that if I can.

Any ideas?


  • Paul48
    Paul48 Member Posts: 4,469

    to your neighbors. Maybe all the units share the same problem?
  • Empire_2
    Empire_2 Member Posts: 2,343
    Zone problems

    If I am correct, you have a warm air heat and cool system?  If in fact it is zoned, there are quite a few manufacturer products available.  It could be anything including but not limited to:  Since most dampers are power closed:

    -Failed relay, Disconnected wire, bad damper linkage, Etc...

    Almost sounds like zone #2 is always open and only gets conditioned air when zone 1 calls.  Definitely needs to be looked at.  Ask your maintenance dept if they installed it.  If not, call professional.  This is not a guessing game.

    Hope this helped.

    Mike T.
  • tim smith
    tim smith Member Posts: 2,544
    Re one zone only works when other is on

    I am betting on bad end switch on zone damper or zone valve depending on whether water or air.
  • Nstino
    Nstino Member Posts: 3
    Re: Dual zone: Zone 2 only works when Zone 1 is running

    Thanks for the responses. I have checked with a few neighbors but they are not having problems.  I'll see if I can chat with a few more. It is a warm air heat and cool system.

    I agree it sounds like it might be a damper issue and might be best to call a professional. If it's more than replacing a thermostat then it's out of my league :-)

    The units were built six years ago and we just got a new management company and they claim to not know anything about heating issues.

    I'll let you know if there are any updates.

    Thanks again.
  • Empire_2
    Empire_2 Member Posts: 2,343

    It's so nice when someone such as yourself responds back and offers updates.  Often times, we never even hear any reply and it's almost like the questioner vanished.  I thank you an behalf of HeatingHelp.Com.  I know the personnel here work hard and use their own time to simply help others with response to questions.  The founder of this site Dan H. set up this help site for just that purpose.

    Thank You;

    Mike T.
  • Big Ed_4
    Big Ed_4 Member Posts: 2,238
    Single Zone or slave

    Either you have only a single zone with a dummy or disconnected thermostat or your second problem zone is slaving off your main zone with incorrect wiring . You would need to call in a tech ...
    I have enough experience to know , that I dont know it all
  • John Mills_5
    John Mills_5 Member Posts: 946
    blower somewhere

    Gotta be an air handler or heat pump somewhere to serve your apartment. Beyond that they could have typical zone panel and dampers. Might look in closets and see what you find. A picture of the setup could help us help you. 
  • Nstino
    Nstino Member Posts: 3
    sort of update

    Thanks for all the suggestions.

    I haven't been able to call out a heating expert to look at it yet.

    The weird thing is that it has been running just fine now, even when zone 1 is not running.

    I've had zone 1 set to 67 (it seems to always be 70 anyway) and zone 2 to 69. I've noticed for just the past week that it's been running and pretty consistent at 69.

    It's all a bit strange.
  • billtwocase
    billtwocase Member Posts: 2,385
    sounds like

    you have a bad Trol-A-Temp actuator
  • Saverio DeLuca
    Saverio DeLuca Member Posts: 5

    Sounds like a possible existing problem from the initial installation. Unfortunately the only practical fix appears to be hands on service for what may be a wiring problem or defective control. The most practical approach in solving your problem can be to ask the management company, the name of the company who originally installed the units for the complex. You'll probably have to pay a service call charge however, the original installer is the one most likely to be the most familiar with the installation and they may even have had this same problem in one or more other units in your complex. Therefore, they may likely go right to the solution (maybe even knowing the problem and solution before they arrive) saving you repeated trial and error service calls and repair costs.

    Like to know how it works out for you.
This discussion has been closed.