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Need help w/ Honeywell Prestige IAQ system wiring.

I am in need of some assistance in connecting a Honeywell Prestige IAQ system. I have a baseboard heat boiler with 4 zones (3 for this application) that's located in the basement. There is also 2 AC units located in the attic. See diagram.

The rationale for this system is the ability to use remote temp sensors in the bedrooms which are on a single zone for both AC and heat. Stat 3 utilizes the remote sensor as well due to the size and height of the room. This has worked flawlessly with the commercial stat that was in place prior, but now we are seeking remote accessibility - hence the Prestige IAQ system.

The heating works flawlessly utilizing the TrueZone panel and Wireless adapter. Where I'm challenged is how to connect the AC's to the thermostat. Since my system is wireless using Redlink technology, I have to use the EIM (Equipment Interface Module) or the TrueZone panel with Wireless Adapter to connect to thermostats. How do I connect the AC units? TrueZone panel operates the zone as if they are dampers. Presumably if I run the AC (on) wire from basement to attic, any time the AC turns on the hydronic zone would open. Will the thermostat be able to recognize both the TrueZone and EIM at the same time?

Thanks in advance.
B

Comments

  • GW
    GW Member Posts: 4,691
    I'm familiar with the Prestige, true zons and the EIM. I don't fully understand the layout. You have a grand total of 3 wireless stats connected to one true zone?

    I don't think you can do what you want to do, unless I'm misunderstanding. Generally one stat/EIM handles one heating and or cooling appliances.

    Are you saying you want to run your two ac systems off of the one True Zone? That's a little tricky. You could set up a 24v contactor, and the NO terminals could close your R amd Y of the AC systems.


    Gary
    Gary Wilson
    Wilson Services, Inc
    Northampton, MA
    gary@wilsonph.com
  • bkaushansky
    bkaushansky Member Posts: 2
    Correct. Three stats are currently hard wired to the hydronic heating and control the 3 zones. They are also hard wired to the 2 AC systems.

    My understanding is that I can connect a TrueZone 322 to Wireless adapter so that I can control the 322 via Redlink by 3 different thermostats. That should take care of the heating. I'm challenged by how to link in the AC systems. They can be hard wired to the TrueZone or EMIs.

    I think my solution is to use the TrueZone for stat 1 & 2 with hard wired AC2; and EMI connected to AC1 then hardware that heating zone.

    The way the zones are wired is if the zone contact is closed, the heating system is then turned on and controlled by an aquastat.
  • GW
    GW Member Posts: 4,691
    If you run the ac systems off of the zone damper contacts you need a way to make sure the heat doesn't come on. If you're a control guy it's easy. If not you're in for a fun one.

    You will need to grab either your w or y terminals on the EIM to allow or disallow the heat to come on when you get an ac call.
    Gary Wilson
    Wilson Services, Inc
    Northampton, MA
    gary@wilsonph.com
  • ratio
    ratio Member Posts: 3,616
    I don't think you can link one stat to two different RedLINK devices. What I'd probably look in to first is linking the stats to three EIMs, then hardwiring the EIMs into the AC for cooling & the TrueZONE for heat. Interposing relays might be needed, but IIRC the EIMs have R, Rh, & Rc terminals, might be enough to isolate things.

    Maybe set up the TrueZONE for a heatpump, then you'd have a signal to tell whether the system wants heat or cool. Set it to an O valve (energized in heat), then take the R from the valves through that first, then to the damper contacts. That'd keep the valves unpowered during a cooling call. If you did that you could eliminate the EIMs I think & go with one THM4000. Still look hard at the contacts to make sure everything is properly isolated & that it actually does what it needs to do.

    Interesting problem, thanks for sharing!

  • ratio
    ratio Member Posts: 3,616
    I forgot about the separate AC units. I don't think you can eliminate the 3 EIMs after all. Pull the Rc<->Rh jumper & you should be able to get away with just an isolating relay on the G terminal.