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HZ432 wiring question

Hi All, My first post. Thanks much to the admins for making this site possible. I live in a remote area where service is difficult. Thanks again. I have an FHP(Bosch) Aquarius II Geo thermal System, Model # AP071-1HZC, S/N 3540-103-TW0001-T111M40287. Controlled by a 4 zone Honeywell HZ432. My question is this. Can the 432 fail by commanding the damper to open when it should be closing? Or would this be a damper failure? Can it be wired incorrectly?
The zone in question has a wire inserted in M4, which apparently is not correct?
Any help appreciated. Just starting on this journey.



  • Jamie HallJamie Hall Member Posts: 12,843
    Here's the manual...
    If you are looking at a power open/power close damper, M4 is the connection to power the damper open. Is it possible that the wires to M4 and M6 got swapped? On the other hand, if it's a spring open damper, there shouldn't be a wire on M4... so where does that wire go?
    Br. Jamie, osb

    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England.

    Hoffman Equipped System (all original except boiler), Weil-Mclain 580, 2.75 gph Carlin, Vapourstat 0.5 -- 6.0 ounces per square inch
  • jetroosterjetrooster Member Posts: 5
    Its an ARD8TZ Power Open Spring Close damper. Here's the entire HZ432 Board.

    Notice Zone 4 also has a wire inserted in M4. The tech removed one wire from the malfunctioning damper and said must need a new Zone board. Seems like it's simply miswired to me. Is there any issues, if I trace the wires and connect the dampers per the installation manuals, (M1 & M6, all power open/spring closed dampers) ?
  • jetroosterjetrooster Member Posts: 5
    It goes to this damper, you can see where the tech removed the red wire from M6

  • HVACNUTHVACNUT Member Posts: 3,349
    It's not power open, spring close.
    It power close, spring open.
    Terminals 1-6 on the board. 4 is not used with your damper.
    When another zone is calling, the damper in question should have 24v to 1 and 6 and should close. All dampers should be open when there's no demand from any zone.
    (No 24v, spring open)
  • EBEBRATT-EdEBEBRATT-Ed Member Posts: 7,038
    Sounds like @HVACNUT nailed this. Knowing the equipment will lead to fast and accurate troubleshooting.

    Their are other ways to troubleshoot for others (like me) who are not familiar with the equipment. You could disconnect the damper motor and power it from another sourse to determine it's action
  • ratioratio Member Posts: 2,426
    My experience with that style of actuator is that they're generally flapping in the wind in any case, they just can't seem to close off against more than a half-inch or so. There'e no real upgrade path either; easiest thing to do is replace the damper so a standard actuator can be installed.

    I refuse to use them at work any more, but the sales critters keep selling them anyway, they are half the cost of my method after all. Also, we sell TrueZONE as a value engineered replacement for VVT systems.

  • jetroosterjetrooster Member Posts: 5
    Thanks guys, the tech who removed the wire, said the damper was being commanded to open, when it was supposed to close. Wants to install a new HZ432. I am going to troubleshoot this weekend, wire properly and see if that fixes it. I also, read where this damper can be field modified to operate in the opposite direction, power open, spring close. I will check to see if somehow they screwed that up. I seriously doubt its the 432.
  • ratioratio Member Posts: 2,426
    Pull the actuator off the damper shaft & watch it to see what it does. It seems ...unlikely... that the actuator somehow got reversed, either mechanically or electrically, by itself. With several zones and a bypass in play, the duct static pressure might not be too steady, & can be blowing the damper open one minute and letting it spring shut the next.

    I really don't like those things.

  • HVACNUTHVACNUT Member Posts: 3,349
    I've never used those dampers personally but I was helping my neighbor via texts and pics for trouble he was having at his 2nd home. I downloaded the manual and it can only be spring open.
    The lever on top is how much bypass you want, if any, when it's in the closed position.
  • jetroosterjetrooster Member Posts: 5
    Thanks Guys. Rewired to correct terminals, works perfectly! Think the guy was trying to sell me a $250 board for $1000 (price he quoted for replacing the HZ432) :#:#:# These guys bought out the original installer and are terrible to deal with.
  • HVACNUTHVACNUT Member Posts: 3,349
    @jetrooster. No pricing is discussed here but I'm glad everything worked out.
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