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Honeywell HZ432 damper motors run continuously

I have a honeywell HZ432 that I put in myself. I also had to replace two damper motors around the same time. The old system was a Carrier Comfort Zone 2, so I replaced everything including main board, two damper motors, four thermostats, and added the extra items to make it all internet connected.

The question I have is, I replaced the dampers with a KMC MEP5233. They seem to work just fine and have for years, but I notice that you can hear the little motor running all the time. It seems the HZ432 powers the damper continuously, whether it is open or closed. My understanding is that it was supposed to stop power after opening or closing, but that is not the case, nor can I find any info on that in the manual. It is either power on/power off, or wiring it for power on/spring close. My dampers have no spring.

Any input would be appreciated!

PXL_20250507_161122144_Original.jpeg PXL_20250507_161215515.MP_Original.jpeg

Comments

  • ratio
    ratio Member Posts: 3,988

    No the Honeywell panel doesn't shut off the dampers once they're positioned. They're basically fed from a form C relay contact, they either make the "open" contact or the "close" one. The TrueZONE zone damper actuators are spring-open power-closed, as soon as the power to them drops they wind closed.

  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 10,470
    edited May 7

    The KMC damper actuator is not on the list of the Recommended Damper Actuators for the Honeywell HZ432

    Screenshot 2025-05-07 at 2.51.11 PM.png

    The manual for the KMC actuator model that you have installed is needed for me to see if it is compatible. Do you know the actual model number of the KMC actuator so I can look up the actuator functionality? Or if you happen to have the manual for your damper actuator, that would be helpful. 

    The thermostat that you are using would also be helpful in how the dampers get connected to the system. As I understand the Honeywell HZ432 when connecting to the power open power closed type damper, there is 24 VAC power to the M1 and M4 terminals the entire time there is a call for heat. That means the damper actuator needs to have a switch of some type that will cut the power to the motor once it reached full open.

    Your KMC actuator does not look like it has that function built into the wiring logic of the actuator. So your KMC motor will be powered the entire time there is a call for heat. It may not be compatible with the Honeywell HZ432.

    Edward Young Retired

    After you make that expensive repair and you still have the same problem, What will you check next?