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HZ432 dual fuel

This seems like a wonderful site, help much appreciated.

I am a homeowner with a Honeywell HZ432 board controlling a heat pump (primary) and an oil burner (secondary, programmed to cut over at 25 degrees). The heat pump is not coming on at all - the oil furnace is responding when there's a call for heat, though the outside temp is 38 degrees. When I run through the configuration on the panel, I notice DUAL FUEL OPERATION is set to NO. That seems wrong - should I set it to YES?

Comments

  • 109A_5
    109A_5 Member Posts: 1,680
    National - U.S. Gas Boiler 45+ Years Old
    Steam 300 SQ. FT. - EDR 347
    One Pipe System
  • checkscher
    checkscher Member Posts: 3
    Thanks for your help. I think all these settings assume I have already chosen "DUAL FUEL OPERATION" in the basic settings. So would you suggest that I do that- although the installer didn't? (It seems the installer is figuring this out as he goes, too, but at least he gets to talk to Westinghouse tech support.)
  • HVACNUT
    HVACNUT Member Posts: 6,334
    Show the zone panel wiring. 
    Show the thermostat wiring. 
    Is R on the Equipment side jumped to Rh and there's a separate isolation heat relay, or is R and Rh is separate? 

    Outdoor sensor is in the shade on the north side?
  • 109A_5
    109A_5 Member Posts: 1,680
    Hello @checkscher,
    I would not assume the Basic configuration does anything to resolve your particular install situation.
    DUAL FUEL OPERATION may not guarantee which Dual Fuel Changeover or other option(s) are best for your situation. I would review all the settings Basic and Advanced. If you change something and save it, write it down so you can change it back if needed.

    I think I also would verify the electrical connections to the HZ432 and both heating units work as expected independently of the HZ432.


    National - U.S. Gas Boiler 45+ Years Old
    Steam 300 SQ. FT. - EDR 347
    One Pipe System
  • checkscher
    checkscher Member Posts: 3
    My conclusion from these very helpful comments is that this is a lot more complicated than I had hoped, so I should probably not mess with it; I need to trust my installer. But I greatly appreciate all your advice, which will help me in identifying someone I can trust!
  • ratio
    ratio Member Posts: 3,791
    There's lots of ways to make a dual-fuel setup work, not all of which use the zone panel options. Without poking around it's hard to know which method your installer used.

    That said, if the heat pump never heats, that doesn't sound right—but there are lots of opinions on changeover temps. Perhaps give your installer a call & ask when you should expect to see the HP heating.