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Circulator runs before/after zone valve opens/closes

ptz3233 Member Posts: 13
Thanks for the wonderful help from this community... you guys helped me find a way to quickly convert my system to pumping away mid-season to alleviate some air issues...
Now I am (possibly unfortunately) very in-tune with the sounds my system makes.

I seem to get a sort of water hammer noise when a zone valve opens... I noticed this is the sequence of events:
1.Zone calls for heat
2.Circulator runs
3.After a couple seconds, zone valve opens
4.Zone valve closes
5. circulator stops running.

Between steps 2 and 3 and 4 and 5 this time seems to just be creating a negative pressure between the circ and the zone valves ... this makes no sense to me as to why the circulator would keep running in this time.

I have a utica 15b with an integrated honeywell control module... nowhere in the documentation is this sequence seem to be configurable. I know the ZV's have end stop switches and it could be a way they are wired that is causing this.

I am wondering if this is some sort of optimization that runs to keep hot water from just sitting in the boiler... but only makes sense in a 1 zone system...

Has anyone seen this before? Hard to find information on this boiler, it seems somewhat uncommon


  • unclejohn
    unclejohn Member Posts: 1,726
    Yes I have. Seems that the people who make the rules don.t know about zone valves. Some boilers have a dial for more or less efficient. Go all the way less. 
  • ptz3233
    ptz3233 Member Posts: 13
    unclejohn said:

    Yes I have. Seems that the people who make the rules don.t know about zone valves. Some boilers have a dial for more or less efficient. Go all the way less. 

    Thanks for your response,

    I can't seem to find any way to adjust this type of setting on my boiler, seems it has an integrated control module made just for this line of boilers... with no good documentation.

    Attached is a picture of the control I have, and the only places in the manual where any sort of settings are discussed - one of which is just some sort of legal disclaimer.

  • Ron R
    Ron R Member Posts: 16
    On a typical installation when a call for heat happens--the zone valve should open first- once it opens, the end switch contacts inside the zone valve should close, which would then send the signal to your boiler control to start the boiler and the circulator. If your pump is turning on before the valve opens you may have some re-wiring to do. If your boiler control has a feature where the circulator runs after the call for heat ends in order to purge the remaining heat out of the boiler--you need to turn that feature off.
    We have found that "banging" sounds and pipe shaking in a zone valve system often happen when a valve with 2 springs in it (Honeywell V8043) close while another zone is still calling---the double spring makes the valve close very quickly and with the pump still running the water slams into the closing valve stopper ball causing the shaking and noise. In those cases we remove one of the two springs for a more gentle closing action of the valves.
    HVACNUT Member Posts: 3,920
    You might want  to contact Honeywell. The control powers the circulator. I don't see how it can be energized before a heat demand, but it might have a built in purge feature when the call ends.
  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 2,170
    edited February 12
    This control will solve your problem.
    It is available in 3, 4, and 6 zone valve models
    Connect the circulator to the EXTRA END SWITCH contacts on this control to provide the circulator operation you desire.

    You can PM me for more information on how this will help.

    Yours truly,
    Edward Young
    Retired HVAC Contractor from So. Jersey Shore.
    Cleaned & services first oil heating system at age 16
  • ptz3233
    ptz3233 Member Posts: 13
    Thanks for the repliess guys, the taco ZVC is something I've considered but it may be a bit of a stretch for me to install that during the heating season .... I just know that there must be some sort of setting to turn this optimization off - The guy on the Utica support phone line even alluded to it - but basically cut me off and told me to kick rocks cause I'm just a lowly homeowner and not a licensed installer... Gonna contact the guy who installed and see if he knows what I'm talking about
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