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Boiler relay board making noises

klin816 Member Posts: 2

I have a gas 2 zone boiler and when A zone's thermostat turned on, everything runs smoothly but when B zone's thermostat turned on, sometimes, caused the small relay boxes on the relay board to make a fast clicking sound, which turns the boiler on and off. What's the problem? Do I have a bad relay board? Wrong wiring between the thermostat and the relay board? How can I solve this issue? Are there other causes to the issue? Thanks!



  • Docfletcher
    Docfletcher Member Posts: 483
    edited January 2019
    First thing I'd do is swap the relays to see if the problem moves to Zone A. If it does the relay is the problem. I would replace both relays as a matter of course. I am not a pro.
    rick in Alaskakcopp
  • Jamie Hall
    Jamie Hall Member Posts: 20,422
    Also check all the connections and wiring -- and thermostat. If you are losing signal voltage anywhere along the line that can cause the problem.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • hot_rod
    hot_rod Member Posts: 18,195
    what's the brass looking dohickey at the bottom?
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • rick in Alaska
    rick in Alaska Member Posts: 1,396
    Current relay??
  • klin816
    klin816 Member Posts: 2
    @Docfletcher I can try swapping the relays but I did change a new relay for Zone B but it didn't do anything.

    @Jamie Hall Do I call an electrician or a heating repair guy to check the wiring? I don't have any knowledge about a boiler.

    @hot rod_7 I have no idea tbh. This is the setup when I bought the house.

    @rick in Alaska What do you mean by "Current relay"?
  • Jamie Hall
    Jamie Hall Member Posts: 20,422
    That's a good question, @klin816 . Ideally, either one should be able to check that you are getting the correct voltage at the relay -- probably but not certainly 24 VAC -- and then, if you are not, track down which wire or connection or other device is causing the problem. Ideally. In practice... perhaps a really good electrician with some imagination is the better bet, but I wouldn't want to lay odds on it either way
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • Docfletcher
    Docfletcher Member Posts: 483
    edited January 2019
    If you get chattering when both zones are calling you can try...
    Turning zone A off and have zone B call for heat. Does it chatter now?

    HVACNUT Member Posts: 4,858
    Is the thermostat for zone B heat only, or A/C also?
    Nest thermostat?
    On the Argo board does the zone B thermostat wire go directly to the thermostat or to an air handler or relay first?
    With the slot screw terminals you can tell it's an old Argo and the problem could be internal.
    Most times I get a call for a chattering cube relay, its usually a separate 24v source butting with the transformer in the zone board.
    JUGHNE Member Posts: 10,278
    Could the circulator wiring run thru the current relay?
    Seems to be the only thing to draw enough current to activate it.
    T-stat does a relay to start pump, current relay starts boiler??
    Seems pretty strange if that is the case.
    EBEBRATT-Ed Member Posts: 13,101
    Turn zone A stat down so it does not call and try zone B by itself and see how it works.

    If it still chatters, Disconnect both thermostat wires for the offending zone B. Connect the two thermostat terminals with a short jumper wire and see if the relay chatters then.