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Triple acting relay

After removing a tankless coil and  installing a separate water heater how do you turn the triple acting into a cold start relay?


  • Paul S_3
    Paul S_3 Member Posts: 1,257
    low limit

    turn the low limit setting all the way down.....or put in a regular aquastat relay.......paul s
    ASM Mechanical Company
    Located in Staten Island NY
    Servicing all 5 boroughs of NYC.
    [email protected]
  • JStar
    JStar Member Posts: 2,752
    edited March 2010
    Depends what make...

     I have a Honeywell Triple Acting Relay. I found the lead wire for the low limit setting and disconnected it (simple spade connector). If you find the wiring schematics, you can find the right wire, or post a model number for the relay and we'll find something.
  • TonyS
    TonyS Member Posts: 849

    I traced out the board and it looks as though eliminating the red wire feeding the bottom of the low limit should be disconnected and capped, then the circulator is now run off of ZR and the burner remains on B1. ZR AND B1 are now only energized when TT is complete but the burner still cycles on the high limit.  Does this appear correct?
  • billtwocase
    billtwocase Member Posts: 2,385
    no that's not the correct wire to disconnect

    That's not it
  • JStar
    JStar Member Posts: 2,752
    I have the same Aquastat.

    Disconnect the blue wire going to terminal B right next to the Differential dial. It's just a stake-on connector that you can pull off. Don't cut any wires.
  • TonyS
    TonyS Member Posts: 849
    edited March 2010
    I set one up today

    If you disconnect the red wire feeding in just below the low limit and cap it(wirenut) that is the only feed that remains hot after the relay is deenergized. The problem is that the circulater terminals are charged off that wire. The high limit side is independent and has its own built in 10 degree differential. The ZR terminal is only energized when the relay is energized as is the B1 terminal except the B1 terminal can be interupted by the high limit. By using the ZR terminal for the circulator, the circulator will be energized whenever the relay is energized(TT call for heat) and the high temp switch will operate the burner but will also drop out whenever the relay is deenergized.
  • TonyS
    TonyS Member Posts: 849
    I am going to try

    removing just the blue wire tommorow. Thanks
  • Big Ed_4
    Big Ed_4 Member Posts: 1,901
    Cold Start

    See I wouldn't make it a cold start ... I would maintain enough temperature to prevent combustion condensing and seal leakage . Drop it down to 120 .. Most coiled boilers are not designed to be cold start like a Buderus ... Even the Buderus Logamatic controls let's the boiler build a little until it powers up the heat zones ...
    I have enough experience to know , that I dont know it all
  • JStar
    JStar Member Posts: 2,752

    Blue wire removed as shown with red box in picture.

    Follow the wires now and you'll see that everything works the way it should in a high limit aquastat.
  • TonyS
    TonyS Member Posts: 849
    These same boilers

    most of them New Yorkers come with a cold start relay when you order them without the coil. After installing a water heater the customers sure dont want to hear that oil burner start again till next winter and just turning the triple acting down doesnt stop it from running.
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