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    Wirsbo zone valve (9 Posts)

  • Mark7 Mark7 @ 9:41 AM
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    Wirsbo zone valve

    I have a 1" Wirsbo Uponor valve, not sure of the model, but may be a A3070526. I found these numbers on a similar looking valve I found doing an internet search, but cannot find any model numbers on the valve. There is a green stripe on the top and the bottom of the front of the valve, if that helps identify it.
    My question is can I troubleshoot this on a bench with a plug in 24 volt transformer? I think something might be wrong with the end switch. When the bedroom calls for heat, the boiler (wielMclane CGs-4) with a 1107-1 Integrated boiler control snaps in and out and sounds all crazy. Shutting down the t-stat stops the control from acting goofy.  I took off the actuator and thinking to hook up 24 volts to the motor leads and see if the end switch closes, or would I hook up to the end switch and see if the motor opens the valve? The actuator shows continuity through the motor and 22ohms. I just want to be sure I got this right and not be throwing parts at this. Any suggestions and advice would be greatly appreciated. Thanks
  • decoy86 decoy86 @ 10:41 AM
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    Sounds like the end switch is bad or going bad.  I would replace this actuator with the thermal version  A3010522.  It is about $25 cheaper and works better. 
    To test the end switch you will have to actuate the motor and then ohm the yellow wires. 
  • Mark7 Mark7 @ 11:04 AM
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    Thanks for the response

    Thanks for the response, but I need to be sure about this. The yellow wires are the motor. Would I hook up the transformer to them, to activate the motor open and check the red ones( the switch) to see if I have continuity?
  • Dave H Dave H @ 1:43 PM
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    Test a Wirsbo Zone Valve

    Exactly that, and yes the endswitch contacts do get a little goofy when it starts to fail.
    I would replace with the thermal style, less moving parts......

    Dave H.
  • decoy86 decoy86 @ 11:09 AM
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    Go to this link:  it shows a picture of the Actuator
  • Mark7 Mark7 @ 7:29 AM
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    Thanks for the advice fellas

    It turns out the end switch is kaput. Now the next thing, will this thermal version actuator that was mentioned fit on the valve, or would the whole thing need replacing? Thanks again.
  • decoy86 decoy86 @ 8:46 AM
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    Thermal Actuator

    The thermal actuator is an exact replacement.  Just unscrew the old motorized actuator and unhook the wires.  The new thermal actuator comes with a plastic ring that screws on the manifold (make sure the ring is tight).  Just snap on the Thermal actuator and hook up your wires (same colors as your old actuator). 
    Link for Thermal Actuator  A3010522
  • Mark7 Mark7 @ 10:13 AM
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    Thanks again

    I appreciate all the help. What a great forum.
  • decoy86 decoy86 @ 11:22 AM
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    The thermal actuator has approx 3-5 minute delay before turning on so don't freak out when you don't see it come on immediately like the other type actuators.  When it full on the middle section of the thermal actuator is raised up.
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