Welcome! Here are the website rules, as well as some tips for using this forum.
Need to contact us? Visit https://heatinghelp.com/contact-us/.
Click here to Find a Contractor in your area.

Secondary loop switching realy Buderus GS142

crzoomb Member Posts: 2
How does one go about wiring in a switching relay to shut off the seconday circulator when a call for heat ends and not have it run during the post purge with the main circulator? My concern is dead heading the pump.

Thank you


  • STEVEusaPA
    STEVEusaPA Member Posts: 6,505
    tell me a little more pls

    About your system.  Is your secondary circ serving multiple zone valved loops?  If it's pure primary/secondary, with circs, there wont be any dead-heading.

    Decribe your systems, pics would help.  What kinda equipment, what kind of controls, etc. 

    What's your main boiler control.  You could possible wire the zone circ and the t-stat to a separate relay, but I need to know what you have so we can make sure your main control knows theres a demand, and when it's satisfied 

    The little extra it's running is helping it to eek out some extra btu's, use em or lose em.  Unless you're overshooting the temperature in the zones.

    Or are you hearing a banging from zone valves closing before the circ shuts off.

    There was an error rendering this rich post.

  • crzoomb
    crzoomb Member Posts: 2

    Pipes are banging when zones close. I'm just not sure which terminals to go off from the main board to the relay, are they powered or dry.

    I have 3 zones on the secondary with one Taco 007 and 3 HW focus pro 5000 set for heat hi eff. boilers.

    Thanks for the reply Steve
This discussion has been closed.