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.

Taco Zone Valve box noise

Options
Peter2
Peter2 Member Posts: 3
I have a Taco ZVC403 zone valve control box. I have 3 zones each having their own thermostat. When a zone calls for heat there is a “LOUD” buzzing noise and I believe it is coming from the zone valve box. What would cause this? The strange thing is it doesn’t happen all the time. I’ve been shutting the power switch (electric) off to the boiler when it does happen. Any help would be greatly appreciated. Thank you in advance. Peter

Comments

  • STEVEusaPA
    STEVEusaPA Member Posts: 6,506
    Options
    It's a relay vibrating, or causing vibration.
    If I were there I'd first do the non-technical, but aware of electricity, 'pushing on stuff' while it's buzzing to see if it stops. I've seen them buzz if the cover isn't screwed on tight.
    If that hail mary doesn't work, it's time to open it up, get a meter and see whats doing.
    Do you have any power stealing thermostats (brand/make/model)?
    steve
    Peter2Alan (California Radiant) Forbes
  • Peter2
    Peter2 Member Posts: 3
    Options
    Thank you Steve. 
    Two of the thermostats are Lux 1500 and the other is Honeywell Home RTH7560E1001. 
    My system is HEAT only. 
  • Alan (California Radiant) Forbes
    Options
    I believe the old Taco ZVC's had replaceable relays. Don't know it that's still the case. If not, you will probably have to buy a new control to make the noise go away.
    8.33 lbs./gal. x 60 min./hr. x 20°ΔT = 10,000 BTU's/hour

    Two btu per sq ft for degree difference for a slab
    Peter2STEVEusaPA
  • Peter2
    Peter2 Member Posts: 3
    Options
    Thank you Alan.