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Manifold Actuators

I picked up a job that needs some replacement Wirsbo (now Uponor) manifold actuators. There are two Wirsbo manifolds with different actuators. It would help me to identify the actuators part number.

Many thanks.
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


  • Ironman
    Ironman Member Posts: 7,375

    I don't have the part numbers, but the ones on the left are the older wirsbo/Honeywell style. You can use the Rehau style on the right to replace the older style though the older ones are still available from Honeywell. If the Rehau are used, they must be mounted upright on these manifolds. They are much more reliable.

    The old style are micro motor; the new are a heated wax element.
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
  • Plumdog_2
    Plumdog_2 Member Posts: 873
    It can be maddening!

    Honeywell still sells those motorized telestats, but the screw-on collars don't match up with the old Wirsbo manifolds. I tried to swap the collars but I can;t get them off without ruining the little locking ring and stuff. The Uponor 301A (I think) with the correct adaptors will work, but I wish they would produce those motorized ones with the right collars again. I don't like waiting for that slow-motion button to rise! The time required to go through a job with 30 or 40 of those wax eggs and check the end switches is ridiculous!
  • hot_rod
    hot_rod Member Posts: 22,120

    The Caleffi TwistTop would fit. I'd be glad to send you one. Its a actuator that can be manually opened, also. It "makes" the end switch and returns closed when powered if you forget to.

    The threads are usually common, the difference will be the pin stroke and length. It could be the replacement actuator holds the valve open a bit, or doesn't allow it to fully close if the pin is different.

    That gear style Wirsbo was a Sparco design I believe, taken over by Honeywell. You might find some old Sparco inventory out there.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • Thanks, guys!

    I spoke to Matt at Uponor and he gave me a replacement part number A3010522 to replace either actuator.

    I'll purchase more than the owner needs and keep a few in stock at his house for future failures.
    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