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Looking for a replacement actuator

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Ed Lentz_2
Ed Lentz_2 Member Posts: 166
in Thermostats and Controls

I have an older Stadler Viega mixing station. It has a honeywell M7410C1015-OV . It appears to be toast. I say this because I removed it from the valve and powered it up and the piston did not move. So I am looking for a replacement, I understand these are out of production. A replacement might be a Residio MSLF-B030-150. Google doesn't find any in the states. So here I am to see if anyone knows where I can get one of these guys or a different replacement.

Thanks so much

Comments

  • mattmia2
    mattmia2 Member Posts: 16,462

    did you wait long enough for it to heat up? those heat motor actuators take something like tens of seconds to a couple minutes for the wax to heat and move the actuator

  • 109A_5
    109A_5 Member Posts: 3,888
    edited February 8

    Many Honeywell M7410C1015 on eBay.com, most in China. Not sure what the -OV suffix means.

    Seems at least the stroke of the MSLF-B030-150 is different 8mm vs. 6.5mm for the M7410C1015.

    image.png

    https://www.actuacontrols.com.br/files/M7410C1015.pdf

    National - U.S. Gas Boiler 45+ Years Old
    Steam 300 SQ. FT. - EDR 347
    One Pipe System
  • Ed Lentz_2
    Ed Lentz_2 Member Posts: 166

    hi Mattmia2

    I can hear a motor in it running when I put power to it, I thought it was motorized.

    Hi 109A_5

    I saw those on ebay, they are crazy expensive, at least to me. I'll keep looking. Maybe I bought a unicorn for a mixing station, 20 + years ago.

  • mattmia2
    mattmia2 Member Posts: 16,462

    maybe it is motorized but usually those use a heat motor.

  • Ed Lentz_2
    Ed Lentz_2 Member Posts: 166

    This one uses a motor that drives the spindle. I'll try looking harder for the residio part

  • Ironman
    Ironman Member Posts: 7,902

    I’ve used the Rehau actuators several times to replace those motorized Honeywells on the old Viegas.

    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
  • Ed Lentz_2
    Ed Lentz_2 Member Posts: 166

    Thanks Ironman

    Do you remember what models? I am converned with the connection to the injection station, movement distance and power required. I think the connecction is 1 inch and the movement is 1/4" Is Rehau a US company? Not that it matters much just the shipping time and cost.

    Thanks!

  • Ironman
    Ironman Member Posts: 7,902

    As far as I know, Rehau only offers one actuator.

    RE Michel is the largest Rehau distributor that I know of.

    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
  • Ed Lentz_2
    Ed Lentz_2 Member Posts: 166

    i found a replacement / alternative Honeywell actuator on Ebay. And it didn't cost my first born either.

    Thanks all for your help!

    109A_5
  • hanwest33
    hanwest33 Member Posts: 1

    Ed Lentz _2 I am in this same boat! Any chance you can tell me which Honeywell actuator you got? I am trying to find the right part for my Viega basic heating control and they have discontinued it. Thanks!

  • Ed Lentz_2
    Ed Lentz_2 Member Posts: 166

    I found this on ebay. https://www.ebay.com/itm/177763145585?_trkparms=amclksrc%3DITM%26aid%3D777008%26algo%3DPERSONAL.TOPIC%26ao%3D1%26asc%3D20250528145715%26meid%3D175d48d93cba40c1bcf5b8c651f8f2da%26pid%3D102790%26rk%3D5%26rkt%3D10%26mehot%3Dnone%26itm%3D177763145585%26pmt%3D0%26noa%3D1%26pg%3D4375194%26algv%3DRecentlyViewedItemsV2DWebWithPSItemDRV2_BP%26brand%3DHoneywell%26tu%3D01KHV93SKDNDY8EZR9GQVJ60XV

    I haven't installed it but it meets the same specs as the original I have. Price was real reasonable.

    PXL_20260219_004405096.MP.jpg
  • hot_rod
    hot_rod Member Posts: 27,329

    That is a modulating control, you just need an on/ off actuator.

    Pretty much any brand actuator will fit onto that manifold. Most are M30- 1.5 thread now. Some early Wirsbo were M28—1.5 and now they offer an adapter ring to fit the common M30 replacements.

    I doubt Viega actually made the actuator, sometimes you can find the actual manufacturers name somewhere on the actuator.

    So the threads are pretty much all common, there are a few snap on types, also.

    But the difference from brand to brand may be the pin stroke. The wrong actuator could cause the valve to not close completely, or not open fully.

    You could measure the stroke length with a caliper or accurate ruler. Some actuators list that travel length.

    Ideally you find an exact match, but any brand will fit and can be adjusted somewhat on the assembly thread, for instance.

    I have seen adaptor kits available in Europe to allow swapping of actuator brands, basically thread converters or spacer rings.

    Also you don't want to power a thermal actuator without having it attached to the manifold or valve. The thermal "motor" inside can push apart without having something to push against, and limit the travel.

    Screenshot 2026-02-19 at 9.13.24 AM.png
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • Ed Lentz_2
    Ed Lentz_2 Member Posts: 166

    Hi Hot Rod

    From what I have found this is a pretty close replacement, right mounting collar, stroke is 6.4 mm the only issue I can find might be the force. This one is 180N (40.5 lb). Yeah it has been quite a time finding what I did. I am going to install it in the next day or so, wish me luck

  • hot_rod
    hot_rod Member Posts: 27,329

    What destroys actuators more than anything is the pins get sticky from bad water quality. Then the actuators tend to come apart.

    Or water getting into them :)

    You should be able to easily push that pin down with a flat piece of metal, the flat side of your pocket knife or a tough skinned finger,for example.

    If not clean the stem and re-lube the o-rings.

    Screenshot 2026-02-19 at 10.01.51 AM.png Screenshot 2026-02-19 at 10.03.20 AM.png
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • Ed Lentz_2
    Ed Lentz_2 Member Posts: 166

    Thanks for the tip. I can operate the valve pretty easily. No leaks, thank god. My issue is that the new actuator has a different thread pitch! There must be a difference in them from US to Europe? I might try to switch the nuts from the old to the new. Given that this is a mechanical actuator instead of a wax one, shouldn't I see movement of the stem afte a minute or so of running?

  • hot_rod
    hot_rod Member Posts: 27,329

    Perhaps that actuator is made for a specific valve with a special thread? With that floating 24v it is for a modulating control valve of some sort

    All the hydronic manifolds I have seen are 28 or 30 mm 1.5 pitch.

    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream

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