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Wirsbo TruFlow Meters used with (older) valved manifolds

moltenmetal Member Posts: 5
OK, I'll bite: what's SOOOO much better about the new manifolds, that makes them worth the (significant, to me at least) extra $$$ per circuit? I'm not adverse to paying more money for more or better function, but as you said- flow is flow, right?

What I was worried about was flow profile on the way into the valved manifold, making the TruFLOW units bounce around rather than giving a steady reading proportional to flow. Sounds like there's no problem with that- thanks a lot for your advice.


  • moltenmetal
    moltenmetal Member Posts: 5
    Wirbo: TruFLOW meters on (older) 1.25\" brass manifolds

    Hi All:

    Based on the distributor pricing I've been given, there's a fair bit of savings to be had if you can use the (older) 1 1/4" Wirsbo (Uponor) brass manifolds but using the newer TruFLOW flow/temperature units with them. The newer TruFLOW manifolds are a fair bit costlier for a basic set-up.

    I put a call in to Uponor, who gave me the stock response of, "Well, the TruFLOW flowmeters are only calibrated to work with the TruFLOW manifolds, so we don't guarantee it". If I had a few of these laying around I'd simply try it out, but unfortunately I don't. Considering the application is simple loop balancing, all I need to know is that the flowmeters work in relative terms- the absolute calibration doesn't make any difference to me.

    Anybody out there tried this out and found that it works?

    Thanks in advance for your help-
  • Yup.

    It works. Got to say, the new manifolds are sooooo much better than the old ones. Flow is flow. If you can hook it up it will work (within its range) regardless of what it's attached to. I've used them without the manifold at all with great sucess.

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  • They're shiny ;-)

    I feel that the tru-flow manifolds are of much better quality and design. The balancing mechanism is much easier to work with than the other. I've had problems with the old style plastic keys (caps inverted) stripping out and the stainless pins would keep corroding and breaking off inside a couple of systems that were dealing with water quality issues. The retainer and washer would then end up getting pulled into the suction side, eventually finding its way to the circs volute. They (new manifolds) come pre-assembled and bracketed. I find this a big time saver and the hanger/bracket is much more sturdy compared to the flimsy plastic retainers used on the old school hanger. I believe that Uponor will soon be phasing out the old style manifolds. I really like the Ipex and Calleffi manifolds even better than what Upanor presently offers. It seems the really nice manifolds are coming from Italy these days.

    I'm not exactly sure about the "flow profile" causing any problems, but I've never seen these temp/flow meters bounce around when being used in applications other than being attached to the Tru-Flow manifolds.

    Hope this helps.

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  • Old style manifolds

    Beware of the so-called stainless steel pins in the old manifolds. They are not all of stainless steel and can corrode causing major problems. Ask them what grade stainless steel the pins are.

    They (Wirsbo/Upanor) have been very helpfull in replacing defective materials but not so forthcoming as to telling us why these major failures have occured. They prefer to just move on and sell another OEM- Mfgs. manifold. Can't say I blame them. Those Hunneywell manifolds were loaded with problems from the start. They aparently could not verify specific materials. Too bad.

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  • Tim Doran
    Tim Doran Member Posts: 208
    What Major Failures?

    Aside from the one job that your were involved in, which had a significant electrolosis problem what major failures are you aware of? Please list them here for all to see.

    Tim D.
  • Tim Doran
    Tim Doran Member Posts: 208
    Flow Meters

    The only issue with the flow meters on the cast brass manifolds is the depth of the seat area. The cone on the flow meter is cut a bit longer and may cause seating problems.

    Tim D.
  • The list


    There was no evidence of electrolysis on the job you speak of. This was suspected by all but never proven by anybody. I had the regional rep visit once. Never heard from him again. Sent about 30 LBS of brass manifolds back to Wirsbo for testing. Never heard back from anyone. Keep in mind this was an orphaned system. The problem as stated above (we believe) was with the water quality from the city’s deep well. Chloride levels were very high but within limits of potable water systems in the Commonwealth. I had hoped to have cooperation from the factory to find out exactly why these problems were happening but unfortunately my vigor was met with major resistance from the bottom up. The composition of these (stainless steel) pins could never be verified by anyone at Wirsbo/Upanor. I spoke with way too many people includint the metalurgist (all said they could help) and all of a sudden, I’m being told by my Rep firm to: “just let it go Gary.” That’s exactly what I did. I simply moved on.

    To list the failures I’ve had with the cast brass manifolds; I’ve had brand new manifolds that leaked through sand-holes in the castings. I’ve had stripped actuator threads that couldn't hold a pressure test. On many systems I’ve worked on I’ve seen a loss of glycol fluids seeping through the factory seals on a great number of these manifolds. These bluish/greenish manifolds are now replaced with the TruFlow or other brands because I know they are just not worth fixing. Scrap brass is worth more to me than the postage I've spent to send them off to Wirsbo/Upanor when I allready know that I will never hear back from them WRT the problem at hand.

    No sour grapes here. This is just an observation and recommendation to someone who asked a question. The new TruFlow manifolds have been awesome so far. Isn't that what progress is all about?

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  • Ted_9
    Ted_9 Member Posts: 1,718

    Gary, what do you think of the Caleffi radiant manifolds?

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  • Ted,

    As I stated above, I really like the Caleffi. As far as manifolds go, it seems to me that all the good ones are coming from Italy these days:-(

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This discussion has been closed.