Price to have GRUNDFOS pump changed on manifold

[Dan Robinson]

Not run of the mill.

 

[Dan Robinson]

You and I both work in some big gaffs.... I can't think of any client in such a place that would be bothering a diy forum.... .

Back next week to do phase 2 of that one I mentioned last month. Hope @dilalio is well braced Hedge to run the rest of the pipes across the basement driving range

 

[dilalio]

Back next week to do phase 2 of that one I mentioned last month. Hope @dilalio is well braced Hedge to run the rest of the pipes across the basement driving range

Oh $hit! Sorry @Dan Robinson, didn't I notify you? I'm the plumber who eventually found my £72m winning lottery ticket, behind the sun visor of my van!
I'm in Australia, last minute thing, whilst my new house is being built... complete with fishing lake in the basement

 

[Gasguru]

Gasguru is talking crap.
Underfloor heating needs a higher capacity pump due to the resistance of pumping through multiple loops potentially say 1000 metres of underfloor pipework.
The larger inlet pump of a 25/60 gives more ommph than a standard 15/60 the inlet port being 50 % smaller.
The OP underfloor system is relatively new installed 2017 and i would imagine just needs correctly venting and balancing. It is worth noting those later manifolds have a built in filter on the flow. Polypipe put the filter on as people kept putting underfloor on dirty systems which can foul up the flow meters.
I can only see 1 flow indicator in photo. 4 ltrs/min far too fast !!
Normally rule of thumb 1-1.5 ltrs/ min

Take a look at the Grundfos site and read the performance curves for the 25/60...you will see that despite having a nominal 25 sized port it makes no difference compared to the nominal 15 sized port. How much headloss do you think there is across the very short distance of the pump inlet and outlet ports? It's negligible. Of course the documentation could be incorrect but I've seen exactly the same results when comparing other "higher spec" pumps...they're made out to be better performing by having a larger port size but reading the specs that isn't bourne out.