Replacement circulation pump concerns

[diydavidw]

Hi. My Parker 15-60 130 pump has been running fine for 7 years at its highest speed in my 19 radiator/ Greenstar 30 CDI Classic vented system. The pump has recently developed a knocking sound when hot and working hard (disappears on speed 2) but this is not fast enough for my bungalow-with-basement layout. Bleeding the pump had no effect so I suspect it might be on its way out and am considering upgrading to a grundfos UPS3... but I have picked up that these pumps can give problems through being too powerful or have unsatisfactory proportional settings? Any comments? Might I be better with a Salus 100A or 200A which also have auto pressure facility (also much cheaper!) and DAB Evostas seem popular?
I have TRVs on the larger 11 radiators.
Cheers
David

 

[ianmcd]

you would be better finding the cause of the knocking sound, most likely a TRV, if it is, the problem will still be there no matter which pump you fit

 

[diydavidw]

Its definitely the pump, Ian. Probably worn bearing as its a cheap Grundfos clone... but its done 7 years so can't complain!

 

[BlueLoo]

Had exactly the same noise with my 15 yr old pump.
The bearings go and end play causes havoc.

Modern pumps are stronger so a new one might not be a bad idea regardless.

 

[diydavidw]

Any views on relative merits of UPS3 vs. Salus 200A or DAB Evosta 2 or 3?

 

[BlueLoo]

I have the evosta 2.

Works great for me. It's a strong pump and easy to set and mount.

No idea about reliability as its only 6months old.

Edit: check your pump curves.

 

[Exedon]

The Dab evosta 3 is a really good pump we use nothing else for domestic pump replacement. Also use there commercial pumps.
Dab is owned by Grundfos so why pay Grundfos prices?

 

[diydavidw]

Thanks folks. Great help.