Circulation pump replacement.

[darren6645]

I've been having a few issues with my heating (covered in another thread ) currently circulating x400 around my system but when I drain and flush next week I'm going to take the opportunity to remove the head from my pump and check if it's ok, turning freely, nothing broken from impellor, play in the bearing any obstructions is that correct? Any tips on what to look for or tests I can do to prove its good or bad would be appreciated.
If it's on its way out I will change the head. I have attached images below, 1st (blue) the pump in question and the others are possible replacements, there's quite a difference in price from grundfos, which I don't mind paying but wondered if these will replace the existing head an if so does anyone have experience of these pumps and they're quality/reliability or are they that price for a reason?

 

[ReJect]

I can’t say for sure, but there are some very cheap circulating pumps which are Grundfos clones and I suspect cheap Chinese? made. Come with different brand names.
They tend to fail or work only partially.
That last pump looks like one of those cheap type.

 

[Mottie]

That last pump looks like one of those cheap type.

The website on that pump refers to a swimming pool manufacturer, not a heating pump one.

 

[darren6645]

I can’t say for sure, but there are some very cheap circulating pumps which are Grundfos clones and I suspect cheap Chinese? made. Come with different brand names.
They tend to fail or work only partially.
That last pump looks like one of those cheap type.

I did think that but thought I'd ask. I'll try and source a grundfos head if I need to otherwise a full pump change.
Any advice on identifying failing pump, should it spin free by hand etc. I did read somewhere about removing the bleed screw and inserting a screwdriver, if pump can be stopped it's on its way out?

 

[ianmcd]

The Grundfoss pump head @ £63 will fit, forget the rest, yes if you can stop the pump with a screwdriver then the pump is weak

 

[darren6645]

Removed bleed screw from both pumps today. CH pump runs on setting 2 with reasonable amount of pressure I can stop spinning with screwdriver, on setting 3 no chance so this looks ok, I think?
HW circulation pump currently on setting 3 (due to cleaner in system and noise when boiler at max) , can be stopped with similar amount of force on screwdriver and if switched to setting 2,can be stopped quite easily, so I'm guessing it's on its way out. Both spin freely with pump off and screwdriver in.
Are these Grundfos pump heads old models? Plumbers merchants and Grundfos only seem to show the new red pump head. Don't want to spend a fortune if not required but don't want to fit old inefficient parts either.

 

[ianmcd]

just noticed that the pump head in your pic is low energy so probably wont do for a replacement of what you have

 

[darren6645]

just noticed that the pump head in your pic is low energy so probably wont do for a replacement of what you have

Ahhh damn, I had noticed that but thanks Struggling to find just a head for reasonable price, the ups3 is cheaper but would be a full pump change.

 

[ianmcd]

https://www.ebay.co.uk/itm/Vokera-2...456347?hash=item3f3ebc215b:g:hMgAAOSwAHZUPMu8

I know it says Vokera but it is what you need, IF your pump head is faulty, I am not so sure it is though

 

[darren6645]

https://www.ebay.co.uk/itm/Vokera-2...456347?hash=item3f3ebc215b:g:hMgAAOSwAHZUPMu8

I know it says Vokera but it is what you need, IF your pump head is faulty, I am not so sure it is though

Me neither I was just going off what I read and seemed easier to stop than the CH pump but it does get more use. I'm not draining and flushing until next week just didn't want to spend a fortune on the inhibitor x4 bottles then find the pumps not upto scratch. Bit of a dilema!

 

[ianmcd]

when you drain it down replace the ballofix pump valves with decent pump gate valves, then if you need to do anything to the pump in the future no need to drain anything

 

[darren6645]

Which valves are best, I've read conflicting reviews, gate valves better, full flow ball valves best. One thing I am wondering is these valves are fitted to allow a pump change without draining system but all posts I've read say they leaked or didn't seat properly when required so drained down and replaced, what's the point?

 

[ianmcd]

pic one for me personally, if a gate valve drips it is an easy fix the other two need replacing

 

[JohnD]

if you wind the gate valve fully open, then close it half a turn, it is less likely to be jammed when you try to use it years from now. A valve that is wound fully open is liable to seize.

 

[darren6645]

pic one for me personally, if a gate valve drips it is an easy fix the other two need replacing

Won't cause me any problems with restricted flow or increased dp with these valves?