Circulation pump replacement.

[JohnD]

A gate valve, open, gives a wider opening than the ball type.

 

[ReJect]

Gate valves are fairly poor at shutting water off fully and can leak at packing nut at spindle.
The quality full flow ball valve type pump valves are good.
Peglers Bulldog pump valves are quality.
Non of the slotted screw type pump valves are any good due to the seal on the screw which leaks badly

 

[darren6645]

Gate valves are fairly poor at shutting water off fully and can leak at packing nut at spindle.
The quality full flow ball valve type pump valves are good.
Peglers Bulldog pump valves are quality.
Non of the slotted screw type pump valves are any good due to the seal on the screw which leaks badly

Do you have a link I can only find these below? What makes them better?

 

[ianmcd]

Do you have a link I can only find these below? What makes them better?

Dont use them they are shoite

 

[ReJect]

Do you have a link I can only find these below? What makes them better?

That is the Pegler pump valves I mentioned. The quality is in the seal that prevents leaks at the spindle. On that type, as far as I aware of, the valve is much the same as a lever operated valve and uses white coloured seal on the ball which is actually a hard type of ptfe.
If you look closely inside that valve or any decent lever valve you will see the white plastic looking seal at edge of the ball.

Cheap valves use rubber seals and they leak when valve is operated or just perish with heat.
The slotted screw pump valves avoid

 

[darren6645]

Dont use them they are shoite

This is why I asked.
I was getting gate valves then read a thread with the information below on those valves so got confused.
I still think gate valves are the way forward, as long as they are operated 6 monthly and not wound wide open to a stop they should last and if they leak from the spindle it can be repacked with ptfe, like a radiator valve

 

[ReJect]

This is why I asked.
I was getting gate valves then read a thread with the information below on those valves so got confused.
I still think gate valves are the way forward, as long as they are operated 6 monthly and not wound wide open to a stop they should last and if they leak from the spindle it can be repacked with ptfe, like a radiator valve

Don't get me wrong about pump valves, - I still install gate valve types. They give reasonable service and I manage to shut them off fairly well in most times I have to replace a pump. But they are poor and subject to corrosion inside or crud preventing them closing fully. It is only a brass gate closing down to a flat brass face inside the valve, so gate valves are a crude valve, more designed for working on hot water systems, like heating.
A quality lever valve has fully tight shut off and no leaks at spindle and that is why they are also available as gas valves.
Lever valves are the way to go and the preferred valve of choice for professionals nowadays

 

[darren6645]

Don't get me wrong about pump valves, - I still install gate valve types. They give reasonable service and I manage to shut them off fairly well in most times I have to replace a pump. But they are poor and subject to corrosion inside or crud preventing them closing fully. It is only a brass gate closing down to a flat brass face inside the valve, so gate valves are a crude valve, more designed for working on hot water systems, like heating.
A quality lever valve has fully tight shut off and no leaks at spindle and that is why they are also available as gas valves.
Lever valves are the way to go and the preferred valve of choice for professionals nowadays

Thanks for that. I would be fitting them on my hot water ch system, either side of my thermal store circulation pump and my ch circulation pump.

 

[darren6645]

I'm going to be tackling this job on Friday. System will have had sentinel x400 in for 2 weeks by then. Draining down, refilling and flushing x4 before filling and dosing. Still uncertain if thermal store circulation pump is partly to blame for the noise when boiler on max heat, having removed bleed screw, pump spins freely with screwdriver but can be stopped on its max setting 3 with small amount of force by inserting screwdriver and on setting 2 can be stopped very easily,not sure how much force is needed to confirm it's slowing down?
While the system is drained I'll remove the pump head and investigate further to see if there's any signs of the pump at fault. I will also attempt to open and close the isolation valves either side of the pump, then see how they hold when I'm flushing the system. If they hold and don't leak then great, if they do leak or are sized I'll replace them in case the pump needs changing at a later date.
What are verdicts on pumps? Was considering just changing the head but the prices appear to be not much different for a new more energy efficient pump.
1st image is my pump which I may be changing. What are views on the other pumps as possible replacements as a more efficient quality pump?

 

[ianmcd]

If they hold and don't leak then great,

replace them, even if they dont leak , when you need them in the future and they do leak you will look like a total twot just do it you know it makes sense , they are not expensive

 

[darren6645]

replace them, even if they dont leak , when you need them in the future and they do leak you will look like a total twot just do it you know it makes sense , they are not expensive

Any advice on pumps?
As you know mine circulates the thermal store constantly so quiet and efficient is good, some of these have modulation or auto settings but as its only circulating the tank not sure they will be any advantage to me, probably just need constant speed setting, on that pump anyway.
I appreciate a head change is easier but if I'm changing valves I may as well change complete pump if required as I'm struggling to source just a head and those I have seen are more expensive than the full pump.

 

[ReJect]

You only need a constant flow pump with low head, as no restrictions because it is just open flow into store

 

[darren6645]

You only need a constant flow pump with low head, as no restrictions because it is just open flow into store

So any of the above will do? They do have other features but I wouldn't need them just constant flow which is one of the settings. There's a bit of difference in price so I'm looking for advice on which are best wilo, grundfos etc. I can't find a replacement head for my existing pump so may have to change full pump.
I've downloaded the Grundfos app, entered my pump details and it's coming up with the ups3 as replacement but then says we recommend only changing the head, which grundfos no longer stock? So looking for alternatives or better pump.

 

[ReJect]

So any of the above will do? They do have other features but I wouldn't need them just constant flow which is one of the settings. There's a bit of difference in price so I'm looking for advice on which are best wilo, grundfos etc. I can't find a replacement head for my existing pump so may have to change full pump.
I've downloaded the Grundfos app, entered my pump details and it's coming up with the ups3 as replacement but then says we recommend only changing the head, which grundfos no longer stock? So looking for alternatives or better pump.

I would think even just a 5m pump will be more than good enough.
If you do buy a A rated pump, you could set the pump at a fixed power as they have the option of fixed settings as well as variable. It will never need to variable as nothing else on that circuit

 

[darren6645]

Just thought I'd update and say thanks to all who helped.
Drained system after circulating x400 for 2 weeks. Filled, circulated and drained another 4 times. Removed 4 seized ball valves and replaced with gate valves. Removed head from grundfos British gas multi head pump for inspection but impeller and shaft stayed attached to pump body, separating from the heat? Couldn't pull it apart, impeller would turn by hand but didn't spin freely on its own. Put the head back on and the impeller could be rattled back and forward in the body. Decided to fit new pump as couldn't inspect impeller etc properly and time was getting on. System filled, all rads bled and system dosed with 2l of inhibitor. System has been almost silent since starting up and the new pump I fitted is currently circulating the thermal store on speed setting 1,other pump needed to be on 3 to reduce noise to minimum. So far so good hope its now sorted for good.