Plumbers please! MP53 Circulating pump woes

[Beanwood]

Help - I have no hot water!

I have an oil boiler that feeds a thermal store - and I THINK this pump feeds the thermall store (It's a maze of pipes!)

Anyway - the pump is making a racket, and is very hot - so I'm thinking something like bearings have gone.

Is it repairable, or do I just replace.

If I replace it, is there something that wil fit directly, as MP53 doesn't appear to be current anymore.

Is it a straight forward job to replace the pump ? There look to be isolating valves either side - so that should be OK. I don't really want to do any pipe work - (My brother is the plumber - but is typically IMPOSSIBLE to get hold of!!)

Thanks all.

 

[hermetic]

first loosen the black plastic plug in the end of the pump to see if there is air in the pump, you should get a trickle or rusty water. If it is still noisy, turn both valves off (clockwise) and remove the four allen screws and pull the pump away from the body. Check that the hollow impellor is clear of debris and sludge, and rotate the pump by hand and check for lateral play. the bearings are water lubricated so if there is air in the pump they may be damaged, but this is unusual. Reassemble and test, but remember to loosen the black cap to bleed the air out! if it is still noisy it will need a new pump, not hard to change, getting the robber washers between the valve and pump seated correctly can be fiddly if the pipework is tight, but usually a job of about 30 minutes to one hour! You may be able to ask your bro if the CP53 motor unit will fit the MP53 body I have often just changed the motor unit and found that this can be done even across different brands of pumps!! same company making all the pump castings? who knows? Git er done!
Phil

 

[Beanwood]

first loosen the black plastic plug in the end of the pump to see if there is air in the pump, you should get a trickle or rusty water. If it is still noisy, turn both valves off (clockwise) and remove the four allen screws and pull the pump away from the body. Check that the hollow impellor is clear of debris and sludge, and rotate the pump by hand and check for lateral play. the bearings are water lubricated so if there is air in the pump they may be damaged, but this is unusual. Reassemble and test, but remember to loosen the black cap to bleed the air out! if it is still noisy it will need a new pump, not hard to change, getting the robber washers between the valve and pump seated correctly can be fiddly if the pipework is tight, but usually a job of about 30 minutes to one hour! You may be able to ask your bro if the CP53 motor unit will fit the MP53 body I have often just changed the motor unit and found that this can be done even across different brands of pumps!! same company making all the pump castings? who knows? Git er done!
Phil

Failed at the first hurdle - open the black cap, and nothing comes out at all?
Could that mean I'm out of water somehow?

 

[Blobber]

The gate valves either side dont always shut off so be careful, if its a vented system your cold feed from the small header tank could be blocked which is a common problem

 

[Nomad]

Above have more experience than me, but as someone who has fitted/refitted a few of these pumps I'd expect -
Remove the black cap, water should drip out
You can then see the end of the motor shaft, some have a slot you can put a screwdriver in - turn the shaft to check it's not siezed.
For a quick final test I then leave the cap off and briefly turn on the heating, you should see then end of the shaft turn, refit the cap as soon as you see it's working,

As you're not seeing any water I can only guess the system is dry (not sure how this is possible - that's a lot of water gone somewhere) or there's a blockage somewhere

 

[Beanwood]

The gate valves either side dont always shut off so be careful, if its a vented system your cold feed from the small header tank could be blocked which is a common problem

I think it's a sealed system - thermal store - with a vent in the loft to big bucket thing.

 

[Beanwood]

Above have more experience than me, but as someone who has fitted/refitted a few of these pumps I'd expect -
Remove the black cap, water should drip out
You can then see the end of the motor shaft, some have a slot you can put a screwdriver in - turn the shaft to check it's not siezed.
For a quick final test I then leave the cap off and briefly turn on the heating, you should see then end of the shaft turn, refit the cap as soon as you see it's working,

As you're not seeing any water I can only guess the system is dry (not sure how this is possible - that's a lot of water gone somewhere) or there's a blockage somewhere

Cap won't remove completely - It's held in by a spring by the feel of it - and I don't want to force it just incase it won't then re-seal

 

[gaz1]

theres more involved than that that just a quick way shut down and trace your pipes your looking for selonoid valves

and anything that controls water or blocks it pumps, valves or even a failed boiler thats leaking can block silly pipes off corrosion of the system its all factors

dont just blame it on a pump yes it can be but you owners never consider maintenance of your heating systems until you need it or something goes wrong

 

[gaz1]

Cap won't remove completely - It's held in by a spring by the feel of it - and I don't want to force it just incase it won't then re-seal

cap will come off if it has a spring inside just push a flat blade between the spring and down the stem you need to feel a spin

 

[Beanwood]

theres more involved than that that just a quick way shut down and trace your pipes your looking for selonoid valves

and anything that controls water or blocks it pumps, valves or even a failed boiler thats leaking can block silly pipes off corrosion of the system its all factors

dont just blame it on a pump yes it can be but you owners never consider maintenance of your heating systems until you need it or something goes wrong

I'm aboslutely certain there's more to it that I understand currenly - but not quite sure I get what you mean - it's the pump which is hot and noisy - so that's where I'm starting.

Boiler was serviced last year - I'm not sure what else I should be getting serviced?

 

[minimutly]

Helpful as usual @gaz1 ...
To be fair you did tell him how to remove the cap.
If you need to change the pump you will need a set of - water pump pliers!
I would slacken the top one off to check you have water in the system - should come spurting out because the pump has flat sealing faces top and bottom.
I once had a low hours grundfoss shear it’s shaft, could never work out why?

 

[Matrixx]

The bearings are just bushes basically , it needs water to lubricate , and cool, is it running dry?

 

[Beanwood]

The bearings are just bushes basically , it needs water to lubricate , and cool, is it running dry?

It might be

 

[Matrixx]

Switch off the supply , closed the valves either side, remove the 4 Allen screws , if no water just crack open one of the valves to see if water comes out.
The pipes should be hot if the pump is hot. ?

 

[Beanwood]

Progress!!

It seems that I was short on water, so the pump was just running dry - there is a small header tank in the loft, and the ball valve was stuck shut.
I have opened it to allow some water in - and that has resolved the noise - and I have hot water again.
So I just need to replace a ball valve - which is a much better option.

 

[gaz1]

told ya so always check other things first than go in all diving first and blaming other things

 

[Pigeon_Droppings2]

So I just need to replace a ball valve - which is a much better option.

Or just do what the previous owner of my house did....just leave it and top it up once a month

As the house keys were handed over it was one of the instructions he gave me...why would anyone want to be dragging a bucket of water into the loft every month!

 

[DanZac]

It seems that I was short on water, so the pump was just running dry - there is a small header tank in the loft, and the ball valve was stuck shut.
I have opened it to allow some water in - and that has resolved the noise - and I have hot water again.

Where's the water that was in the tank gone?

Im not a plumber but isn't the tank just to make up for any expansion or system losses. Which means if the tanks empty and the pumps running dry, the system is losing water somewhere (I.e you've got a leak)?

 

[Pigeon_Droppings2]

Im not a plumber but isn't the tank just to make up for any expansion or system losses. Which means if the tanks empty and the pumps running dry, the system is losing water somewhere

I think it just evaporates over time....so it will have gone dry over a long period of time....hence the built in top up tank.

 

[Beanwood]

Where's the water that was in the tank gone?

Im not a plumber but isn't the tank just to make up for any expansion or system losses. Which means if the tanks empty and the pumps running dry, the system is losing water somewhere (I.e you've got a leak)?

Fair question - but as it's a very small tank in a very hot loft, (It's only about 5 litres total), I had imagined it's evaporated over the past 11 years. I topped it up with probably less than 2 litres - so not very much at all ?