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Hi everyone

Cross-posted this from the commercial section, as it looks like nobody has commented on anything over there since mid January.


I have a dead pump on my DHW

This monster pushes water around the heating coil of s 210 litre unvented cylinder. That's all

It used to be 2 cylinders, and will be again at some point (I have questions about that too but I'll create a new thread)

My question is - does anyone know if this pump can be rebuilt? If not - can anyone suggest a replacement? Best I can do so far costs over £1000, which is bonkers when I know a domestic circulator would do the job - problem is I can't fit one to 2.5 inch iron pipe and 3 phase supply.

Suggestions anyone?

I did ask over on the electrician forum about changing the supply to single phase - that's not simple either.
IMG_20190322_145552.jpg


IMG_20190322_145643.jpg
 
Looks pretty ancient!
Have you contacted the manufacturer?
 
Manufacturer is Pioneer who don't seem to have a presence on Europe any longer - if they even exist . No luck googling the model number either.

Anything that physically fits would do - it's stupidly over-sized. Then again, it lasted 40 years!
 
i presume you are either in a large house or own a care home,

1) does the pump need to be 3 phase this increases the price.
2) it is possible to replace i would guess you could get pump for less than £1000.
3) contact one of the pump suppliers they will be able to advise your best replacement,
4) to fit a smaller non domestic sized pump thyy use unions instead of flanged is feasible but there would be some jiggery pokery with pipework and fittings to make it fit.
5) try a local pump service they can tell you if it can be repaired. but looking at it i would say it can't

i have lived in manchester and worked around altrincham (broad heath) all my life and never heard of the supplier.
 
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Looks the the pipe work could be easily unscrewed at the reducers and adapted to fit another pump
 
i presume you are either in a large house or own a care home,

1) does the pump need to be 3 phase this increases the price.
2) it is possible to replace i would guess you could get pump for less than £1000.
3) contact one of the pump suppliers they will be able to advise your best replacement,
4) to fit a smaller non domestic sized pump thyy use unions instead of flanged is feasible but there would be some jiggery pokery with pipework and fittings to make it fit.
5) try a local pump service they can tell you if it can be repaired. but looking at it i would say it can't

i have lived in manchester and worked around altrincham (broad heath) all my life and never heard of the supplier.

Both. It's a house now, however years ago it was a care home :)

Needs to be 3 phase as it's supply is 3 wire no neutral, fed from a contactor with overcurrent protection. If I use a transformer across phases to get 240 single phase it will mess with the protection device (more precisely the current on one phase will be out of range and cause it to trip)


Option 4 would be good except for the above.
 
Hello,
We spoke on the other side.

If all this does is a DHW Cylinder coil, the best solution would be to reduce the pipe size to the correct size for the coil,
(and future/additional coil) and use a correctly sized pump on single phase. There must be a neutral for the single phase side to the Boiler controls in the control panel?
You could use the existing pipework and a domestic pump but it will take longer to heat the cylinder, it's not something I would do personally although it will work.
What is the Heating system circulated by?
What Boiler/Boilers do you have?
Is there a Header of any kind?
 
Hi

If I run a completely new supply to a new pump, then single phase is easy - there's a neutral available in the panel, it's just using the existing controls/contactor/pyro cabling for the dead pump is a lot easier than re-doing all of that.

The heating (2 zones) is circulated by 2 pairs (primary and backup) of the same type of pumping. Picture attached of the working backup DHW pump data plate.

Boilers are 2 X Clyde Combustion 220000 BTU. Combined output about 130 KW.

They feed a header from which all 3 zones are taken.

IMG_20190324_192342.jpg
 
I think you're going to have to make alterations or stand the cost of replacing the pump for its equivalent.

I wouldn't think you will find anyone to repair that kind of motor. The only motors I generally have repaired are on glanded pumps and that is a different kettle of fish. Lately the motors have been cheaper to replace rather than rewinding.

Is there a reason why can you not take LNE in the panel to the contactor instead of L1 L2 L3 and use the existing as LNE to a single phase pump? Or is the picture in my head different to what's there?
It's difficult when you're not stood in front of something.
 
........
Is there a reason why can you not take LNE in the panel to the contactor instead of L1 L2 L3 and use the existing as LNE to a single phase pump? Or is the picture in my head different to what's there?
It's difficult when you're not stood in front of something.

I can - but I'll have to dis L2 and L3, use one of the freed up poles for the neutral and loop L1 through the other pole, otherwise the overcurrent relay will trip. I assume you're not suggesting I switch the earth? That's already connected through the MICC sheath anyway. The attached pic shows why I don't really want to mess with it :)
IMG_20190326_202438.jpg
 
To convert to SP, the overload will be no use anyway as it will be the wrong type. Simplist way is to re-wire the panel for that pump, find the relevant breaker for that pump, re-size breaker for single phase pump and remove overload, use the freed up l2 and l3 to switch neutral.
So:
1. Locate contactor/overload and breaker / fuse for that pump.
2. Remove L2 and L3 looped wires for that contactor or if fed from own breaker, remove breaker and wires.
3. Run neutral to vacant L2 position on contactor
4. Remove L3 wire from overload to terminal block
5. Remove overload.
6. Re-position wires from overload to contactor.
7. Install SP breaker correctly sized for SP motor
8. Install L1 wire through breaker to contactor L1
9. Re-task wires at terminal box for pump for L1 and N

I may have missed something as i cannot see the detail in the board but you get the gist.
You just need a SP breaker circa C curve 6 amps and a bit of wire, takes about 1/2 hour.
Hope this helps
 
Tvm for that it was the overload relay that I was worried about. The one in question is too heavy - minimum adjustment is 0.9a which is too much to be useful.

Are you saying forget about having overload disconnect on the contactor and rely on the new 6a breaker for overload protection? I guess that's similar to what domestic installs have anyway.
 
exactly, you can get B, C and D curve breakers which will more than deal with a poorly pump, remember you dont have the issue of missing phases with SP as there is only one, the pump either runs or it trips the breaker, no single or two phasing issues you can get with TP motors.
 
Right. Of course I should have thought of that. I was wondering what the point of the overload relay was, given that there is as 6a 3 pole breaker too. Didn't consider the lose-a-phase scenario.

That's the difference between domestic and commercial experience. Of course I know about single phasing, it just didn't occur to me.

Cheers !
 

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