Help on a corroded hot water pump please

[Stew202]

Hi All,
My hot water electrics kept tripping out and i have now identified its the electrics in the hot water pump shown in the picture that is the problem.
Looking at the amount of corrosion I assume water has penetrated the pump and causes the short. I will order a new one. A couple of questions:
1) The pump says its a UPS 15-50 "B" 130 but i can only find an "N" 130 for sale - what is the difference between the B and N ?

2) do you think the corrosion on the out flow nut and isolator will clean up ok and if so how - or do you think that needs replacing too?

I will attempt to do the pump change myself so if there is anything you would advise in the process apart from closing the isolators before the work, would be great.

Thanks in advance!
Stew202

 

[Madrab]

The B denoted Bronze (colour of the plate) and the N denotes Stainless Steel .... the N (Stainless Steel) is now used for the HW circulator.

You're going to have fun getting that pump nut off, soak a cloth in neat limescale remover and wrap it around that fitting, adding more every now and then to try and get some into that.

 

[JohnD]

I think it is mostly limescale rather than corrosion. Some of it will come off with a BRASS wire brush.

You will need good quality, large spanners of the correct size.

It is difficult getting chemicals into plumbing fittings because they are deliberately made waterproof.

It is possible to drill a small hole down the thread if you'll never need to use it again.

The isolators are probably seized and will break, but you can probably close them (once)

Buy new ones and assume a drain down.

 

[Stew202]

The B denoted Bronze (colour of the plate) and the N denotes Stainless Steel .... the N (Stainless Steel) is now used for the HW circulator.

You're going to have fun getting that pump nut off, soak a cloth in neat limescale remover and wrap it around that fitting, adding more every now and then to try and get some into that.

- Thanks Rob - i will give that a go

 

[Stew202]

I think it is mostly limescale rather than corrosion. Some of it will come off with a BRASS wire brush.

You will need good quality, large spanners of the correct size.

It is difficult getting chemicals into plumbing fittings because they are deliberately made waterproof.

It is possible to drill a small hole down the thread if you'll never need to use it again.

The isolators are probably seized and will break, but you can probably close them (once)

Buy new ones and assume a drain down.

- Thanks for the swift reply JohnD - it may be a job for the plumber then , rather than me make a mess of it..

 

[Mottie]

A plumber customer of mine says he normally cuts through those nuts with a junior hacksaw and fits new ones. The do slip back on easily as they have a cut out in them.

 

[oilhead]

You will be able to swap just the head and use the standard head. Apart from the colour of the paint, there is no difference in the heads between hot water and heating circulators.