Pump Union Needed?

[3rdWorldClassPlumber]

Hi All,

I've ordered the parts I think I need to replace the existing pump that has failed. I'm referring to the circulator in the airing cupboard. I have a system that has a CWSC and a F&E tank in the loft - also an indirect hot water cylinder.

I've taken delivery (from www.bes.co.uk) today of:

5M HEAD CIRCULATING PUMP, 230V ac, DAB (product no. 13926)
1½" BRASS PUMP NUT ONLY (X 2) (product no. 9347)

I started the 6129 tech. cert. at the local college in September, so I thought I'd tackle the pump replacement.

I think I've omitted to order something, though I'm not quite sure what. I think it's referred to as a union. Looking in the airing cupboard I can see some sort of flange between the nut and the 22mm pipe. Is that the union?

Is the item I need here:

www.bes.co.uk : (product no. 9344 or 9345)

Pictures here?

http://www.tapsandshowers2go.co.uk/index/brass_valves_and_accessories/pump_valves_and_fittings/

I should mention why I haven't bothered with pump isolating valves. Well the existing system is an ancient Glow Worm Space Saver 50 - and the entire lot will be ripped out and replaced after winter. The gate valve above the pump (pump is in a very short run of vertical pipework) has been leaking onto the pump for months. The gate valve, pump, nuts, flanges (unions?) are corroded to hell.

I'm planning on cutting the pipe just before the top of the gate valve and just after the bottom of the flange and remove the entire rotten lot and replace.

I'm using John Reginald Central Heating Fault Finding & Repair as a guide.

Happy Christmas!

3rd WCP

 

[Rob]

for the sake of a tenner why not just use proper pump isolation valves.

 

[3rdWorldClassPlumber]

Hi rob884,

Yup, fair point.

Reason being is that the pump is within a very short run of vertical pipework. There is one (leaking) gate valve above the pump, and just a nut and flange (union?) below the pump. There isn't the room to allow a valve above and below the pump. I don't want to alter the pipework !

I figure if i'm gonna have the whole system replaced soon, and the exisitng gate valve above the pump is leaking and very badly corroded (it'll have to go) and there's no room for a valve below the pump - I may as well omit the valves. Oh well...

I need to know what part/interface/flange/union/component I need to allow the 22mm pipe to enter the pump. The nut and gasket alone are not enough.

Of course, I realise how dumb this question seems to even a lightly seasoned plumber - let alone a well seasoned one.

Cheers.

3RD WCP.

 

[3rdWorldClassPlumber]

Okay, hopefully someone is feeling the season of good will to all men

So, what fitting do I need (in addition to the gasket and nut I already have) to allow 22mm copper pipe to enter a circulating pump?

I've drained down, so hopefully YOU ( ) will post.

Martin.

 

[Gasguru]

I can't find any fitting that will go from 22 compression (or solder) to a pump union. The only fittings are for a screwed connection to pump union.

Installers fit gate pump valves. Cut out the pipework and fit the gate valves.

 

[EliteHeat]

I started the 6129 tech. cert. at the local college in September, so I thought I'd tackle the pump replacement.

Cracking start 3WCP - be sure to mention this little episode to your instructor.

 

[3rdWorldClassPlumber]

Elite!

Oh, yeah - it's rather amusing I must admit.

I've just got back from the last theory lesson at St. Helens College before the Christmas break. Being the last lesson, the instructor didn't talk about cold water (as planned) but we sat about discussing my pump problem (and the general state of plumbing for new entrants).

The instructor has over 30 years plumbing (domestic and commercial) and is highly rated by the staff and students. However - looking through a merchant's catalogue, he couldn't see any fitting that would help. He gave the same advice as GasGuru in the end.

I'm sure there must be some fitting (in my links above?) that I can use so the pipework can enter the pump (and nut and gasket).

I'll hang me head in shame if I ever make it and look back on this post

3rd

 

[ChrisR]

NB - all pump valves are different sizes, so you might be lucky with the pipe lengths, or not!

You can get p[lain unions - in your supplier pic, but they aren't near 22mm copper size, so you'd have to use a 22mm compression to (say)3/4" "iron" (ie bsp) thread, then a bush, up to 1.5 inch.

GIven your original problem, "we " probably wouldn't have bought a new different pump, but noted what the old one was, and got another the same so we could just change the motor - 4 allen screws. Then Bung the f&e, (hope it works), and do it quickly.

 

[3rdWorldClassPlumber]

Hi GasGuru, EliteHeat, ChrisR

Well, I must say there are some extremely knowledgeable and helpful people on here. The least we amateurs can do is tip our hat to the professionals.

I've been reading this forum for a while now, and I recognise your names and know there is a sense of real community amongst the regulars. Even if it does sometimes get a bit "lively".

Another lesson learned for me is that it maybe aint so good to order online until I've got more experience. Fine of you know what you're doing and can order the correct parts straight off. I'd better get friendly with a local merchant (I'm off in 10 mins to find one) and go get the valves. And alter the pipework maybe...

This task will be more interesting than any bending/soldering done so far in the workshop....

3rd

 

[Gasguru]

Could have used the CP 4 speed pump head that fits 5 and 6m Grundfoss and Myson back casings http://www.circulatingpumps.net/products/motorhead.asp

 

[3rdWorldClassPlumber]

Er, let me hold off on the trip to the Merchants for a second.

The existing pump is labelled "circulating pumps" CP63.

Will my DAB VA55/130 head go onto the existing pump (as ChrisR was talking about)? That'd save me a lot of bother. Maybe I can just pack the leaking gate valve (that's just above the pump) with PTFE?

This sounds like an easier fix - if compatibility isn't an issue?

3rd

 

[Gasguru]

Doubt the DAB head will fit. Get another Myson/Circulating pumps 6m head.

Some pumps eg the Wilo run in the opposite direction just to confuse things further.

 

[corgiman]

If you can get it the old servowarm elite 50's used to have just the thing on the pump

But that said I would change the pipework to fit in some isolators as if you do a good job and the punter likes you then it will be you having to change the pump in the future

 

[3rdWorldClassPlumber]

All (i.e. 1stWorldClassPlumbers )

Okay, just got back from Warrington to buy my good lady a cake stand. What's that got to do with plumbing? Er, nowt - I'm just excited that I got her a marvellous cake stand for Christmas and I just know she's been after a quality one for months.

I called in to B&Q on my return just to size the pump valve (i.e. length from end to end). The ball valve is somewhat shorter than the gate valve. I might just get away with having enough room (to fit two ball isolators) without having to alter the pipework.

I seem to remember previous posts recommending the gate valve over the ball valve. Anyways, I'm very glad some familiar (and experienced!) guys replied. How on earth some of you folks manage to spend time on here and earn a crust...? Well, hats off to you all.

A Very Merry Magners Christmas To You All,

3rdWorldClassPlumber