Leaking Pump Gate Valves

[NOVICE66]

I'm a real novice at plumbing and central heating systems but having had some success at diagnosing that the squealing from my central heating pump was caused by a jammed ball valve in the feed system in the loft I've decided to try and tackle (or at least to understand if I think it's beyond me) my next problem.

I have 2 pump gate valves either side of the pump. On both of these there is water leaking out of the small nut which is screwed onto the narrow cylindrical bit that sticks out. The night before last water was pouring out of one of these. I tightened up the nut which alleviated the problem at the time but there is still a small leakage (this is also the case for the other valve which i can't tighten as it seems to be jammed - both valves are heavily scaled).

The obvious answer I'm sure would be to replace both valves but is this an easy job and would this necessitate draining down the system (the pump is in a cupboard upstairs and is higher than any of the radiators)? If so. do I follow the same proceedure as in the text books for a system which has thermostatic radiator valves on it? The system is open vented.

Alternatively, if it is possible that there is a washer between the nut and the valve that has gone, would it be possible to shut off the valves and replace this washer without draining down the system? If this is the case, how do you do this as I can't see any indication of how to turn this valve into the off position?

I'm sure your advice would be to get a plumber in but I am really interested in finding out more about my central heating system and find it really satisfying if I can solve things.

I do have a pic of the valves and pump but can't see any way of uploading it onto this site. If anyone has any tips?

Thanks for your time in advance!!!!!

 

[ollski]

Put your pics on photobucket site or something similar then post the link on here. There are lots of pump valves around some repairable and some not although if I were you I would just drain to below the level of the pump and replace the lot.

 

[gas4you]

For how cheap 2 pump valves are you would be stupid to try and repair them.

Drain down enough to take pump out and replace valves. Use new washers when re-fitting pump. They should come with the valves

 

[NOVICE66]

Thanks for advice.

Valve just looks like the standard 22mm that you would get from Screwfix.

Think the easiest think would be to replace the valves as they are not expensive but does the fact that I have thermostatic rad valves make any difference to draining down the system and how would I know if when it is drained down to the level of the pump?

Thx

 

[nickso]

as ollski says if its the right type of valve you can repair the leak without draining down.

the knack is to close the valve spindle whilst opening up the leaking bit you are talking about....be careful though as you can only open this up about 2-3mm or the whole lot will fall out and then you are screwed. if you do it properly you will get water out but a very small amount. neatly wrap some PTFE around the gap and retighten whilst undoing the spindle.

its not really a job for the novice but if you are brave have a go

 

[gas4you]

Turn off 15mm gate valve for filling system and drain about a bucket of water out of system. If pump is higher as you say then this should be enough. Undo 22mm compression joints on pump valves slowly and have some towels/tissue ready with a bucket just in case.

 

[Rotunda82]

I would agree - replace the pump valves as they are inexpensive. Be careful when draining - the majority of times the 15mm gate valve on the cold feed will be stuck so you may have to turn the water off ( or tie up the ball valve if you have done before and are confident in doing so ). Drain from for a few minutes then as mentioned crack one of the nuts on the pump to see if the water has dropped below this point - It will help if you open any manual air vents that are located near the pump ( if there are any )

Draining is easy - its filling thats fun

 

[nickso]

inexpensive maybe but why replace something for cost when you can repair for free......ok the cost of some PTFE

 

[Soggy_weetabix]

The glands can be repacked in 5 minutes.

The fibre washers on the valves (allbeit with a bit of plumbing knowledge) can be replaced with hemp. That will take 10 minutes. (or Plumbers Tape For Everything.... also known as PTFE.)

Why change the whole lot, as the pump will need wrestling out plus the time to drain down, refill and all the problems that go with it. Pump unions are NEVER easy to undo.

Half an hour of a decent plumbers time will have your problem fixed.

Dave

 

[croydoncorgi]

You'd be well advised NOT to use the fibre washers supplied with new pump valves to replace the RUBBER washers supplied with (eg) Grundfos pumps. Grundfos has it right(er).

 

[nickso]

You'd be well advised NOT to use the fibre washers supplied with new pump valves to replace the RUBBER washers supplied with (eg) Grundfos pumps. Grundfos has it right(er).

agreed, and dont use the rubber washers that come with myson pumps either as they always leak but grundfos dont seem to leak so often......in fact dont use myson pumps as they are rubbish anyway

 

[Agile]

For those who dont know, Myson pumps are now called "Circulating Pumps".

Potterton briefly bought the Myson name and applied it to the pumps which they had bought.

It was losing money and they agreed to a management buyout but without the name.

I went to 2002 one today with a failed cap. It was badged as Icon !

Tony

 

[nickso]

For those who dont know, Myson pumps are now called "Circulating Pumps".

Potterton briefly bought the Myson name and applied it to the pumps which they had bought.

It was losing money and they agreed to a management buyout but without the name.

I went to 2002 one today with a failed cap. It was badged as Icon !

Tony

my mistake.......same ****, different name

 

[gas4you]

my mistake.......same s**t, different name

I was convinced to try myson/circulating pumps by my Plumb Center manager. Out of the four I bought 3 were faulty out of the box!

Cured his piles though