Non-motoring > Changing tap washers... Miscellaneous
Thread Author: Ambo Replies: 41

 Changing tap washers... - Ambo
...without draining the system. Our 1930s house has a spare bedroom, with a washbasin connected to the hot water tank via lead pipes. Its washers need changing as I fear they will leak before long. A plumber tells me that a pipe-freezer cannot be used on lead.

I am reluctant to drain the whole system, with subsequent bleeding of my 17 radiators (which have copper connections, being no doubt a later addition) and perhaps other complications I can't foresee. If I did, I could replace the pipes with copper ones but that would involve a major upheaval.

Can anyone suggest an alternative to abandoning use of the basin please?
 Changing tap washers... - Bromptonaut
Are you sure that draining the hot water system involves the heating?

Ours has a big header tank for the hot water (and some upstairs taps) and a smaller one for the rads and the indirect water heating.

Last time we had taps replaced the heating stayed on. Plumber had a hell of a game with airlocks in the H/W system though.
 Changing tap washers... - Ambo
>>Are you sure that draining the hot water system involves the heating?

No, a point to check.
 Changing tap washers... - bathtub tom
Have you still got a 'primatic' or 'semi primatic' system, where your hot water and heating share the same water, or do you have a separate tank in the loft that feeds just the heating?

My '60s built house used to have a 'semi primatic' system that I dispensed with decades ago, because it meant I couldn't add corrosion inhibitor or anything else and the boiler was 'kettling' due to a hard water supply.

My hot water cylinder has a cold water feed with an isolating valve. Turning that off stops the hot water cylinder from filling and it's just a case of turning on the hot taps to drain what's in the pipes and off you go.
Last edited by: bathtub tom on Tue 15 Dec 20 at 10:29
 Changing tap washers... - Ambo
>>Have you still got a 'primatic' or 'semi primatic' system, where your hot water and heating share the same water, or do you have a separate tank in the loft that feeds just the heating?

I don't know what these terms mean but here is no separate tank. However, the hot water and heating can act independently so the hot water can be shut off and leave the heating on, and vice versa. I believe this is called a "dual system".
 Changing tap washers... - Falkirk Bairn
Our hot water pressure is not that great.

Lots of towels etc on floor.
I bought a tap renovator pack - £8.00 IIRC at Toolstation.
Unscrewed the innards, dropped it and immediately screwed the new tap innards.

Not a lot of water spilt - worked for me.

PS I had practised on the downstairs tap that was easily shut off!
 Changing tap washers... - Duncan
>> ...without draining the system. Our 1930s house has a spare bedroom, with a washbasin connected
>> to the hot water tank via lead pipes. Its washers need changing as I fear
>> they will leak before long. A plumber tells me that a pipe-freezer cannot be used
>> on lead.

Remedy

If you can't/don't want to turn the system off. Normally you won't be affecting the central heating system as it will be on a different circuit. Most unusual not to be.

Get everything ready. What are you doing first? Hot tap, or cold tap? Turn on other taps, hot or cold as the case may be, let them run, having made sure that the plugs are not in.

Turn your tap on. Whip the stem of the tap off on the basin you are doing, there shouldn't be much water come out as all the other taps on the circuit are running. Quickly change the washer, replace the tap stem, turn the tap off. Turn other taps off that you turned on. Job jobbed. Repeat for the other tap, if necessary.

Note. Have a good rummage under the kitchen sink and in the airing cupboard, I would be surprised if you didn't find a valve that would turn off the hot/cold to the basin (it was a basin, wasn't it?) that you wish to work on.

I hope that all makes sense. You've got my number, haven't you?
 Changing tap washers... - Fullchat
Is it all going to come apart easily for you just to change the washer in quick time?

I saw a video clip the other day of a plumber stuffing a piece of white bread (it has to be white ) in 15mm copper pipe to hold back remaining water in the pipe so he could solder a joint. You cannot solder with any water in a pipe. The bread dissolves sufficiently for it not to cause blockages.

Turning on all the other taps to reduce flow sounds a good idea.

Do you have a plan B if things start to go wrong?
Last edited by: Fullchat on Tue 15 Dec 20 at 11:40
 Changing tap washers... - sherlock47
But make sure you have a plan B for when the thread strips in taking out the insert.
 Changing tap washers... - No FM2R
Turn off the water to the house and simply change the tap washer. Drain nothing. It won't leak much.
 Changing tap washers... - Zero
If its not leaking now, its not going to if left unused. Mothball it because of the lead pipes.
 Changing tap washers... - Ambo
Why "because of the lead pipes"?
 Changing tap washers... - Zero
Because they dissolve and leach lead into the water
 Changing tap washers... - No FM2R
Yes, not good. You certainly should not drink it. Nor use it in cooking, though since it is in a bedroom I guess that doesn't apply.

I'd recommend either replacing the pipes or simply removing the basin and existing pipes.
 Changing tap washers... - Kevin
Another vote for ripping it out.
It's a waste of space and you can only use it for P'ing in because of the lead piping.
 Changing tap washers... - Dave_
There's no need to rush. There will always be an easy way of turning off the water to the taps in the basin.

All you have to do to check you've turned the correct water off is to try running the taps for a few minutes and see if the flow slows and stops.

Cold tap: if there is a header tank in the loft (possible on a 1930s system), there will be a gate valve of some sort on the pipe coming out of the bottom of the tank. If the cold taps are all connected directly to the water main then turning off the stopcock for the house supply will do what you need it to.

Hot tap: Again, there will be a gate valve on the large pipe going into the hot water cylinder. Just turn it off and run the hot tap(s) to see if the flow slows and stops.

All taps and valves always turn clockwise to shut off the flow, and anticlockwise to turn the flow on again.

A little tip for stopcocks and gate valves: Don't leave them fully closed or fully open - when it won't turn any more, back off 1/4 of a turn. This can help to prevent the mechanism seizing when you want to use it the next time.
 Changing tap washers... - CGNorwich
If there is a header tank in the loft for cold and the gate valve is stuck (a common occurence on old systems) tie off the ball valve so no more water can enter the tank and the tank will eventually drain from the tank when you turn on the basin tap. To tie off the valve put a bit of wood across the tank and secure the ball valve to it with a bit of string
 Changing tap washers... - Bromptonaut
>> If there is a header tank in the loft for cold and the gate valve
>> is stuck (a common occurence on old systems) tie off the ball valve so no
>> more water can enter the tank and the tank will eventually drain from the tank
>> when you turn on the basin tap. To tie off the valve put a bit
>> of wood across the tank and secure the ball valve to it with a bit
>> of string

That's what plumbers do here - no gate valve at all. Stops the water but refilling is a s o d of a job as the monkeys to whom the builder subbed the plumbing made it susceptible to multiple airlocks.
 Changing tap washers... - Robin O'Reliant
Over time I've fitted isolating valves to the pipes just below the taps throughout the house. It makes these sort of jobs trouble free.
 Changing tap washers... - Zero
>> Over time I've fitted isolating valves to the pipes just below the taps throughout the
>> house. It makes these sort of jobs trouble free.

And here too, but have you tried working with lead pipes?
 Changing tap washers... - Robin O'Reliant
>>
>>
>> And here too, but have you tried working with lead pipes?
>>
Not stuck with them, thank God.
 Changing tap washers... - No FM2R
>>have you tried working with lead pipes?

Rip 'em out and sell them for scrap. About all they're good for.
 Changing tap washers... - martin aston
Robin yes I have isolating valves too. However they are themselves prone to fail. One of mine went last Boxing Day and I had to experiment with the screw setting to get the drip to the lowest possible level and stick a bucket under it until Screwfix reopened.

Two very good plumbers have since told me that they are frequent leak sources. Even good quality ones.
 Changing tap washers... - bathtub tom
I've had one of them leak in the loft. Discovered when water started dripping out of a bedroom light.
 Changing tap washers... - henry k
I have not had any failures with isolatimg valves.
If flow rates are important beware of cheap fittings.
The cheap 15mm ones fitted in my daughters flat had a bore of about 10mm.
Easy to note the true bore.
 Changing tap washers... - CGNorwich
“Easy to note the true bore.”

Indeed. :-)
 Changing tap washers... - Ambo
Most of my other taps and my two toilet cisterns have service taps and there have been no leaks so far. However, various forms of disability keep me out of the roof space and I will have to get a plumber in to sort matters out. Many thanks for all suggestions; they will help me in dealing with him.


 Changing tap washers... - Bromptonaut
>> I have not had any failures with isolating valves.

Not here either. The developers employed a team of Monkeys to do our plumbing and it's hit/miss whether things are protected by isolating valves but I was very glad the en suite loo had one when its float valve tail sprang a leak in the summer.
 Changing tap washers... - Dave_
>> it's hit/miss whether things are protected by isolating valves

It shouldn't have been signed off by Building Control if they weren't.
 Changing tap washers... - bathtub tom
>> >> it's hit/miss whether things are protected by isolating valves
> It shouldn't have been signed off by Building Control if they weren't.

Were building control around in the days of lead pipes?
 Changing tap washers... - hawkeye
>>
>> A little tip for stopcocks and gate valves: Don't leave them fully closed or fully
>> open - when it won't turn any more, back off 1/4 of a turn. This
>> can help to prevent the mechanism seizing when you want to use it the next
>> time.
>>

Spot on. Also it doesn't hurt to 'exercise' the valve when you are passing. Close a complete turn and open again. This helped earlier this year when I had to replace a 19-year-old CH pump head at the holiday home being observed by guests making pithy comments to me (and filming the process) between slurps of beer. .
 Changing tap washers... - Ambo
Interesting. My Potterton Kingfisher 2 RS 80 boiler was installed 23 years ago. The plumber told me this type is very simple with not much to go wrong, but three years ago he advised me to buy a replacement pump as this would be the most likely source of failure and spares were getting hard to find. This I did but he is no longer available to consult, although there is no trouble at present, so could you say if you had to drain your system before changing your own pump?
 Changing tap washers... - Duncan
There should be isolating valves each side of the pump. Changing a pump is a fairly simple matter. Turn the system off before starting work. If you have isolating valves, you shouldn't have to drain down.
 Changing tap washers... - Zero
>> There should be isolating valves each side of the pump. Changing a pump is a
>> fairly simple matter. Turn the system off before starting work. If you have isolating valves,
>> you shouldn't have to drain down.

Only if you have previously copaslipped the large pump nuts. If you haven't they aint coming off and you are drainign down the system to put new ones on
 Changing tap washers... - hawkeye
>> Only if you have previously copaslipped the large pump nuts. If you haven't they aint
>> coming off and you are drainign down the system to put new ones on
>>

Change just the pump head if you can; the large nuts can be devils to move. I have 2 Grundfos pumps and a spare pump head so only 4 x 6mm female hex bolts to remove. Grundfos pumps are all the same fitting I believe.
 Changing tap washers... - Zero

>> Change just the pump head if you can; the large nuts can be devils to
>> move. I have 2 Grundfos pumps and a spare pump head so only 4 x
>> 6mm female hex bolts to remove. Grundfos pumps are all the same fitting I believe.

Ooo - Thats an interesting concept, just had a look, and yes you can get grundfos pump heads.

So why would one not buy a pump head every time? what's left in the pump body and what's in the pump head?
 Changing tap washers... - tyrednemotional
>>
>> So why would one not buy a pump head every time? what's left in the
>> pump body and what's in the pump head?
>>

I think this is the equivalent to the repair I carried out on my 3-port valve. (i.e. leave the casting alone and replace all the "innards")

Essentially, the pump body is simply a casting, containing nothing but air (or water ;-) ), and to which all the rest of the pump (impeller, motor, control box) bolts.

It is entirely possible, therefore, to replace all parts that might fail/wear without having to undo pipework and remove the body.

Of course, the ease of doing so will depend on how securely the pump head is fastened to the body, but it is likely that this will suffer considerably less from seizing than the body/pipework connections.

My pump, fitted some time ago by myself is also a Grundfos. I'm not sure that you can get a replacement head (only) for that model, but it would seem entirely possible, and perhaps sensible, to buy a full unit and cannibalise, not least since the installation process allows for various positioning of the pump head (4 x 90 degree options) which involves removing the head from the body (4 hex bolts as above) and retightening after the desired position is achieved.
 Changing tap washers... - Zero

>> Essentially, the pump body is simply a casting, containing nothing but air (or water ;-)
>> ), and to which all the rest of the pump (impeller, motor, control box) bolts.

I've just had a scan round Youtube. Little mention of pump heads being replaced, tho there was one. I kind of assumed there would be a bearing or some such in the pump body, but no it seems the motor is fully contained in a cartridge attached to the pump head. So yes, the pump body is just a chamber with the in and out ports.
 Changing tap washers... - hawkeye
>> So why would one not buy a pump head every time?

Well you can on Ebay ...

Possibly because there's no standard of connecting the head to the body across manufacturers. Ebay will sell you some Grundfos-style cheap tat. The Grundfos pumps with the 4 bolts are in the holiday rental but my 'caretaker's residence' has an air source heat pump and 4 Lowara Ecocirc pumps to push water around. Totally different; the Lowaras need a big hook wrench to loosen the chunky collar which holds the head on. The magnetic impeller allegedly 'floats' on a cushion of water in the pump body with no conventional bearings visible.

My first pump head removal was out of necessity; I'd left my big Stillsons at home when I went to a 'hot water OK, no central heating' call. I was all set to beetle off to the plumbers' merchants after finding the boiler working well until it shut down on overheat, and the pump dead. Or was it? It was stalled but humming at me. Off came the head to reveal some disgusting organic matter and grit gumming up the impeller. May have been an infant mouse.

Reassemby? take the big O-ring off and heat it up in some near-boiling water in case it's out of shape. Reassemble with a smear of silicone grease on the mating surfaces and you're entitled to a cuppa and a ginger biscuit unless you're in a country where these are difficult to come by.

Oh, and don't think you can test your handiwork by running the pump with the impeller dipped in a bowl of water; you and the surroundings are likely to get drenched. They are hostile little so-and-sos.


Last edited by: hawkeye on Sun 3 Jan 21 at 17:27
 Changing tap washers... - Zero
>> Interesting. My Potterton Kingfisher 2 RS 80 boiler was installed 23 years ago. The plumber
>> told me this type is very simple with not much to go wrong,

The Heat exchanger will eventually warp, split the sealing cement between the two sides and it will leak over your burners. Around the 25-30 years mark
Last edited by: Zero on Sat 2 Jan 21 at 12:36
 Changing tap washers... - Ambo
Thanks for the warning. I am constantly amazed at the range and depth of your knowledge, Zero. How did you come across these particular details?
 Changing tap washers... - Zero
My previous boiler, a 27 year old Potterton failed that way. Plumber said, "Yeah that always happens about then"
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