Main Stopcock Replacement

[Tim10]

The handle on the main stopcock where the rising main enters the house in the corner of the kitchen broke off many years ago. We have 2 ways to turn the water off that aren’t ideal. I have filed a square end onto the stopcock spindle where the handle used to fit so this can be turned off with a spanner. This takes a good 5 minutes as it’s in a tight space. Or we can use the stopcock at the boundary of the property, although this involves finding something to prize open the grate, and using a home made key (tube with a notch cut out) to make it easier and quicker to turn. Should we ever have an emergency at 4 in the morning on a cold winter’s morning, we’d be in trouble, so I plan to replace the broken indoor stopcock.

What would be a suitable replacement for use as a main stopcock? Will any bog standard stopcock from a DIY store do, or should it be a certain type? Several types seem to be available, for example at http://www.bes.ltd.uk/nav_graf/frames_cat.htm there is the option of a DZR stopcock, gunmetal stopcock, brass stopcock… Which one of these is the best and most appropriate for the job? The rising main is 15mm copper.

What we have is a stopcock and draincock in one unit. I world rather, unless there’s a specific requirement, fit only a stopcock. We have never once needed to use the draincock in the 31 years we’ve lived here as the entire system can be drained by opening the outside tap, apart from the water in the approx half metre of pipe between the stopcock and first tee. I can’t see any combined stopcock/draincock units available, and I don’t see the point of fitting a separate draincock immediately after the stopcock that we’ll never use because we can already easily drain all the parts of the system that we need to.

Are there any other requirements I’ve missed. A search on the web hasn’t revealed anything.

Thanks

Tim

 

[Softus]

What would be a suitable replacement for use as a main stopcock? Will any bog standard stopcock from a DIY store do, or should it be a certain type?

Bog standard brass with compression fittings, but get the best quality one offered at a plumbers' merchant.

Several types seem to be available, for example at http://www.bes.ltd.uk/nav_graf/frames_cat.htm there is the option of a DZR stopcock, gunmetal stopcock, brass stopcock… Which one of these is the best and most appropriate for the job? The rising main is 15mm copper.[/quote]
Brass stop cock.

I can’t see any combined stopcock/draincock units available, and I don’t see the point of fitting a separate draincock immediately after the stopcock that we’ll never use because we can already easily drain all the parts of the system that we need to.

Nor do I - forget the drain cock.

Are there any other requirements I’ve missed.

Not requirements per se, but consider replacing the valve body of the stop cock if it's a struggle to replace the entire fitting.

Or, consider a popular solution where space is limited - fully open the broken stop cock, turn off at the pavement, fit a brand new stop cock above the old one (i.e. leaving the old one in place), and turn back on again.

 

[Tim10]

Thanks for the reply. OK, a new stand alone brass stopcock it is. That's exactly along the lines as I was thinking, but with so many different sorts available and no clear set of regulations (that I can find) that refer to stopcocks I wasn't sure.

Space is extremely limited, but the kitchen unit that's boxing it all in has to come out when we have the boiler replaced some time over the next few weeks, so it's the ideal opportunity to do it then, when there'll be good access. What I'm going to do is get a short length of new 15mm copper pipe with the inlet of the new stopcock fitted onto one end, and a straight coupling (compression or capilary) fitting on the other, then cut the old pipe just above the old stopcock, and again just below floor level, then fit the new stopcock outlet straight into the pipe cut just above the then removed old stopcock, and then connect the inlet pipe to the rising main as it enters the house below floor level so it looks neater and it'll be easier to make the connection under the house.

The only thing I've not decided on is whether to use a compression or capilary fitting for the connection to the rising main under the house. A compression fitting would be easier and a lot less hassle, but I'd prefer to use a capilary fitting. Two possible problems with using a capilary fitting are if the stopcock in the street doesn't COMPLETELY stop the flow of water, would I need to use a pipe freezing kit to stop the trickle while soldering the joint? And I'm unsure as to whether it's 1/2" pipe, meaning I'd nead a 1/2" to 15mm adapter (?). Is there an easy way to tell whether the existing copper rising main is 1/2" or 15mm? The house was built in 1968?

Tim

 

[Softus]

What I'm going to do is get a short length of new 15mm copper pipe with the inlet of the new stopcock fitted onto one end...

I can see why this might be appealing, but pre-fitting the stopcock onto a section of pipe won't make the job any easier or quicker, and might make it harder.

The only thing I've not decided on is whether to use a compression or capilary fitting for the connection to the rising main under the house. A compression fitting would be easier and a lot less hassle, but I'd prefer to use a capilary fitting.

Perfectly understandable. However, be VERY careful if you cut the old copper - being nearly 40 years old it could easily be thinned and worn and thus liable to folding/puckering/cracking.

Two possible problems with using a capilary fitting are if the stopcock in the street doesn't COMPLETELY stop the flow of water, would I need to use a pipe freezing kit to stop the trickle while soldering the joint?

Yes, and you'd need to suck the remaining water out of the pipe or the solder won't flow. Also, the old pipe will be dirty, so you'll need to thoroughly clean the surface to have any chance of a good enough solder joint. And you'd need to do all of that with the pressure of having a limited time before the pipe thaws.

And I'm unsure as to whether it's 1/2" pipe, meaning I'd nead a 1/2" to 15mm adapter (?).

Compression is the better way to go, IMO, and if you have both a metric fitting and an adaptor with you then you'll be ready for different pipe sizes.

Is there an easy way to tell whether the existing copper rising main is 1/2" or 15mm? The house was built in 1968?

That makes it a near-certainty that it's imperial gauge, because the metric standard took effect in 1971, but that wouldn't automatically make it incompatible with metric pipe.

However, be aware that the OD of imperial pipe can vary, since 1/2" refers to the ID, so might hit a snag and have to rub down the pipe to get a 15mm olive onto it.

{Edit: corrected the quoting.}

 

[Tim10]

I've made plenty of capillary joints before, but only on new, completely dry pipes. After further looking into things and realising how much of a problem drying the old pipe might be, I've decided to go for a straight couple compression fitting. It'll be a lot quicker and easier, I won't have to worry about freezing or drying out the pipe, and as the connection will be below the kitchen floor, it'll be out of sight anyway so won't matter how it looks!

I can't avoid cutting the pipe in 2 places, immediately above the old stopcock, and below floor level before the stopcock to remove that section. I have a proper pipe cutter for cutting the rising main under the house, but will have to use a junior hacksaw to cut the pipe above the stopcock as there's not enough room here to use the pipe cutter. I'll make sure I go steady!

Can you get imperial to metric compression adapters? I've never seen them, only 15MM to 15MM metric, or 1/2" to 1/2" imperial. I've fitted various 15MM compression fittings to the existing pipework in the past, and don't recall ever having any problems. I was once told that the size difference wasn't a big issue with compression fittings as a perfect fit isn't necessary as it is with capillary fittings.

If metric to imperial compression adapters are available, does anyone have a link?

Tim

 

[Softus]

I've decided to go for a straight couple compression fitting.

I think that's the wise choice.

...will have to use a junior hacksaw...

Can you not get a pipe slice to fit? Especially if you make the lower cut first?

Can you get imperial to metric compression adapters? I've never seen them, only 15MM to 15MM metric, or 1/2" to 1/2" imperial.

That was a moment of madness on my part - I was temporarily thinking of making onto Alcathene/MDPE - please ignore what I said about an adaptor, but it's still possible that the OD wouldn't quite inside a 15mm OD olive without some wire wool and elbow grease.

 

[Tim10]

The reason why a junior hacksaw is because I've got one of those to hand, and the 15 or 20 quid a pipe splice would cost seems a lot for something I'll only use once or twice, unless you think I'm likley to run into problems with a junior hacksaw? I fitted a stopcock further up the same rising main in the aring cupboard about 15 years ago to shut off the water supply to the cold water cistern in the loft. I cut the pipe with a junior hacksaw then without any problems, although that's no guarantee I won't run into bother this time...

It's a while since I've done any plumbing work on the existing pipework in our house, and can't remember if I encountered any problems fitting 15MM olives, but have definately always got them to fit.

Is the tightening of the compresion joints where they connect to the existing rising main likely to cause any problems?

Tim

 

[Softus]

...the 15 or 20 quid a pipe splice would cost seems a lot for something I'll only use once or twice, unless you think I'm likley to run into problems with a junior hacksaw?

I get the impression that you're careful, so if you don't have a pipeslice then hacksaw will do. Leave enough pipe above the cut to make another in case you have to.

Is the tightening of the compresion joints where they connect to the existing rising main likely to cause any problems?

A very good question. The risk is of the pipe folding when you compress it, so go gently and be generous with the PTFE tape, wrapping it flat around the point where olive meets pipe (on the wet side, not the capnut side).

 

[Tim10]

There's room for error on both sides, so if I do mess it up on the first attempt I can start again. I'll be going for the recommended finger tight then one full turn with a spanner. Hopefully that, and the PTFE tape which I always use should make a sound joint.

Thanks for the help and advice.

Tim

 

[Softus]

You're welcome Tim - I'll be interested to hear how it all goes.

 

[chr15]

Regarding the size of old 1/2" pipework,there is a size that can cause you a problem and best be prepared for it. It looks like 15mm or 1/2" but no amount of cleaning or rubbing with wire wool will get the size down enough. You can get an adapter in compression for it and it is 16mm gauge to 15mm. Not much i know but enough to cause you problems,I encountered some of this a few years ago on a friday night after cutting into someones rising main,the first thing I noticed was that the pipeslice felt tighter than usual but still went on the pipe and cut it but could I get the olives or the compression fitting back over the pipe? No way,tried filing it and allsorts. Anyway found out the next day from an old foreman of mine that you can get these '16' gauge fittings which are made for this pipework,if your lucky you will find them in any of the main well known plumbers merchants,that where I got mine from and I always keep a couple with me now. Good luck.

 

[Tim10]

As I mentioned yesterday, I did manage to fit a new stopcock further up the same rising main about 15 years ago, and have fitted various other compression fittings to the existing pipework in our house. But I can't remember how difficult it was to get the olives on as it's a few years since I last tried it. I suppose even things like size tolerences of different manufacturers of fittings and pipe could make a difference. If there's only a 1MM difference between metric and imperial pipe, a manufactuing difference of a fraction of a millimeter could mean the difference of just managing to get the olive on, and not being able to. I think my best plan of action would be to ask for advice when I buy the parts.

It'll probably be the weekend after next before I get a chance to do the job because we're having the new boiler fitted this weekend and I wouldn't want to get in the way! I'll let you know how I get on...

Tim

 

[Tim10]

Well, we had the new combi boiler fitted last weekend. Of course, the fitter needed to turn the water off, so used quite a neat device, a handle that fits over the broken spindle. It's basically a small piece of spindle with a normal stopcock handle on one end, and a socket, which fits over the filed square end on the spindle of the broken stopcock on the other end. It works perfectly well, turns easily enough, and he left the handle with us. I've never seen anything like that before!

Anyway, I've decided, for the time being at least, to leave things as they are. We have a perfectly useable stopcock, the only problem is the handle/key is quite loose, but if it's kept on the stopcock itself, it's not going to get lost, and we don't have to mess around looking for a spanner to turn it.

If we ever have any problems like the handle dropping off and getting lost, then I'll replace it. For now though I fitted a new earth bond to the pipework above the stopcock, and re-fitted the kitchen units.

Right thing to do?

Tim

 

[Softus]

Right thing to do?

Abso-blooming-lutely!