Blanking Caps for Washing Machine Valve Unions.

I think this is the right place for this post as it's about piping components. If not, please forgive me.

I've incorporated a pair of washing machine valves/unions in my kitchen refit plumbing.

There won't be a washing machine connected to them for some months and even then the hot one may be unused as lots of washing machines these days seem to be cold-fill only.

These valves only have a small-bore but if you happen to turn one on by mistake you don't half get a torrent of water. So, for extra security, I thought blanking caps would be a good idea.

I looked in various Plumbers' Merchants but didn't find anything suitable so I thought I'd have to set to work on the lathe and turn a couple up from a suitable grade of brass or maybe nylon, using the fittings salvaged from an old pair of washing machine hoses as a model.

Then I thought I'd try filling a couple of nylon hose end fittings with hot-melt glue. It sounds like a bodge but the glue appears to have bonded to the nylon OK and the shape of the plug of hot-melt is right to retain it in the fitting body. So I'll try them out and report back.

I have wondered whether the hot water would be too hot for the hot-melt glue but I think the glue melting-point is sufficiently high.

Comments invited as long as you don't claim to be so perfect that you've never turned on such a valve by accident!

3/4 bsp brass caps are what you need

When you say you've 'looked' in various merchants- have you actually asked for caps. They're readily available in brass or iron for pennies.

Kev beat me to it!

only by 2 mins

Fair comment, chaps.

Don't fancy black iron, though.

I'll have another look for brass caps next time I'm out and about. In the meantime, I'll fit my economy models as a temporary measure.

Neither of you said whether you bother to blank unused washing M/C valve unions; I'd be interested to know.

On a related topic, I thought a well-known supplier, often linked-to from DIYnot, listed a washing machine valve with a wall-plate. They don't seem to list them now; did they not catch on?

I've purchased about three different types of blanking caps over the last couple of years. One method included a new olive for copper pipe at 15 or 22 mm, this meant replacing the existing fitting with the blanking cap. ( Wickes)Another type was solid brass at 15 or 22 mm which included the shape of the olive, this was for use instead of the pipe and blanked off one side of a fitting. ( Focus Do It All ) The last type I got recently was a recessed solid collar with internal thread to match the fitting and incorporated a rubber disc.( B & Q warehouse).
I can't see how the hot water will be too hot to affect the glue.If it's blanked off there won't be any hot water at valve, it only gets hot when there's flow through the valve.
Ah I should not have responded! cause I ain't turned a valve on by accident. I did however turn a new valve on and nothing happened and it turned out there was no hole through the ball. Perhaps you should fit a couple of these ( Bought at Wickes ' special purpose to test plumbers ability I think) ).

Hi there, mandate, thanks for your post.

<for use instead of the pipe and blanked off one side of a fitting.>

I think we're at cross purposes in the first part of your post. The blanking caps I was looking for were to blank the port on the washing machine valve union where the washing machine hose connects, not to blank the end of a run of copper pipe.

<I can't see how the hot water will be too hot to affect the glue. If it's blanked off there won't be any hot water at valve, it only gets hot when there's flow through the valve.>

My logic exactly.

But the other guys are right. I ought to have a more thorough search for 3/4 BSP brass blanking caps.

It's just that with all the takeovers and mergers the range of fittings available has diminished over the years. I'd got the impression that parallel thread BSP brass caps and plugs were among the casualties.

I've still got catalogues issued by the big names back in the sixties when they made fittings with anything up to four ends with any combination of sizes, direction and connection (compression, BSP male, BSP female or plain spigot) that you could imagine. Try to find some of those nowadays. (OK, so they were Imperial and now we're Metric; I don't think that defeats my point.) The common fittings are so heavily discounted in some suppliers that nobody can afford to stock the complex ones. So the makers can't afford to make them anymore. But that's a different issue from my original post.

Know what you mean - try to buy a corner tee.....

BUt 3/4" washing machine tap caps are about 25p and a ballvalve washer to go in them about 10p.

If you want a strong tap which won't get knocked use an outside tap (3/4 bib tap) in a backplate elbow - much better.

You can of course bin the nut and olive from a normal (craap) wm tap and screw the 1/2" thread straight into a backplate elbow. Use thread lock compound and it'll never move unless heated with a blowlamp.

chris in the ne you will be lucky if the pimply little oinks that stand behind counters even know what a corner t is try getting flared comp fittings

There's information about these blanking caps for washing machines here http://www.whitegoodshelp.co.uk/wor...-when-connecting-a-cold-fill-washing-machine/ including a link to order one online if required.

think he might have got one by now

check the date of the post