MDPE copper unions?

[Tim S]

Arrg. Too many options...

I need one underground 15mm copper to 25mm MDPE union and one 22mm copper (or 3/4" BSP) to 25mm MDPE union.

JG Speedfit say their ones are no good underground.

Another says "do not use where end loading is possible".

Another suggests that you need 25-22 reducers before you can use the bunch of washers and widgets.

All I need are simple, buriable robust adaptors.

Any recommendations?

Ta

Tim

[Andrew Mawson]

Personally I wouldn't put straight copper pipe underground. I'd bring it into the building and convert to copper indoors where the risk of corrosion is much reduced. Beware of brass underground fittings - the zinc is leached out (dezincification) - use the mnore expensive bronze ones.

AWEM

[auctions]

Toolstation have a decent selection of stuff. One option is the universal adaptors which replace a nut on their coupler:

I remember they replace a nut a size bigger than you'd expect, so the 15mm goes on a 25mm fitting, the 22mm needs a 32mm.

They also do MDPE to BSP fittings which would be simpler as long as you're happy burying a compression to bsp fitting.

A

[Tim S]

Andrew Mawson coughed up some electrons that declared:

Hi Andrew,

The copper is already underground - it's the main supply, in plastic covered

15mm copper.

The MDPE is a rerouted section for a new incoming position. Down the line, when I have a digger, I plan to take the MDPE all the way to the road, where the water company say they will happily connect it to my c*ck for free.

I'm taking the chance to plan for upgrading the pipe bore at the same time.

Cheers

Tim

[Dave Osborne]

BES any good?

[Tim S]

Dave Osborne coughed up some electrons that declared:

Cheers

Tim

[Tim S]

[e-mail] coughed up some electrons that declared:

OK. Thanks for that. I'm veering either towards teh BES fitting,

or this:

Subject to Andrew's warning about dezincification of brass, I also like this idea.

I will be putting a tiny inspection doobrey over this joint anyway as it's right next to the house and if it fails, I want to know about it (rather than waiting for the house to fall over).

Cheers

Tim

[Appin]

The message from Tim S contains these words:

Sounds a bit painful :-)

[Tim S]

Andrew Mawson coughed up some electrons that declared:

That's interesting - I thought the water main had been replaced in the late

90's.

Perhaps the end had merely been moved hence the weirdy underground joint to copper...

[Frank Erskine]

On Fri, 5 Jun 2009 22:53:42 +0100, "Andrew Mawson" had this to say:

I wonder why. My black polyethylene feed pipe was fitted around 1972 and hasn't given any trouble (at least in the last 26 years that I've owned the place).

[<me9]

Colour coding. You can't mistake more modern pipe for an electricity cable. (Or worse still, the other way round.)

[Tim S]

Tim S coughed up some electrons that declared:

Righty ho...

Done the job:

Inside the house, 25mm MDPE to 22mm copper stopcock is done with

part number 11330

Very pleasing and simple and slim (ish).

First solder the brass 22mm tail into a solder coupler and a bit of 22mm pipe on the other side. Lots of heat needed but easy with a normal blowtorch.

Then insert copper insert into MDPE pipe, nut and olive on outside, assemble and do up *very* tight (it's a big olive and needs some welly).

Result - a very neat joint. Stick compression stopcock on the end.

MDPE to 1/2 inch PE: same page, part 13544.

Potentially easy (that thing has a bloody big doughnut o-ring in it - it would joint to anything, as it in fact claims to. Main difficulty is doing the extra 1/8 turn after hand tight on the MDPE and the extra 1/2 turn on the other side. You need a strap wrench (or risk stilson chewing the plastic up). Still a bugger to hold the fitting though - used pump pliers, seemed to manage without wholesale destruction.

Not recommended for internal connection to copper - it would work, but it is

*huge*!

Pressure teested to 10.75bar (used one of those pushfit jobbies:

the pathetic 4 bar guage swapped out for an 11 bar one off this:

blew up the footpump, obviously advised helper to stay out of the firing line of any bits that may becomed detatched.

But it held pressure for 5 minutes, so that's good enough - and more or less satisfied the "test to 150% of working pressure" recommendation of the MDPE-random-crap-adaptor (water pressure is 7.5 bar).

We now also know that the road stop c*ck turns off properly as we were pressure testing against that!

Stuck the full bore lever valve and pressure reducing device on. Cursed trying to get everything to line up.

Mounted the stack on 3 mentally strong solid brass "hospital" saddle pipe clamps, packed off the wal with thick square building style plate washers to line up with the MDPE clip and hole in floor.

Going to retest tomorrow and test the throughput of the PRV to see if it buggers up our flow rate (40l/min without) or not.

Cheers

Tim

[Tim S]

Tim S coughed up some electrons that declared:

On an aside,

I used one of these as my PRV:

done some flow measurements. My system is new-ish c*ck in the road (blue water meter type witout the meter), 1/2 inch PE black pipe for about

15m to the house, jointed by me into 1.5m 25mm MDPE then into a 1/4 turn full bore lever valve (inside c*ck) then into the above PRV. Static pressure of mains is 7.5 bar.

For testing, I stuck a bit of U shaped 22mm copper onto the top pointing down at a 14l bucket and timed the fills.

Flow rate is 50l/min regardless of pressure setting, everywhere between 2 bar to 6 bar (the limits of the PRV, more or less).

Not sure I'm going to bother with upgrading the main to the road now. I think I have a more than adequate flow for my heatbank with direct hot water :)

I'll keep all of my end in 22mm until the final drops to each usage point, and do those in 15mm.

Also, 4 bar seems a nice setting. Good hose jet and doesn't blow the taps off! And seems to regulate the pressure OK at 4 bar even with a tap going full blast.

Cheers

Tim

[Jim]

I'm using one of these Caleffi valves at the moment to reduce the water feed into the caravan we're living in (whilst our extension is done) down to 1 bar so the plumbing doesn't blow. You can pick them up on ebay for about 10 quid.

[Tim S]

Tim S coughed up some electrons that declared:

And here are the photos:

[Mike Tomlinson]

In article , Tim S writes

Forgive me, you've clearly put a lot of thought and effort into this, but it's not exactly, um, pretty is it? Do you plan to hide it behind some kitchen cabinets, or... ?

[Tim S]

Mike Tomlinson coughed up some electrons that declared:

Indeed.

And excuse me - it is *very* pretty - all polished up and everything. I'd marry it... ;->

That position was chosen specifically so that little lot can go into the back of a cupboard. A stand alone cupboard to boot, to the right of the cooker, which means that in the worst case, I could remove the cupboard for better access if I needed to do serious work.

But the components are aligned such that normal maintenance like changing teh PRV cartridge can be done from the right side and I doubt it would be hard to swap a new c*ck in. The MDPE has enough slop to drop down an inch if required.

The only bugger is directly above there is an arse load of timberwork, so I may have to bend the riser pipe and route to the right (chrome time).

Cheers

Tim