MDPE connection to tap?

[Weebles]

We have an outside tap (temporary) situated not far from our boundary boxes. Our house 32mm MDPE supply is ready to connect. It can’t get to the boundary boxes (yet) as there is a caravan in the way. What advice please for connecting, potentially to this outside tap (a 15mm copper pipe)? And what should we lag the MDPE with - it’s going to probably be overground for these 5m all winter.  Thanks

[Nickfromwales]

One of these on the end of the MDPE pipe, and one of these with a short bit of 22mm copper between them. Compression fitting means no soldering. You can get the same in pushfit if you want a zero tool solution  

You'll need an insert to go into the end of the MDPE pipe, LINK 

 

Any pipe lagging ( screwfix are cheap enough but only sell the really thin walled stuff ) as long as you tape all the seams / joints well.  

[epsilonGreedy]

I had a 25mm MDPE pipe running 22m to my static caravan last winter. It was uncovered in shallow trenches or overground with no ill effects. The static caravan taps spurted icy slush on a few mornings following a cold night though I think that ice originated from the caravan's own piping. Locals have warned that last winter was mild.

 

At the time @JSHarris advised the good thermal conductivity of water coupled with a stable ground temperature of 8 degrees tends to counteract local freezing points in MDPE. In another thread I posted some water pipe sums that show a couple of toilet flushes will draw subsoil temperature water through 25m of exposed pipe.

Edited September 23, 2019 by epsilonGreedy

[Weebles]

Thanks @Nickfromwales.  Parts ordered.

 

Thanks @epsilonGreedy.  Will lag the MDPE pipe anyway and keep fingers crossed for another mild winter.  We had no problems in the caravan last winter but this will now supply the house where, hopefully, toilets will be flushing regularly enough to keep the water flowing.....

[Jeremy Harris]

11 minutes ago, Weebles said:

Thanks @Nickfromwales.  Parts ordered.

 

Thanks @epsilonGreedy.  Will lag the MDPE pipe anyway and keep fingers crossed for another mild winter.  We had no problems in the caravan last winter but this will now supply the house where, hopefully, toilets will be flushing regularly enough to keep the water flowing.....

 

Keeping water flowing is the key to keeping pipes from freezing.  Doesn't take much flow to keep the water in the pipe above freezing point, as water is pretty thermally conductive, so heat from a slightly warmer area under ground will tend to flow through the water to some degree.  If a pipe's running along the ground, just heaping some earth over it will help a fair bit to keep it from freezing, as it's rare in most of the UK for the soil to freeze for more than an inch or two down from the surface.