MDPE to Hep2o plumbing

[Roz]

Hello another plumbing question but I'm getting there! 

 

I'm doing the garden studio plumbing in 15mm Hep2o. I need to pick up a few last things so thinking ahead to how to actually connect it to the MDPE pipe that runs under the ground from main house. 

 

The MDPE currently pops up outside the back wall, so I was thinking to have it coming through the wall low down, but I don't know which connectors to use. Hep2o don't seem to do many MDPE connectors and I'm not sure when I can use Hep2o with other brands. I'm trying to avoid copper but should I use copper between two different brands maybe... I'm getting confused by all the options

 

Also should a stop cock be outside the wall before the pipe comes through. Should the pipe come through in MDPE or in Hep2O...etc. 

 

lastly I ran my pipes about 60cm from the floor because it made sense at the time... does it matter they dont run along the floor? I can change them if I have to

Edited August 25, 2019 by Roz

[MrMagic]

I'd keep as much of the pipework internal as possible to minimise risk of freezing etc. Come through the wall in MDPE, stopcock, then Hep2o

 

Provided you follow the instructions you can safely use brass compression fittings with Hep2o, best with copper olives. I used a 20mm -> 15mm standard brass compression fitting to go from MDPE -> Hep2o.

 

JG Speedfit also make a dedicated fitting for this but as you say, the 'recommendation' is to not mix the brands - but I expect it would probably work... best let one of the more learned folks advise there.

[Russell griffiths]

I personally would dig around your mdpe to get a bit of movement, then bring it up through the floor into either a cupboard or a void in the wall, then connect an mdpe stop valve then a reducer from mdpe to hep, then onwards and upwards. 

Bringing it through the wall will require multiple mdpe bends which are bulky and make an ugly fitting, I wouldn’t use hep outside as you will need to insulate it heavily.