Overwinter - MPDE on the surface

[lloyda]

I'm looking at using black MPDE run the length of the garden to connect to an irrigation system. It will be teed into the feed for an existing outside tape, with an associated isolation valve and double check valve. It is not possible to bury the pipe for most of its length, so intend to drain over the winter. Although the pipe will run downhill (slightly), should I put a drain valve after the isolating valve to allow air in? Before or after the double check valve?

Thanks

 

[MeldrewsMate]

Firstly, the acronym is MDPE (medium density polyethylene).
I suggest you install your manual air admittance valve as close to the start of the run as possible, and be prepared to blow or use compressed air to evacuate the water over winter....double check valves with trapped water inside don't react well to freezing conditions.

 

[muggles]

Just opening the tap at the far end should be enough. I've got a similar setup at home and forgot to even do that this year. All was fine when I came to use it again in the Spring