Is it ok to mix MDPE and copper on a central heating installation? I'd like to use copper everywhere but some locations are a right pig to get at.
I'm (or rather SWMBO) is thinking of putting a curved rad in the bay! I'm not so keen on grounds of cost and logistics of getting the thing in place (upstairs). Also trying to curve a copper pipe of that radius neatly does not appeal so I thought MDPE might be the thing? tia
If you mean polyethylene or polybutylene type pipe, then that's fine, MDPE (The blue mains water stuff, usually in 20 or 25mm) is not OK for hot water AFAIK
this
OK
This is not
Yes, but probably not for your application.
I've mixed copper and PEX, but the PEX was under the floors (where it's at risk of damage by rodents gnawing it).
It looks crap if on view. The coefficient of linear expansion is very big, compared to copper, about 5x ISTR.
You can put it in straight, it'll go wavy when the heating is on.
MDPE? Are you sure?
That's blue pipe normally used for underground cold water.
PEX or PE are the usual types for HW inside.
^^^ PB (Polybutylene) sorry.
Always thought MDPE stands for medium density polyethylene. So why would polyethylene be ok if medium density is not?
MDPE is solid.
PEX and PB pipe are layered, with an O2 barrier - particularly important with heating systems.
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