new 22mm hep cold mains supply

[sav]

hi all

just looked at a job where they want a new cold mains supply run outside and they want the sparky to fit trace heating to the mains supply as the old supply had burst (no lagging)

what im thinking of doing is running the new supply in 22 hep twin wall with lagging (19mm wall) then the sparky can fit his trace heating to the hep, question is is that ok? i know hep can take temps up to about 90c so in my mind it should be ok.

please feel free to say if its ok or not just need to run it pas someone else lol

 

[GQuigley67]

what about alcatheyne ?

 

[Centralheatking]

I would go with GQ - alcatheyne is much more robust - and the fittings are better for underground
i think

centralheatking

 

[TGor]

It depend on the wattage of the trace heating .. som types can get quite high surface temperatures and if in contact directly with plastic pipe then could cause problems .. need to discuss carefully with the sparky ..

 

[WHPES]

Read through previous posts about Hep pipe. It has proved to be a poor performer in frost which is why I no longer use it. MDPE is the best for your job.

 

[GQuigley67]

alcatheyne all the way 25mm

 

[sav]

so if i put alcatheyne in with 19mm wall lagging would i need the sparks to even bother putting the heat trace in or not?

i was thinking hep as i know it can have warm water in it and as i do not know what temp the heat trace runs at i dont want the alcatheyne to melt or somthing

its not going under ground its going high lvl in a cable tray out side

 

[GQuigley67]

yes but it is outside so alcatheyne is stronger than hep much thicker material. Best checking with the specs and see what its heat tolerance is, I'm sure It'll cope the heat tracer only kicks in at 4 degrees celsius to prevent freezing and it would probably only heat up a few degrees i believe, again best checking with sparky.

all in all I think alcatheyne is the best choice

 

[sav]

looks like alcatheyne then

any one know what the hottest temp it can take befor melting?

i will get a price on it all tomorrow and go from there.

thanks for the info lads

 

[oldplumber]

you may wish to check water regs , theres a reason pipework is underground at a depth of 750 to 12350mm, it wont freeze, common
sense really.

 

[BenC]

i beleive the regs would be, pipe must be fully suported and fully insulated and away from any means of being damaged.

 

[markproperjob]

Dont bother with trace heating.
i installed 25mm blue alc around our farmhouse as impossible to bury the final 30metres, its clipped to stone walls around 300mm off ground level, and is continuously lagged with 23mm split lagging, even the spurs for upstands and the chicken drinkers come off the main run and are lagged the same way.
recently, the temperature dropped so drastically it hit minus 6 and my isuzu's brakes froze solid, but our water supply remained un frozen, even though its fed from a well at less than 1bar pressure with minimal draw off.
i think heating the pipes is overkill, but there again, what part of the country are you in?
us southern pastie chasers have only recently gotten frostbite!!

 

[sav]

i cant put the pipe work under ground as its going in a calbe tray out side a wearhouse, im in devon gets cold here but not that cold i guess