cables with CH pipes

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Would it be ok to run two cables for a ring main in with CH pipes as follows.
Total ring board to board 2.5mm T&E, 36m fixed method 1 within a boxing 200mm x 50mm x2400mm containing 22mm CH flow and return and domestic water 15mm Hot and cold.
obviously can keep cables adjacent to cold water pipe and CH pipes furthest away.

Any issues with that?
Thanks in advance
Gareth
 
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Interesting re the temp, central heating pipes carrying water at 65 degrees, maybe high 40s-50s, that was my primary concern.
As for method 1, just clipped to the wall inside the boxing. It's probably got some new designation nowadays
 
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climaflex or similar insulation on the pipes will reduce the air temperature inside the enclosure, and also prevent the cables coming into contact with hot pipes.

lag the pipes first, then measure the temperature. It may affect current capacity of the cable, more so if it is for an immersion heater or electric shower which draws high current for an extended period.

PVC cables can soften and deform badly if they are pressed against hot pipes (this often happens when they are poked into a notched joist together and a floorboard nailed on top).
 
Interesting re the temp, central heating pipes carrying water at 65 degrees, maybe high 40s-50s, that was my primary concern.
As for method 1, just clipped to the wall inside the boxing. It's probably got some new designation nowadays
Clipped direct is reference method C (has been for some time).
The issue is the build up of heat and that current carrying cable will not be able to dissipate heat satisfactory. So the best thing would be to either, reduce the heat in the enclosed boxing, separate the cables be sectioning off, or increase the cable CSA.
 
Thanks for the replies, the current central heating pipes are already in a box following the route and I dangled a temp probe down there over the weekend and it peaked out at 39 degrees.
I think I will do as above and section the boxing off and insulate around the pipes.
I realise it's not the deciding factor, but there will only be 4 double sockets on the whole ring as it's for a loft conversion
 
Interesting re the temp, central heating pipes carrying water at 65 degrees, maybe high 40s-50s, that was my primary concern.
At whatever the CCC is for a cable given its size and installation method etc, the conductor will be at 70°.
 
Interesting re the temp, central heating pipes carrying water at 65 degrees, maybe high 40s-50s, that was my primary concern.
At whatever the CCC is for a cable given its size and installation method etc, the conductor will be at 70°.
Only at the ambient temperature that was used to determine that CCC - usually IIRC 25 deg Celsius.
 
Ah - "etc" in "given its size and installation method etc" was meant to cover all the derating factors which apply.
 
Just to update, separated the central heating pipes from the rest of the boxing with a bit of 2x1 and redid the temperature probe thing. this time it peaked out at 28 degrees, so combined with a bit of insulation around the CH pipes I think I'm happy to go with that.
 

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