Electrics and Heating Pipes

[mylittlehouse]

Hello All
In the last two weeks i have had my house rewired and all new plumbing put in.

I have noticed that in places the heating pipes (plastic) and electric cables are running in the same place.

One place i noticed that the cables were quite warm and even touching the plastic pipes so i moved them apart.

I did notice a bit of brown smudge on the cable where they had been touching but this just wiped off so i assume that was nothing. please correct me if i'm wrong.

Should i be concerned? Will lagging the pipes reduce the temperature where they run together?

Please Help

Thanks

 

[ericmark]

Cables are rated to run at different temperatures 60, 70, 90 degrees are common ratings and central heating water is normally on the limit of 70 degrees which is limit for a metallic item which can be touched maybe up to 80 degrees which is limit for a part which need not be touched for normal operation.

Now although with no power going through the cable this is not a problem once there is power the amount it would need de-rating would mean there would be a problem.

So likely there is a problem but because there are variations without seeing the installation one could not be 100% sure there is a problem.

I have had in the past where plumbers have routed their pipes too close to cables but one would hope electricians would not route cables close to hot pipes.

With standard grey cables I would want to see a gap between pipes and cables. Where the cable was part of a ring main or other high current circuit this would be important. However for example the central heating control cable which carries only a control signal and very little current the cables being close would not present a problem.

 

[mylittlehouse]

Hi there
well the space between the joists is 6" and there is a cooker main, lighting and ring main

i have been looking at lagging and i see that there is some really thick stuff that combats against heat loss so i think i will get some and run it where the cables are near each other just to be safe.

 

[ban-all-sheds]

Make sure you put it round the pipes, not the cables...

 

[mylittlehouse]

lol thanks for the advice it did make me laugh.
I think i will install Armaflex with a 19mm wall to be on the safe side.

 

[Taylortwocities]

Not like this, is it?

Untitled

• Taylortwocities
• 12 Oct 2008
• 10

 

[1john]

You could provide a barrier with some plasterboard off cuts also.

 

[sparkwright]

Not like this, is it?

Untitled

• Taylortwocities
• 12 Oct 2008
• 10

That is a classic example of how rough plumbers can be. In an ideal world, the plumber should run his pipes first, then the electrician can follow.

As the picture shows, what often happens is the electrician will lift floorboards, drill holes and run the cables in.

Then the plumber will come along, and somehow feels obliged to 'follow' the electrician's route. Partly because he won't have to lift any more floorboards. He will then notch the top of the joist above the holes, and weaken the joists. Lay the pipes in, touching the cables of course, and sometimes damage a cable or two in the process. He will also try to burn as much woodwork as he can with his blow lamp. Once he has laid his pipes it's just about impossible to get at the cables again for any alterations.

Some plumbers are quite good.

 

[bernardgreen]

Having lost almost all the timber from centre line to the upper surface that joist has lost a lot of its strength.

Plumbers ? ?