Help with Wiring Regs Please

[TheScullster]

Hi all

Don't have the OSG to hande, can anyone please advise?

Had central heating upgrade done and noticed the following wrt cabling.

Feed to boiler runs from fused spur outlet clipped into shallow chase - no conduit protection. Power and control cables from boiler to airing cupboard run through a cavity wall (formerly an external wall prior to kitchen extension). No sleeving or conduit to protect the cable span across the cavity. Cables clipped to wall adjacent to pipes - not in conduit/trunking. Pipes will get hot - should cables be in conduit to reduce heat take up?

Strangely, airing cupboard wiring is neat and concealed in trunking!

TIA

Phil

[John White]

This sounds like a fairly typical CH installation.

As you point out there are a couple of items that are not "best practice", but frankly I wouldn't worry about it unless there is any obvious mechanical damage to the cables.

Standard PVC cables are specified at 70 degrees C, and heat resistant cable at a higher value. Given the current flowing in a CH system and derating for temperature, the cables are probably still well within specification.

John

[TheScullster]

"John White" wrote

...........snip..............

Thanks John

Regrettably, I am no longer surprised when so called "professionals" do shoddy work like this. That reminds me, must check the CU for the "dissimilar cable colours" label when i get home.

Phil

[Christian McArdle]

Provided that it runs in permitted zones, then this is perfectly OK.

No problem at all. You can certainly span the width of a cavity with PVC cable without further support. As it is now an internal wall, cavity bridging is of no relevence.

Depends on the distances involved. Conduit won't help much. The cables would need to be further away. Cables for central heating will be VERY overrated anyway. Typically, 1mm cable is used, which can take many times the actual current, giving much scope for thermal derating.

Christian.