Old boiler cables.

[D4N1EL]

Hi,
A few years ago we had a new central heating system fitted, old hot water tank taken out and replaced with a new combi boiler in a different location.

The installers left all the wiring just hanging about and the timer connected. At the time I turned the switch off on the fuse board, put chock blocks on the end of the cable and wrapped in insulation tape and gaffer taped them to the wall out the way. The timer is still powered on, no exposed wires or terminals so I left that.

Now years later and we are decorating, the other half what this cupboard made usable and not just full of junk.

What do I do with these wires?

 

[ericmark]

It is always a problem removing old wires where some relay, thermostat or timer is involved, as you can test for dead, and while working they become live, I have been caught out as an electrician and cables need to be removed when nothing is running, just in case. You can remove, but often easier to fit socket back boxes and blanking plates.

 

[D4N1EL]

That sounds like a quick easy fix, that won’t leave an unsightly mess.

I’m assuming the wires inside the back box is safe enough to be left in a chock block and taped up?

 

[ericmark]

Yes you need a tool to assess so complies, or use a wiring centre which already has the chock block fitted. Or any other junction box.

 

[BS3036]

But don't use tape...

 

[EFLImpudence]

Why not fit a socket back box - and socket?

It might be useful?

 

[SUNRAY]

It is always a problem removing old wires where some relay, thermostat or timer is involved, as you can test for dead, and while working they become live, I have been caught out as an electrician and cables need to be removed when nothing is running, just in case. You can remove, but often easier to fit socket back boxes and blanking plates.

Several times I've isolated & locked off and tested for dead. But the system had auto back-up so repowers from a different source. At least 3 times and of course nobody thinks to mention the facility and it's not always obvious.

Domestic heating systems are notorious for the unexpected.

 

[JohnW2]

Several times I've isolated & locked off and tested for dead. But the system had auto back-up so repowers from a different source. At least 3 times and of course nobody thinks to mention the facility and it's not always obvious.

Silly though many 'labels' are, that is surely a situation in which Warning Labels/Signs definitely are required?

Kind Regards, John

 

[SUNRAY]

Silly though many 'labels' are, that is surely a situation in which Warning Labels/Signs definitely are required?

Kind Regards, John

Absoooooluuutaaallllly agree.

Chances are I could have indeed missed such a label in amongst the plethora of useless uninformative labels that seem to smother kit these days.

On one control panel I was called to fault find on a short while ago someone had gone to the trouble of identifying the voltage on every front panel switch and placed a sticker "DANGER HIGH VOLTAGE" with the triangle and lightning symbol on front and back of the switch for those with 230V, which accounted for maybe 40-50% of the switches.

I asked who fitted the labels and found it was their H&S surveyer.

I presented the job sheet for a signature then turned to leave, explaining the H&S inspector was either incompetent or the less likely option had actually discovered an incredibly unusual, and potentially dangerous, panel which was actually high voltage, but eithr way he had prevented me from opening the doors as I'm not qualified to work on high voltage systems.
They weren't impressed with receiving an invoice for an aborted visit as nobody on site was able to confirm the voltage present.

 

[JohnW2]

Absoooooluuutaaallllly agree. ... Chances are I could have indeed missed such a label in amongst the plethora of useless uninformative labels that seem to smother kit these days.

Quite so - the 'crying wolf' problem.

.... On one control panel I was called to fault find on a short while ago someone had gone to the trouble of identifying the voltage on every front panel switch and placed a sticker "DANGER HIGH VOLTAGE" with the triangle and lightning symbol on front and back of the switch for those with 230V, which accounted for maybe 40-50% of the switches. .... I asked who fitted the labels and found it was their H&S surveyer. .... I presented the job sheet for a signature then turned to leave, explaining the H&S inspector was either incompetent or the less likely option had actually discovered an incredibly unusual, and potentially dangerous, panel which was actually high voltage ....

Surely the former (incompetent)? Was (truly) "high voltage" present anywhere within the installation (I suspect not)?

Kind Regards, John

 

[SUNRAY]

Quite so - the 'crying wolf' problem.
Surely the former (incompetent)? Was (truly) "high voltage" present anywhere within the installation (I suspect not)?

Kind Regards, John

I'm totally convinced it was incompetance and equally well I'm convinced there is very little likelyhood of finding 'high voltage' on site.

However it was my first [and only] visit to the site and
1. as I'm not HV trained, and
2. certainly didn't have any HV PPE with me and
3. there was no sign of any on site and
4. no one on site had a clue what voltages are present in the panel [or the site generally]
I was not prepared to go any further than a quick peep for any evidence of any drawings. Seeing the plethora of additional 'HIGH VOLTAGE' stickers on the switches internally I closed the door immediately.

H&S and all that, I did my personal risk assessment as mandated by HASAWEA1974 and moved on. I even got home in one piece, which is a target of the act.

 

[D4N1EL]

Why not fit a socket back box - and socket?

It might be useful?

That would involve another question about how to tell if the wires are good enough. I’m more then capable of reading a wire and asking the question, it’s just not worth it it for a plug socket in a cupboard that won’t get much use.

 

[JohnW2]

That would involve another question about how to tell if the wires are good enough. I’m more then capable of reading a wire and asking the question, it’s just not worth it it for a plug socket in a cupboard that won’t get much use.

Fair enough, although if it is PVC cable, and if it were working OK when last in service (to power the immersion), then there'sno reason to think that the cable would not be 'good enough' (to supply one socket).

If you really do not 'want' it, then the usual advice would be to disconnect the other end of the cable (from the CU/'fuse board/box'), after which you could do anything you wanted with the (now 'dead' and unused) cable. However, looking back, you wrote:

.... The installers left all the wiring just hanging about and the timer connected. At the time I turned the switch off on the fuse board, put chock blocks on the end of the cable and wrapped in insulation tape and gaffer taped them to the wall out the way. The timer is still powered on, no exposed wires or terminals so I left that.

... which leads me to wonder what is powering the timer, and what the cable you have been talking about actually is. Perhaps you could clarify?

Kind Regards, John

 

[D4N1EL]

Yeah, I thought that something was wrong. When I turned the boiler switch off, I expected the timer to go off. There is wires going to the timer, but none coming from the timer, there is wires hanging from the ceiling.

 

[EFLImpudence]

Have you turned off a 'switch' - circuit breaker - for 'Immersion' or 'water heater'?