Plumbers. Bless them.

[dingodeano]

looks like you sparks are all wrong then.

It's perfectly acceptable to use an insulated green and yellow for heating controls, provided it's oversleeved and identified.

Confirmation from NICEIC, and building control, still waiting for John at NAPIT to reply.

Uninsulated earths cannot be used.

Get to grips with the regs guys.

I will concede when you give us the names of the people of NICEIC and Building control and or show us what they replied, tell them you are going to put it in public domain, As you have with john at NAPIT who has confirmed what i believe to be the true interpretation.

 

[londonboy]

The NIC do not write the regs.

If I had an electrician working for me and I caught him sleeveing the earth, he would be shown the door.

I have worked for numerous heating contractors and its forbidden on each firm.

 

[Iggifer]

Update 2-1 for the plumbers at the moment.

NAPIT replied, but subject to change.

The earthing conductor should not be over sleeved to indicate it as any other conductor than what it is, identification of the ends is all well and good but if someone where to break into the cable along its length for whatever reason, then the cpc would for all intensive purposes at that point would be the earth and connections would be incorrect and possibly dangerous. All conductors should be identified as BS7671 chapter 51

I think he meant for all intents and purposes

 

[ecowarrior]

On a new install there is no excuse at all for sleeving an earth.
I suspoect the exclusion is to cover the 50 years of bad practice that have left probably millionsd of households with this issue. It is unrealistic to expect a sparky or a plumber to rewire the heating controls in old houses. Its just not going to happen.
Better to give in - and get the conductors sleeved so at least the next bloke will see what's happening. My own procedure is to sleeve live neutrals with brown & live earths with red. Its rare to se bare earth as a live conductor - but with boilers needing pump over run - it does sometimes happen.
Do u sparkies ever consider pinched neutrals on the heating ccts when upgrading to R17? If u wire it in the summer with the S/Y plan off - u wont know there's a problem till the heating comes on & both RCD's trip!

 

[vulcancontinental]

I am not a sparks but interested as I have wired up and adapted heating controls by sleeving the GY at terminal ends in extremis. I know there's controversy here but can I ask;

1: Isn't there a maximum length that flex can be run before it has to be cable? (For some reason I seem to recall 2m and if so both terminations of the cable would be visible to someone cutting into the centre).

2: Is there a cable, say the equivalent of 2.5 twin and earth or 1.5 twin and earth that is available with sleeved earth? (If not then the problem doesn't exit because the unsleeved earth conductor cannot be used for anything else, though I to have seen it used for neutrals may times and changed it).

 

[EFLImpudence]

1: Isn't there a maximum length that flex can be run before it has to be cable?

No.

(For some reason I seem to recall 2m and if so both terminations of the cable would be visible to someone cutting into the centre).

2: Is there a cable, say the equivalent of 2.5 twin and earth or 1.5 twin and earth that is available with sleeved earth?

No, that would be flex. There is flat Three core and earth.

(If not then the problem doesn't exit because the unsleeved earth conductor cannot be used for anything else, though I to have seen it used for neutrals may times and changed it).

The answer to '1' unfortunately negates this.

 

[doitall]

A good discussion I think is going on.

Probably change when BAS finds out.

 

[EFLImpudence]

No, read 412.2.3.2

 

[doitall]

No, read 412.2.3.2

What does 410-3-9 say

 

[londonboy]

A good discussion I think is going on.

Probably change when BAS finds out.

Shall I ask BRE, BSI and Elecsa on Monday.

You may as well ask the milkman for his opinion.

None of them write the regs.

Ask the IET and come back to us.

 

[doitall]

Why would the Information Engineering Technology know

How the HSE.

BRE write part P so must have a clue.

Has anyone read 18 edition yet

 

[EFLImpudence]

No, read 412.2.3.2

What does 410-3-9 say

Nothing of relevance

unless you are indicating that a metal enclosure can also be used as a line conductor as long as it is identified.

 

[PrenticeBoyofDerry]

Has anyone read 18 edition yet

I've read it, but don't want to spoil the end for anyone

 

[PrenticeBoyofDerry]

1: Isn't there a maximum length that flex can be run before it has to be cable? (For some reason I seem to recall 2m and if so both terminations of the cable would be visible to someone cutting into the centre).

There is no maximum length that flex can be used, in fact using the correct provisions you could rewire a property with it.

 

[xdave]

Why would the Information Engineering Technology know

The Institution of Engineering and Technology publish BS 7671.