Combi boiler to consumer unit

[JohnW2]

Depends how worried you are about the possibility of reversed polarity. Depending on your opinion of the average standard of installation and testing of central heating installs, you may well be concerned about neutral being 240v from the boiler casing

Indeed - and, as I said, even if polarity is correct, the regs seem to take the view that DP isolation is needed for TT - presumably on the basis that, in the absence of (satisfactorily functioning) RCDs to clear the fault, a CPC etc. could, due to a fault in the installation, be at a potential very much above the potential of neutral (or, put the more relevant way around, the neutral could be at a very different potential from the CPC etc.

Kind Regards, John

 

[winston1]

That does not mean there aren't any.

And crucially it does not mean that you KNOW there aren't any, therefore you cannot KNOW that your advice is not, in fact, advising the commission of criminal acts.



Consider that if there was a relevant gas regulation, then a maker could insist that his products only be installed on the third Tuesday of each month by a left-handed red-haired technician, and it would be compulsory to abide by that.

Be interesting if you could find either regulation and link to them.

 

[JohnW2]

Be interesting if you could find either regulation and link to them.

It would, but, given that you two argue about this issue so often, it would be easy enough for one of you to pop over to the plumbing forum and ask if there are any gas regulations which (like BS7671 until recently) insist on compliance with manufacturer's instructions.

Whilst you were at it, you could also ask whether there are any rules/regulations regarding the nature and location of electrical isolation for boilers - although I suspect that may be a matter of 'good practice' and/or employer/H&S-imposed 'rules'.

Kind Regards, John

 

[securespark]

In terms of DP isolation.....folk I know have had people (one Worcester Bosch and the other BG) refuse to service/repair a boiler because of the absence of a nearby means of DP isolation.

That's lobbox.

Because you can use the CU main switch as DP isolation. As I told my safety assessor during an assessment.

It does not have to be local if you can lock it off.

 

[John D v2.0]

It does not have to be local if you can lock it off.

You'd have to, otherwise there would be a high chance someone would come and turn it on again!!

 

[EFLImpudence]

I would think that they merely want a nearby switch so that they can easily frequently turn it off and on to see if what they are doing step by step is working.

That may be a quite reasonable demand but hardly requires rules and regulations to state a switch must be fitted.
Therefore I would presume that boiler fitters would automatically fit a switch on installation so all boilers should already have one.

 

[JohnW2]

That's lobbox. Because you can use the CU main switch as DP isolation. As I told my safety assessor during an assessment. It does not have to be local if you can lock it off.

That's true, as is fair enough provided that those who service/repair boilers carry a means of locking off all possible main switches AND their customers are happy to have their entire installation turned off for the duration of work on the boiler.

Kind Regards, John

 

[JohnW2]

Therefore I would presume that boiler fitters would automatically fit a switch on installation so all boilers should already have one.

I would imagine that those who are (or think they are) constrained (by their employer, rules/regs or whatever) to only work on a boiler if there is a nearby means of DP isolation probably do just that, if/when they are installing a boiler. However, I doubt that the 'requirement' (or imagined requirement) is universal - so someone coming across a boiler installed by someone else might not find such a means of isolation.

Kind Regards, John

 

[ban-all-sheds]

Be interesting if you could find either regulation and link to them.

I don't need to - I'm not the one asserting that there isn't one.

 

[ban-all-sheds]

It would, but, given that you two argue about this issue so often, it would be easy enough for one of you to pop over to the plumbing forum and ask if there are any gas regulations which (like BS7671 until recently) insist on compliance with manufacturer's instructions.

Then let Winston do it - he is the one assuring people that there is/are no such regulation(s).

I'm happy enough with the position that not knowing that there aren't is incompatible with assuring people that there aren't.

Until Winston does KNOW that there are not I will continue to tell him that he MUST NOT tell people that there are not.

 

[hard-work]

A switched FCU needs to be at the combi. Have a 6A mcb at the consumer unit for the combi. Then have the right sized fuse in the FCU stated by the makers of the combi. The switch in the kitchen I would keep, or at least leave the provision, to switch the combi on and off via the thermostat circuit. This could override the wireless timer, a permanent on-off for heating.

 

[EFLImpudence]

A branch off a circuit is a "spur".

The thing with a fuse in is a (Switched) Fused Connection Unit.