Feed to outside oil boiler.

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The boiler spec asks for a proper protected outside electric supply. I take it the house ring will suffice with a cct breaker socket and plug. Will it be OK to make use of an existing socket and run a cable through the wall to the boiler or does the isolation switch need to be outside. Note the boiler has its own power switch on the front panel. Thanks.
 
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:confused:

Boiler will require a 'call for heat' control voltage (often a switched Live from the controls) as well as, possibly, a permanent Live. Plus Neutral and Earth of course.

That may require 3 poles of isolation? Possibly four if a Combi?

IF the external isolator switch is for maintenance safety reasons, a weatherproof rotary isolator would be the go to device (and allow for 'locking off' if desired).

Perhaps this requirement needs discussion with / direction from the boiler installer?
Or someone with external oil boiler knowledge to get clarification?

I have to say that my in garage oil boiler has no isolator near it... and the mains supply for the heating controls inc the boiler is in the airing cupboard (a simple FCU).
 
That may require 3 poles of isolation? Possibly four if a Combi?
All controls are connected to the same supply. If there are external controls that require hard wiring, the supply is taken from the boiler.
A standard FCU is all that's required. Same for any other heating boiler.
 
In the commercial environment I've only ever known any outdoor oil burning apparatus be fed via an isolating transformer and local TT arrangement. I have no idea if it's any sort of regulation or a consultants spec.

Having never worked on a similar domestic situation I have no idea if the same thing is done/required.
 
All controls are connected to the same supply. If there are external controls that require hard wiring, the supply is taken from the boiler.
A standard FCU is all that's required. Same for any other heating boiler.
Not always the case. In the controls industry we have to jump through all sorts of hoops to overcome multiple sources.
For a remote boiler I'd expect to install an isolator at the boiler independently of the remainder of the system.
 
All controls are connected to the same supply. If there are external controls that require hard wiring, the supply is taken from the boiler.
A standard FCU is all that's required. Same for any other heating boiler.
Certainly not how it's been done in my home. Nor in any other home I've owned in fact. Mains to the controls-timers then to wiring centre and from there to the boiler, pumps, motorised valves etc.,. {Mind, I don't believe any boilers I have had needed a permanent Live feed just a 'call for heat'.}

I'm not saying your way is not the correct way; but it is a discussion that needs to be had with the installer rather than an assumption made on a (near) anonymous internet forum. Especially for maintenance safety. {We don't know if this is a brand new install in a new dwelling or a replacement / relocation on an existing heating system with existing controls and wiring.}
 
Certainly not how it's been done in my home. Nor in any other home I've owned in fact.
Ok.

Mains to the controls-timers then to wiring centre and from there to the boiler, pumps, motorised valves etc.,.
I don't think you have that correct - unless wired by an idiot.

{Mind, I don't believe any boilers I have had needed a permanent Live feed just a 'call for heat'.}
Some (most?) of them do; some have timers and pump overrun etc.

I'm not saying your way is not the correct way; but it is a discussion that needs to be had with the installer rather than an assumption made on a (near) anonymous internet forum. Especially for maintenance safety. {We don't know if this is a brand new install in a new dwelling or a replacement / relocation on an existing heating system with existing controls and wiring.}
Op has asked on the internet. Feel free to help and ask the OP any questions you think relevant.
 
Certainly not how it's been done in my home. Nor in any other home I've owned in fact.
You say that, but ....
Mains to the controls-timers then to wiring centre and from there to the boiler, pumps, motorised valves etc.,.
As EFLi has said, that does sound a rather odd order but, even if it were correct, it sounds as if you are describing a situation in which (as flameport said), everything to do with the heating system (controls/timers, wiring centre, boiler, pumps & MVs etc.) does have the same electricity supply, aren't you?

When flameport (and others) have talked about 'the boiler supply', they are 'talking electrically' (i.e. indicating that all the components of the CH system have a common supply), not necessarily indicating the order in which the various parts of the heating system are connected together.
{Mind, I don't believe any boilers I have had needed a permanent Live feed just a 'call for heat'.}
That would be true of my ancient boiler. However, I think that nearly all boilers have, for quite a long time ,required a permanent live, as EFLI has said to provide an over-run for the fan (after the 'call for heat' goes away), and quite possibly other things as well.

Kind Regards, John
 
I have worked on a number of 'domestic' systems, if I had to put a figure on it I'd probably say around 100-200. So not as many as pet pants who install them on a daily basis but enough to get an opinion.
I find the vast majority of NON COMBI systems are wired:
Mains to the controls-timers then to wiring centre and from there to the boiler, pumps, motorised valves etc.
Or possibly; Mains to the wiring centre and from there to the controls-timers, boiler, pumps, motorised valves etc.

From a random boiler installation instruction manual
1692806980933.png
 
I might have been a bit harsh as perhaps Rodders' description was not entirely accurate, but

surely only your second example constitutes a 'wiring centre'.
 

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