Garden office electrics

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I've a garden office (just bought house) which has the following:

  1. 3x1500w panel heaters each with own mcb and 2.5mm cable and each having their own 16A breaker.
  2. 1 x mains ring which had one run badly eaten by mice causing the rcd to drop as soon as ring was made live.
  3. No more space in DB board.

I located and fixed the broken ring section by running a new 2.5mm t&e. I also took the opportunity to install 3 additional sockets in the ring.
Anything wrong with what I've done?

I'd like to install a new ring to power some servers (nothing big, just want to have dedicated circuit for them). Can I join two of the heaters together at the breaker - now totalling 12A, and use the now-free space for a new 32A mcb and new ring?

I can't see that it is a problem. I'm unsure why they'd have separate breakers for each heater.

Thanks and merry Christmas!
 
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Does the office actually need three heaters? We have a garden room and only plug in a Dimplex Ceramic 2.5 kW fan heater and only use it on the lower setting as the room is quite well insulated. Why do you require a ring for servers? Wouldn't a radial circuit be adequate?
 
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You don't need a 32amp ring for a few servers though.

What about using one of the heater circuits to feed the server sockets, using the original 16amp breaker.

And re-feed the heater by spurring off the existing ring circuit.

?

Just an idea.

But as indicated earlier, you really need to check how the garden office is fed from the house, as doing this work may prove to be pointless...
 
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thanks for the replies.

You're correct - I could just add a single radial using the 16A breaker for the servers. They are directly below the CU so short run of 2.5 would suffice(?).

Do I _need_ 3 heaters? Dunno - they already there ;)

Given what I have done - adding in two extra sockets onto the ring and replace a faulty section of cable with 2.5 twin and earth - do I need to update anything in certification?

The feed to the office looks like it's 6mm run from garage where it comes off another CU.
House CU -> Garage CU -> Office CU all-in around 50-60m I would expect.
 
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The feed to the office looks like it's 6mm run from garage where it comes off another CU.
House CU -> Garage CU -> Office CU all-in around 50-60m I would expect.
Yes, but what size fuse or MCB does it come from?
 
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It's actually only a 32A breaker feeding office. Just noticed that.
Not exactly a lot of headroom.

So, given the cable looks like 6mm (I will confirm in the morning when it's light). I could increase that to a 63A?
Cable is armoured, pinned along inside wall of wooden garage, through wall, buried in soil, up side of office.

The garage is in turn protected by 40A breaker so again, not much to go on. OK to upgrade both?
 
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. I could increase that to a 63A?
No.
6mm² max 40A, possibly 45A if such a device is available, and depending on installation method.
Voltage drop over a 60m length will be a problem long before you get to that.

Not likely you would actually need such a large capacity anyway, 3x 1500W heaters seems excessive.
 
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It's actually only a 32A breaker feeding office. Just noticed that.
Not exactly a lot of headroom.

So, given the cable looks like 6mm (I will confirm in the morning when it's light). I could increase that to a 63A?
Cable is armoured, pinned along inside wall of wooden garage, through wall, buried in soil, up side of office.

The garage is in turn protected by 40A breaker so again, not much to go on. OK to upgrade both?
I'd carefully check cable size and run length before you go throwing wild numbers at the job- at 60m, 32A is about right for 6mm.
 
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The garage is in turn protected by 40A breaker so again, not much to go on. OK to upgrade both?
I doubt that device is providing any over-current protection. Is it a main switch, or an RCD?

on that subject, where is the RCD protection located for this lot?
 
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Most importantly, you need to stop the mice from getting in again.
 
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Interesting. I found a table which said clipped was 65. Nonetheless, it's within reason really.

Heating: I intend removing the heaters. I cannot afford 4.5KW of heating on a daily basis. I've other ideas for heating there; future project.

The CU in the house - feeding this - is a 40A mcb, that feeds the garage CU into a 63A(IIRC) RCD. From there the CU in the office is simply a 100A isolator.
So from an RC point of view, there are two in the circuit
 
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...and - if I remove the heaters I will be just fine, even with the heaters, fully-loaded, I am ok with what I have so I'll leave well alone then :)

@BlueLoo - yes, agreed on the mice. There is now more bait blocks in the cavity than insulation :ROFLMAO::ROFLMAO:
Knowing that this is a problem I will just have to keep on top of it.

Thinking about it some more, the sockets ring is next to the heater circuits and entirely possible they too are damaged..
The heaters have an isolator on each of them - can I disconnect that and put a plug on them? That would remove the risk of the existing cables.
 
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...and - if I remove the heaters I will be just fine, even with the heaters, fully-loaded, I am ok with what I have so I'll leave well alone then :)

@BlueLoo - yes, agreed on the mice. There is now more bait blocks in the cavity than insulation :ROFLMAO::ROFLMAO:
Knowing that this is a problem I will just have to keep on top of it.

Thinking about it some more, the sockets ring is next to the heater circuits and entirely possible they too are damaged..
The heaters have an isolator on each of them - can I disconnect that and put a plug on them? That would remove the risk of the existing cables.

Baiting mice is fine but they don't die on the spot, they go off back to the nest with the food and now you have a nest(s) of dead mice somewhere rotting away.

Do a survey of the unit and try to stop and vermin getting in at all.
You don't want to be using something like your PC after it's been ****ed on by mice, rats, etc....

Traps are better. You see if you have any intrusions and i think they are more humane.

As you say, a full survey of the electrics is inorder.
 
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