MCB for 6kw immersion

Rock12

Hi all,

I am installing my heating and wiring it myself. I have a 6kw element for my tank and wonder if any of you could tell me the MCB size for an element this size and the cable size required to feed it? Thank you.

mizuno12

For the 6Kw unit you need a 32A B Type MCB. Make sure your cable size is correct. You never said the length of cable run from the fuse board to the immersion. minimum cable size here would be a six square cable, possible a 10 square depending on the cable run.

Rock12

Thanks Mizuno! It's about an eight meter run. Would you run the circulating pumps and motorised valves off this MCB or is it dedicated to the element?

brightspark

This sounds like restricted works, unless you are a registered electrician you really shouldn't be doing it yourself.

mizuno12

High Rock12,

The immersion circuit is a dedicated circuit, the pump and valves would be control units and should be wired as control circuits. 8 metres is a short enough run and by calculation you would get away with the six square cable, but I would advise installing the 10 square anyway. Make sure the MCB unit is fitted on the RCD side of the distribution panel or alternatively you could put in a 32A RCBO into the fuse board. Make sure your immersion switch is a 40A pole unit, you can get 25A units but this would be under size and unless you ask the wholesaler for the 40A unit they will give you the standard 25A one.

To clarify Brightspark you don't need to be a registered contractor to perform any alterations in your own home. It is your decision as to employ a contractor or not. Where the works becomes restricted is that you cannot perform these duties for anybody else outside of your own home as you cannot certify the works without been a registered contractor.

It would be worth while asking your own home insurance ( if the property is insured) would they accept these works don't by yourself. Some insurers will accept this as you may well have electrical training, but you are just not a registered contractor. Where this becomes an issue is if there was a accident/fire and the investigators found the fire was caused by electrical means which was a recent installation or incorrect components used they can claim that they were never notified since the policy was taken out of the works done and can use it as a way of not paying out.

At the end of the day if you are unsure of any of the above facts contact a registered electrician, they can certify the works.

2011

mizuno12 wrote: »

To clarify Brightspark you don't need to be a registered contractor to perform any alterations in your own home.

That is incorrect.

Where the works becomes restricted is that you cannot perform these duties for anybody else outside of your own home as you cannot certify the works without been a registered contractor.

Also incorrect.

Since the 1st of October 2013 it is illegal for a non-Registered Electrical Contractor to carry out most electrical work in domestic premises.

It's all here:
http://www.irishstatutebook.ie/pdf/2013/en.si.2013.0264.pdf

This Statutory Instrument does not apply to "minor" electrical works (page 4 of the above document), but the work described by the OP does not fall under the definition of minor works.

Bruthal

2011 wrote: »

That is incorrect.

Well, it is correct in my house.

2011

Bruthal wrote: »

Well, it is correct in my house.

I'm sure it is perfectly executed

However I would not like the OP to be mislead.

Regardless of the lethal position in my opinion this work is beyond the capabilities if the OP.

Bruthal

2011 wrote: »

However I would not like the OP to be mislead.

Regardless of the legal position in my opinion this work is beyond the capabilities if the OP.

Yes true indeed.

Rock12

Thanks again Mizuno that's very helpful! I will proceed with caution.