Electrical question

[Jon W]

Hi all

I want to install a 3Kw Elecro heater in my growing on pond (thought I'd make my own personal recession even worse!) and I don't understand what I need to do in terms of ensuring that I have an adequate power supply.

I've got a power supply going into my shed from the consumer unit in the house. There is a trip switch in the shed and there is another spur leading from there to a wooden shed in the garden which feeds my main pond.

My questions are as follows;

Should I have a completely separate electrical supply going from the house to feed the heater?

Would I need to upgrade the consumer unit in the house to cope with the extra 3Kw load and how do I tell from looking at it whether this is the case?

All the switch boxes I've seen for controlling supply to pumps, UV's, etc seem to have a max rating of 3Kw. Is there one which could cope with a higher rating so that I could control everything off one panel?

Please note I will get a proper sparky in to do the job, I just want to get a rough idea of what needs to be done before discussing the job with anyone.

Yours in utter confusion.

Jon

[herbie]

Jon

On my Pond I used to have a 3Kw heater
I've got no fish in the pond anymore since
the pump pack up whilst I was at Work (That was in May)
so I didn't know till the next morning when I looked out
of the upstairs window & saw there was no air in the pond.
I replaced the pump when I came home from work (But it was
to late buy then) Then fish seemed OK at the weekend. When I
went out the back to have a good look in the pond.

My heater was wired in to a standard 13amp fused spur off of
my old switch box that was beside the filters under the decking
cover behond the brick out house thats behind my house

Regards

[koicarpus]

Hi Jon,

It's hard to say anything about your installation without actually seeing it.

You may need to upgrade/install an R.C.d or R.C.B.O. in your house which is supplying your shed D.B.

The cable feeding your shed D.B. may need to be replaced (increase in size, or swa )

Your shed D.B. may not be suitable, or come to think of it nothing may be suitable, it's hard to say without looking.

Get a few qoutes, don't cut corners, make sure they are registered with a governing body, NIC for example.

Where are you based ??

Kind Regards

Dave (sparky)

[Jon W]

Hi Herbie

I'm a bit nervous about taking it off the existing box. I can't tell what rating anything has so I'm think that I'll probably have to rewire.

Hi Dave

I'm based out on the West Wales coast (Carmarthenshire) so a bit off the beaten track. All specs on the various boxes refer to amps but not wattage hence the confusion. I think you're probably right and most of the wiring and boxes will need upgrading.
Reason I wanted to get some input from the site is that I've had a couple of bad experiences when having someone look at the electrics and wanted to have a bit of background info before asking anyone to quote.

Cheers

Jon

[shaun18]

Hi Jon
If it helps I run my 3kW heater on a seperate 2.5mm armoured cable wired directly to consumer unit on a 16A RCD protected MCB. 3kW heater @ 240 V is very nearly pulling 13 A and @230V is slightly over. I say this as some 3KW heater manufacturers say they can be run on a 13A plug (usually melts if cheap type, or so I have been told)

Shaun

[longboardpete]

Don't forget you will have other bits and pieces running as well as heater, you also have to take into account lenght of cable run due to volt drop and load. Can i also just remind you that unless you have a part P certificate you can not undertake this work as it would need a certificate issued at the completion of works. Best to just get a few quotes from a member of the NIC or the likes (stay with NIC) as mentioned earlier

To work out loading you Divide the power (watts) by Voltage I = P / V so 3000 watts / 240 volts = 12.5 amps, this will give you some idear of your total loading

[Jon W]

Hi Shaun and Pete

Thanks very much for the info. That was exactly what I needed so that I can discuss the issue with an electrician. I have absolutely no intention of doing the work myself - I'll have a go at almost any DIY job except electrics and anything that involves heights!

Thanks very much.

Jon