Shower Mystery

[danielbb]

I want to install a shower (45amp)

The previous occupants of my house had a shower, the wire is there and also the switch, which now has a blank cover. I checked and there are two thick grey wires inside the switch housing. In the fuse box downstairs all the trip switches are taken with a few spare blank spaces. (see diagram, wiring and components in red boxs are prensent.)

I am trying to discover how it was wired previosly. Is there a hidden MCB? (blue box) I have had a quick look up the loft and i can't see one. Maybe there an extra 45 amp trip switch at one point?

i)How would a electrician diagnose whats what?
ii)If there is a MCB can i check at the cosumer unit for evidence of it?

All work we either be done or tested by a qualified technician before i use the shower, i am not about the risk mine or anyone elses safety with the help you give.

Thanks.

PS. there looks like theres a cable that has been put in that goes straight down into the consumer unit. I can tell due to the bad plastering.

 

[Adam_151]

I guess the cable will be taped up in the CU, either that, or someone has cut the fed and taken the cable to feed the cooker instead

can we have a picture of your cu with the cover off?

 

[danielbb]

Yeah i can get a photo of it tommorow. I suppose it could even of been done without any fuse/switced fuse at all! ?

Ill take the cover off tomorrow and take a picture.

 

[Adam_151]

Yeah i can get a photo of it tommorow. I suppose it could even of been done without any fuse/switced fuse at all! ?

Ill take the cover off tomorrow and take a picture.

Yes, keep your fingers out of it, or if you are worried, switch the main switch on the CU off, then its just the incomming tails to the switch that are live

 

[danielbb]

Yep im going to turn it off and keep away from the end isolating switch.

 

[danielbb]

All accurate. that top let channel must be it, lines up with the bad plastering too. could that 100amp isolator be a problem? theres 80a in switches now.

What to do from here?, where would an mcb run from exactly?
That spare metal joiner block could be handy?

Cheers

 

[ban-all-sheds]

I want to install a shower (45amp)

The previous occupants of my house had a shower, the wire is there

But what size is it?

i)How would a electrician diagnose whats what?

By visual inspection, and tests to verify the presence and condition of a circuit to the shower.

ii)If there is a MCB can i check at the cosumer unit for evidence of it?

That's the likeliest place to find an MCB....

What to do from here?,

Call an electrician...

where would an mcb run from exactly?

What's wrong with putting one in the CU?

That spare metal joiner block could be handy?

¿Que?

 

[danielbb]

I said i was calling an electrician. I want to learn how to do this, im not dangerous. I am enrolling on a course to learn electrics after i have finished my mcsa courses. I know i dont know the terminology yet, i will when i turn my attention to it, im studyng something else at the moment, hence im asking on here.

I cant remember the name for the strips of metal with screws in to join wires. where does the input to the mcb come from? the isolater output i guess?

Cheers.

 

[danielbb]

The shower instructions recommend a 45amp rated wire. 9.5kw shower i think, i can check if you wish.

 

[danielbb]

And whats wrong with sheds

 

[ban-all-sheds]

I cant remember the name for the strips of metal with screws in to join wires.

Depends on what type they are, where they are, and what they are used for. I just wondered what you meant by a "spare metal joiner block", and where it was, and what it was used for, and what you thought it might be handy for...

where does the input to the mcb come from? the isolater output i guess?

Yes - they are all supplied from the busbar in the CU.

The shower instructions recommend a 45amp rated wire. 9.5kw shower i think, i can check if you wish.

That's fine for that shower, but if you want to use the existing cable, the question is what size is it?

And whats wrong with sheds

I mean

NOT

 

[danielbb]

If that was done the total load throught the isolator would be 125a when everythings on ? if it is, is that a problem, bare with me if im way out.

cheers

 

[danielbb]

Why dont you like them retailers? what do you use? why do you call them sheds?

 

[danielbb]

I found this on a website.


Maximum Supply Fuse and/or CU Isolator rating
Common Circuits

Example only. Not definitive.
Recommended

Maximum Shower Rating's
____________________________________
40A
1 Ring Main, 1 or 2 Lights, 1 Boiler
Not Recommended
____________________________________
60A
2 Ring Mains. 2 Lights. 1 Boiler
7kW
_____________________________________
80A
1 Cooker. 2 Ring Mains. 2 Lights. 1 Boiler
9.5kW
______________________________________
100A
1 Cooker. 2 Ring Mains. 2 Lights. 1 Boiler
11kW
_____________________________________

My max recommended is 11kw then, so thats good news. Ill check cable ratings next.

 

[danielbb]

So im guessing thisis the solution?
These mcb's standard size?

Cheers