fuses getting hot....

[arctic]

hi i've just fitted a shower at my girlfriends flat, and it's a 10.8kw unit, the old one was a 7kw so i've changed the fuse in the consumer unit (an old wylex one) for a 45amp fuse with a trip switch.

is 45amps too much for the old wylex unit?
the fuse gets warm when the shower is being used, and i don't know if it should.

the cable is big fat twin and earth, so i'm just a bit worried that the fuse is getting hot.

thanks in advance

 

[another_sparky]

how far is the run from the CU to the shower? and is
is the cable 10mm? or 6mm?

 

[arctic]

its no more than 4 metres, probably really only 2.

its the same size as the cooker, where does the 10mm come from, what is it a measure of? the cable is about 13mm wide and 5mm thick.

thanks

 

[XP]

No offence intended Arctic but I suggest that you get a proper sparks to check your new shower installation. You might very well end up with an ex-girlfriend as a result of fire/electrocution. Do not use the shower until it is checked. Be SAFE not SORRY.

 

[arctic]

thanks, a general builder friend said the shower installation was fine but he didn't know about the old wylex boards.

 

[XP]

"General Builders" are excellent source of general advice but you need specific electrical advice to BS 7671. It is very likely that your "big fat T & E" is only 6mm as it previously fed only a 7kW shower. It will not feed a 10.8kW shower. If its 10mm it might be a loose terminal connection on the CU. My last post still stands.

 

[securespark]

Have had this out with my friend round the corner at Wylex in Manchester.

He says if the consumer unit has only a 60A main switch then it cannot be used to run a high powered shower. Main switch needs to be 100A

AND don't forget that every cu manufacturer recommends only one MCB in excess of 32A be fitted to any one board.

If you want to speak to the technical chap, ring 0161 998 5454 (Wylex) and ask for Ian Kenworthy. He's very helpful, but think he's only there on Tuesdays and Thursdays.

 

[ban-all-sheds]

....he's only there on Tuesdays and Thursdays.

It is an ancient sparky
He worketh one of three
The other days he stayeth in bed
Too drunk to stand or see

With apologies to S.T Coleridge

 

[securespark]

Ian or me, BAN???????

 

[ban-all-sheds]

If the cap fits.....

 

[arctic]

ok thanks for all the advice.

going to get a sparks to change the consumer board and check the cable to the shower.

any idea what sort of cost a new consumer unit should be? (just the fitting) its a small 2 bed one level flat.

thanks again