is 6mm cable ok for 8.5kw shower

[flyfto]

hi is 6mm ok for an 8.5kw shower?

shower went bang last night, looking to just replace exisintg 7oddkwatt shower, with new 8.5kw shower, but exisiting cable is 6mm is this ok for the above

cheers

 

[Cremeegg]

Need to know rather more information - like length of cable run; cable route - through any insualtion etc.

Personally I'd go for as big as possible say 9.5kW - then you can get a decent amount of hot water out of the shower.

 

[flyfto]

length of run = bout 10m max, through loft down into bathrooom,
shower going into my flat which i let out so not bothered bout 9.5kw.

just wanna confirm that 6mm cable will be ok to use with 8.5kw shower !!!!!!

 

[Cremeegg]

6mm cable will take depending on its installation method between 32 & 46A - your shower is 35A - so if you give us more information on amount of insulation and the way the cable is fixed we can tell you whether its OK or not.

 

[andywatson]

I asked a similar question a while ago for exactly the same rating of shower. Someone poined me in the direction of a website that calculated what you needed. I seem to remember that 6mm2 was really really borderline. Since you are running it rough the loft I guess it will be sat on insulation (not good) and also underneath the plaster/tiles in the bathroom- again, not good.

I remember deciding it wasn't enough, and replaced it with 10mm2 to be on the safe side.