can i install my new electric shower on my old cooker curcuit cable(6MM).I
now have gas hob with 13amp plug in to the mains oven.shower is 8.4Kw,

thanks for any advise GM

then do it with a dedicated 45 Amp Double Pole Switch in the
kitchen and use it as the maintenance isolator, that way you
won't need to fit any more switches into the circuit.

Only if it has holes to fit a padlock in the off position.

Also, make sure you fit a 30 Amp rewireable fuse or a 32 Amp
type B Miniature Circuit Breaker in the Main Consumer Unit.

These will allow between 7.2kW and 7.7kW, if we are generous and allow 240V
for our calculations. The shower is 8.4kW. I'd go with a 40A/30mA Type B
RCBO. The thought of having an instananeous shower on a rewirable fuse with
no RCD makes my spine shudder (and will probably make your's shudder pretty
uncontrollably in the event of an earth fault).

I haven't got the tables in front to check the cable's suitability. 6mm
seems marginal and certainly needs to be calculated properly to be sure it
is suitable.

Christian.

"Christian McArdle" wrote in message
. net...
then do it with a dedicated 45 Amp Double Pole Switch in the
kitchen and use it as the maintenance isolator, that way you
won't need to fit any more switches into the circuit.

Only if it has holes to fit a padlock in the off position.

Also, make sure you fit a 30 Amp rewireable fuse or a 32 Amp
type B Miniature Circuit Breaker in the Main Consumer Unit.

These will allow between 7.2kW and 7.7kW, if we are generous and allow
240V
for our calculations. The shower is 8.4kW. I'd go with a 40A/30mA Type B
RCBO. The thought of having an instananeous shower on a rewirable fuse
with
no RCD makes my spine shudder (and will probably make your's shudder
pretty
uncontrollably in the event of an earth fault).

I haven't got the tables in front to check the cable's suitability. 6mm
seems marginal and certainly needs to be calculated properly to be sure it
is suitable.

Christian.



My apologies. Thank you Christian. I did mean a 40 Amp type B MCB, but my
mind was on another job where the situation called for a 32 Amp MCB.

Old age doesn't come itself, Eh ? :-))


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"Christian McArdle" wrote in message .net...
These will allow between 7.2kW and 7.7kW, if we are generous and allow 240V
for our calculations. The shower is 8.4kW. I'd go with a 40A/30mA Type B
RCBO. The thought of having an instananeous shower on a rewirable fuse with
no RCD makes my spine shudder (and will probably make your's shudder pretty
uncontrollably in the event of an earth fault).

I haven't got the tables in front to check the cable's suitability. 6mm
seems marginal and certainly needs to be calculated properly to be sure it
is suitable.

Bearing in mind the duty cycle of an electric shower, wouldn't the
overloading be tolerable, in practice? I know of at least one
installation with an 8.5 kW shower on a 32A breaker.

If the OP is using a former cooker circuit, he might be well advised
to move it to the RCD protected side of his CU.

Also, he isn't running his new oven from the 13A outlet on the cooker
switch, is he?

Bearing in mind the duty cycle of an electric shower, wouldn't
the overloading be tolerable, in practice? I know of at least
one installation with an 8.5 kW shower on a 32A breaker.

I'd be amazed if it didn't work, I have to say. I don't have the curves in
front of me, but suspect a 10% overload would take tens of minutes to blow,
if ever. It would still be very bad practice, though.

Christian.

"Christian McArdle" wrote in message
. net...
Bearing in mind the duty cycle of an electric shower, wouldn't
the overloading be tolerable, in practice? I know of at least
one installation with an 8.5 kW shower on a 32A breaker.

I'd be amazed if it didn't work, I have to say. I don't have the curves in
front of me, but suspect a 10% overload would take tens of minutes to
blow,
if ever. It would still be very bad practice, though.

Christian.


I agree it would probably work but it's the kind of practice reserved for
qualified sparkies houses - you know like decorators houses always need
painting and plumbers houses still have lead piping etc. etc. ;-)
Richard