A friend of mine is going to replace his shower this coming weekend. The shower he is removing is very old and I believe it is an old 7.2kW Triton. The shower he has got his eyes on is a 10.8kW beast and I have told him that he will need to make several changes electrically. The fuse in the CU will almost cetainly need changing if not then a CU extension may need installing, the wiring between the CU and pull cord switch will need changing to 10mm as the existing is around 20 meters in length and is only 6mm, also the pull cord switch may need changing to 45A. I have also explained part P to him but he still wants to go ahead on his own and without changing anything. Could someone please advise me on what a dangerous and silly mistake he is about to make.
Shower replacement.
- Thread starter zoltron
- Start date
silly mistake
try burning the house down
try burning the house down
If he simply doesn't believe in the laws of physics, what can you do?
So long as he fits the thicker wire and full size MCB/fuse together, or keeps the small fuse/MCB and thin wire and lives with the nuiscence tripping if he showers for long enough for it to warm up (likely 10 minutes plus), I suspect the risk is small.
The only electricaly dangerous thing to do would be to fit a larger fuse or MCB but leave the existing thin wire in place, and then take a long shower.
The only legal risk of part P is if the local authority are informed within 6 months of the work being finshed and decide to pursue him. Both, with respect, unlikley to occur.
(And after 6 months, he can say 'section 127, limitation of time for non-inditable offence' and not be brought to court, just for failing to follow due building regs process, unless it causes a serious injury or death, whereupon the offence becomes inditable, and the time limit is invalid....)
The only electricaly dangerous thing to do would be to fit a larger fuse or MCB but leave the existing thin wire in place, and then take a long shower.
The only legal risk of part P is if the local authority are informed within 6 months of the work being finshed and decide to pursue him. Both, with respect, unlikley to occur.
(And after 6 months, he can say 'section 127, limitation of time for non-inditable offence' and not be brought to court, just for failing to follow due building regs process, unless it causes a serious injury or death, whereupon the offence becomes inditable, and the time limit is invalid....)
Let's not forget that the rating of 6mm² cable when clipped direct exceeds the requirement of a 10.8kW shower....mapj1 said:
I'm not forgetting it. BUT so long as the fuse or MCB protecting it is also too small, the fuse/ MCB thermal part will heat up, as will the wire, and then cut the power off. So long as the breaker or fuse protects the cable, it is silly but not immediately dangerous.
Not the best user experience, to be interrupted part way through a long shower, but an electrically safe one. - very similar to an overloaded socket circuit, or acooker with a tight diversity margin,
-I'm not recommending that, - really the job should be done properly or not at all, just saying that the house won't suddenly burn down overnight , but he will have to be quick in and out of the shower to avoid nuiscence interruptions.
Not the best user experience, to be interrupted part way through a long shower, but an electrically safe one. - very similar to an overloaded socket circuit, or acooker with a tight diversity margin,
-I'm not recommending that, - really the job should be done properly or not at all, just saying that the house won't suddenly burn down overnight , but he will have to be quick in and out of the shower to avoid nuiscence interruptions.
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