Wiring up a hot tub

[Cook_90]

Hi guys Iam new to all this so bare with me,

I've been asked to do a barrow job for a friend, wiring up a second hand hot tub for him with a 3kw heater + jets etc.

i planned to run some 6mm twin and earth cable from consumer unit into a rotary isolator outside, then from rotary isolator in 6mm armoured cable to the hot tub.

the consumer unit is quite old and doesn't have any rcd protection just mcbs

the main breaker is 100a and the consumer unit already has 4 x 32a, 1x 16a and 1x6a breakers in but does still have space left on din rail.

would I be right in saying take a supply off main breaker into say 32a rcd?? ( if correct size) then from rcd to 6mm twin and earth??

ive also heared a lot about hot tubs tripping on rcds?
Any help would be great as i generally work in factory's not houses so not up to speed with the household regs etc

thanks

 

[tomspark93]

I'd ditch the t+e and go from the consumer unit in swa as then you don't need rcd protection at the main board. I'd probably then fit a suitable outside mini consumer unit next to the isolator and then go from that to the hot tub in SY cable. This won't offer as much protection as swa but it is easier to terminate and is more flexible.

Unless you you can find an rcbo for the existing board then you'll have to fit another unit either way. If you do it outside you could then easily add some outside lighting around the hot tub at a later date. Depends what the customers plans are in the long run

edit: the outdoor mini consumer unit would house the rcd for the hot tub and anything else that may be ran off it

 

[HandySparks]

Welcome to the forums.

Hi guys Iam new to all this so bare with me,

I've been asked to do a barrow job for a friend, wiring up a second hand hot tub for him with a 3kw heater + jets etc.

i planned to run some 6mm twin and earth cable from consumer unit into a rotary isolator outside, then from rotary isolator in 6mm armoured cable to the hot tub.

Does this mean that part of the T&E run will be outside?

What installation method do you propose to use for this cable inside the house?

What's the existing earthing system?

Where is this proposed work? If in England or Wales, the job will be notifiable.

the consumer unit is quite old and doesn't have any rcd protection just mcbs

the main breaker is 100a and the consumer unit already has 4 x 32a, 1x 16a and 1x6a breakers in but does still have space left on din rail.

would I be right in saying take a supply off main breaker into say 32a rcd?? ( if correct size) then from rcd to 6mm twin and earth??

I very much doubt if the CU has a 100A main breaker. It's much more likely to have a 100A main switch. If you take a supply off the main switch via a 32A RCD, you won't have any overcurrent protection on your circuit.

ive also heared a lot about hot tubs tripping on rcds?

If a circuit to a hot tub is tripping an RCD, there's a fault. I wouldn't install one without an RCD.

Any help would be great as i generally work in factory's not houses so not up to speed with the household regs

BS7671 is the same wherever you're applying it.

 

[telectrix]

if coming off the house CU, you need a 32A MCB in the board, then a RCD alongside. unless the T/E is NOT buried in a wall < 50mm deep, then you can fit the RCD at the hot tub.

 

[soulman]

Why don't you split the tails install a small consumer with rcd & breaker, then swa to the rotary isolator & sy to the tub.

 

[Rockingit]

You lot are making this far harder than it needs to be! If there is space left on the DIN rail then fit an RCBO and feed whatever cable is best - you have to fit an RCD anyway to comply with section 702.

 

[Badged01]

Any help would be great as i generally work in factory's not houses so not up to speed with the household regs etc

Most of your questions have been answered in above posts but just to confirm, apart from conforming to Part 'P' of the building regs for domestic, it doesnt matter whether you work industrial/commercial/domestic we all follow BS7671 regulations for work undertaken! Assuming of course you are an 'electrician'?

 

[davesparks]

Not sure if it's in the regs or in the guidance note but it is recommended that an outdoor hot tub is treated as a swimming pool and an indoor one is treated as a bathroom.

And as far as the suggestion of using SY goes, don't do it, it is not intended for external use and goes manky pretty quickly outside. Use swa if buried or a good tough rubber flex if not.

 

[Engineer54]

What is this hot tub sitting on, bare ground/grass, concrete (patio), wood (patio) or other??
What is the supplies earthing system, TN-S, TNC-S, TT??
What sort of distances are we talking about from the house CU, to the Hot Tub??

You will need an RCD protective device, in fact many Hot Tubs and Jacuzzis will incorporate them in it's control panels. SWA cable should be the cable of choice, and it would be more than prudent to make it a 3 core cable, rather than a 2 core...