13a Hot tub power supply

[smith69085]

Strangely, I have recently inherited a hot tub! Not something many people can say and have been looking at power supplies.

All the info I can find relates to much larger tubs with 4-6KW heaters and multiple pumps. In which case 6mm swa cable and all the relevant protection / isolators which is fair enough.

However the tub I have is a plug and play type, with a three pin plug. Think of a lazy Spa, but with a wood frame. The heater is only 2KW, and the 2 speed pump is not huge and will only run the heat when on low speed. When on full speed the heat turns off.
I don't like the idea of just plugging this into an outside socket though, a hot tub on and extension lead seems like a terrible idea, and ridiculous if its legal!. Its not going to move so want to wire it in but a 32a supply seems overkill.

What I want to do is wire the tub into a wall isolator a few meters from the tub, as it should be Using the supplied hot tub cable.
Then run from the isolator to the house (clipped along a high wall) using swa (around 10m) to another junction box
Which feeds through into the house for connecting up using non armoured cable for ease. I need to have my consumer unit replaced so will get the sparky to do all the finishing up at the same time.

Question is, will the above be all ok and which thickness of cable / isolator should I use? I guessed around 20amp to allow some head room. Everything on-line screams 6mm and 32a minimum, but this thing is less powerful than a kettle?

Also, is swa the thing to use, or would sy cable be ok as it will be clipped up high to make life easier?

 

[PrenticeBoyofDerry]

If the hot tub came with a factory fitted plug? I don't see why you/your electrician cannot run a 16A radial circuit from the CU. It is wise to use SWA on the external routing. At a distance of 10m, 2.5mm CSA, should be more than enough.
Do to the nature of this appliance RCD protection should be used.

 

[ban-all-sheds]

Everything on-line screams 6mm and 32a minimum,

Because that's what real hot-tubs need.

but this thing is less powerful than a kettle?

That's because it's not a real hot-tub.

will get the sparky to do all the finishing up at the same time.

You can't present an electrician with a part-completed fait accompli and ask him to "finish up" and then certify on official documentation that he sis all of it.

You need the electrician to do all of it - and that includes deciding on the type of cable, the route it takes, etc. But before you spend any money, time or effort in installing it and providing a connection for it, do the sums on how long it's going to take a 2kW heater to get the water up to temperature.

Chances are you'll decide it's a useless item, and not worth any further investment.

 

[bernardgreen]

Any thoughts about exporting a PME ( TN-C-S ) "earth" out to a tub of water that is outside the equipotential zone of the building. As with double insulated power tools in the garden exporting a PME "earth" to metal work in the garden is frowned upon.