Hot tub electrics - advice needed

SneakAttaack

I’m installing a outdoor socket to power my inflatable hot tub using this kit from B&Q (sorry, can’t post links):

Diall 13A 2 gang Grey Switched RCD socket

Does this seem suitable for powering the hot tub?

Also, the cable that goes from the junction box to the RCD is too short so I’d like to replace it with longer cable but not sure what to buy. It says on the cable “H07RN-F 3G 1.5mm2”. Any pointers please?

Just to note, I plan to get this checked out by a qualified electrician before using it with the hot tub.

Thanks

rob7475

I think all inflatable hot tubs run from a standard 3 pin plug. As long as your socket is wired in 2.5mm T+E you should be good to go. However, if it's on a circuit shared with other appliances, make sure there's enough spare capacity in the circuit to take the extra usage.If you're on a radial circuit rather than a ring main, it won't take much to trip the breaker.

Also, you may not need an RCD socket as most inflatable should be fitted with an RCD device from the factory.

grumbler

It's suitable for any appliance with 13A plug.

However, I don't understand the purpose of the grey junction box, i.e. why the plug with RCD isn't corrected to the outdoor socket directly.

Neither do I understand what they want £50(!) for.  A similar set with a single socket is just £14 at TradePoint (the same BNQ)

The RCD plug is £9 at Screwfix, and the double socket is just about a tenner there. Or you can buy a double socket with RCD for £23

That said, if all sockets in your house are already RED-protected you don't need an extra RCD.

fenwick458

No that kit you have posted from B&Q does not seem suitable in fact it seems like the worst possible idea for a hot tub.  it's just an extension lead in theory, the hot tub will use 13A Which is the maximum a plug is designed for, you really want as few joints as possible, not socket in house - plug in RCD - junction box - outdoor socket - hot tub plug. 
you only really need one RCD, most hot tubs have them built into the flex so if your has that, just get a normal IP double socket fitted back to back with one of the existing socket in your house now,  such as this https://www.discount-electrical.co.uk/product.php/390065784/bg-electrical-wp22-nexus-storm-grey-2-gang-double-pole-switchsocket-ip66-13a
or this https://www.discount-electrical.co.uk/product.php/397503935/click-oa036ag-aquip-grey-polycarbonate-2-gang-weatherproof-switchsocket-ip66-13a-230v-width--158mm-x-height--155mm-x-depth--95mm
the advantage those sockets have is the double socket part is the same that goes in your house inside and you can replace that part for £3 if you burn the socket out, which is quite likely.
also heres a link to some cable
https://www.discount-electrical.co.uk/product.php/7037/h07-3c-1-5bl-h07rn-f-black-3-core-circular-rubber-insulated---polychlorophene-sheathed-oil-resistant---flame-retardent-flexible-cable-1-5mm---priced-per-metre-