Installing a modern hot tub is relatively straightforward, but that’s not to say there aren’t a few considerations you’ll need to make before firing one up! One question we’re often asked is what electrical requirements do I need to run my hot tub?
A lot of the standard tech inside hot tubs has changed and improved during the 10+ years we’ve been running this site. However, the electrical requirements needed to run a hot tub power supply safely have (for the most part) remained the same.
Hot Tub Power Requirements
Hard-shelled hot tubs generally use a 32A hard-wired power supply. This means the hot tub’s power cable must be hard-wired on its own fused spur directly into your home’s mains electrical system and cannot share a power supply with any other electrical appliances.
A 32A hot tub can’t be plugged into a standard 3-pin plug socket, so you’ll need a professional electrician to install a dedicated outlet protected by a mains circuit breaker (MCB). This circuit should be designed to cover the max amperage of the spa (32A) + 25% to account for the initial rush of current when the hot tub is first powered on.
You’ll also need an IP65 Rotary Isolator Switch installed to safely cut the power supply during maintenance or in an emergency. This switch should be at least 2m away from the hot tub and run into a 6mm² 3-core SWA cable that leads to your spa’s pump unit.
Inflatable Hot Tub Power Requirements
Inflatable hot tubs mostly rely on 13A power supplies. These lower amperage systems are popular as they’re less expensive to run and easier to install than 32A supplies. To safely use a 13A system, you’ll need a waterproof outdoor 3-pin plug socket with a built-in RCD unit.
This socket must be installed at least 2m away from your hot tub to avoid the risk of any water coming into contact with the live current. Choosing a socket with a sealable cover is also a good idea, as this will protect the device from water splashes and being tampered with.
Why an RCD is Essential
An RCD (residual current device) is essential as it will automatically switch off your electrical circuit in the event of a dangerous fault. This means if somebody touches a live wire or there is an electrical surge in your power supply, the current will cut out before it can do any harm.
Can you plug a hot tub into a standard socket?
Whilst a hot tub using a 13A power supply can be plugged into a normal socket, you shouldn’t use one when running your hot tub. To safely power a spa, you must use a waterproof socket with a built-in RCD unit to adequately protect yourself from electrical shocks and faults.
Can any electrician wire a hot tub?
Any home electric supply adjustment must comply with Part P of the UK’s Building Regulations. This means only a professional electrician registered with a government-approved Part P scheme can legally wire a hot tub to your mains electrical system.
What if the spa plug becomes hot?
If your spa’s plug is hot to the touch, you should immediately switch off your pump and unplug the device from the socket. The most likely cause of this issue is that your hot tub is drawing a larger current than the circuit is designed for, resulting in frictional heating of the cable’s wires.
You’ll need to hire a professional electrician to come and look at your setup before plugging your hot tub back in, as you’ll likely need to have a more suitable socket installed.
That just about covers the electrical requirements needed to run a hot tub safely. You’ll first need to determine whether your spa has a 32A or a 13A power supply. For a 13A system, you may already have a suitable outdoor socket, but it’s still wise to consult a professional to ensure your circuit won’t overheat!
32A systems require a government-approved electrician to wire your hot tub to your mains electricity supply safely. And, remember that for either scenario, your socket will need to be at least 2m away from where you intend to install your spa. With these bases covered, you’re all set to safely enjoy your hot tub!