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Hi all, I am new here, and a DIYer, so please be gentle.

I recently bought an Intex portable hottub. One of the inflatable ones like the Lay-Z-Spa units. The unit claims it is only pulling 2400w and comes with a pre-fitted 13a socket with an inline RCD, and I confirmed this with an inline power meter.

I had previously installed a IP rated external power socket in the garden for external devices, and as it has 2x13a sockets this seemd like it would be fine. After an hour or so of the hottub in heating mode the socket was very hot, so i unplugged it and let it cool down. I then replugged it in a few hours later, and after maybe an hour it was hot enough to be making a smell. I unplugged it and investigated, it had melted the inside of the socket.

In this instance it may have been poor installation on my part, looking at the area around the melting it looks like it may have been arcing so thats likely what caused the melting. It seems like the screws were loose. Lesson learned, crisis averted.

But yeh, not ideal.

Anyway. In an effort to eliminate my potential poor workmanship from the equation I relocated the tub to power off of a professionally installed regular socket inside the house. However after doing this, this socket started to get hot too. After running the hot tub for about an hour the cable, plug, and socket, are all hot to the touch. Although not melting this time, but certainly so hot as to cause concern.

So, my question is, should these units get this hot under normal conditions?

My understanding is that hot cables = problems, but I dont see how I can do anything that would resolve this as a normal consumer. The device comes with a 13a plug suggesting that it should be fine to just plug into a regular 13a socket.

The only solution I can think of is removing the factory fitted plug/cable, and hard wiring in a higher rated 16a+ feed (either using a 16a commando plug or just a dedicated feed direct from the consumer unit) which would ideally be done by a qualified electrican. But theres no indication that this is a requirement on the box. I could understand this being a requirement of a bespoke fixed hottub installation as they are usually bigger, and more powerful anyway, but these units should essentially work like a regular consumer device.

Sorry for the wall of text, and again, be gentle :)
 
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telectrix

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should be fine on a 13A plug. the usual cause of overheating is poor contact between the plug pins and the socket. generally due to cheap sockets. the tub pulls 10A when heating, which is well within the capabilities of a BS1363 socket. having said that, there is guidance in the regs. that loads of that size would be preferable on a dedicated circuit. your suggestion of such with a commando socket and plug is good,but first, I'd fit (or get fitted) a good quality outside socket ...BG are what I fit... and ensure that the plug pins are clean.
 

telectrix

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Could've been a loose connection inside the plug top or just a cheap and nasty plug top
shouldn'tbe.factory fitted plugs are usually good quality. but could be a manufacturing fault. hot tub cable is qiute thick. it's 1.5mm but with the thicker sheath, looks more like 2.5mm. had same problem, but was own fault. plugged it into a cheapo extension lead as a temp. "see if it works OK" prior to fitting a IP rated socket close to tub.
 

mattg4321

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I agree, they are usually good. But not always. As Midwest says though, it shouldve been replaced after the first time it overheated.

Think the flex was 1.5 3C H07 when I've seen them so that shouldn't be an issue at all.
 

UNG

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Moulded 13A plug top by any chance, that would be the first thing to get rid of and replace it with a 13A plug or a 16A commando plug and socket.
Over the years since they were introduced I have seen very few fitted to high load appliances that have not caused damage to sockets and / or the plug top
 

UNG

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shouldn'tbe.factory fitted plugs are usually good quality. but could be a manufacturing fault.
By fitted do you mean the moulded type plug top
I've always been suspicious of the moulded plugs since the 80's when a HTM came out recommending they were replaced in all NHS premises as some were found to have strands of wire visible in the moulding, although I can't remember if there were any reports of shocks
 

FatAlan

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Out of interest, what is a good solid make of BS1363 plug? Some of the ones I’ve purchased recently have looked a bit naff (cheap and nasty) :)
 

telectrix

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these are pretty well bomb proof.
 
D

Deleted member 26818

Out of interest, what is a good solid make of BS1363 plug? Some of the ones I’ve purchased recently have looked a bit naff (cheap and nasty) :)
MK, Duraplug or any from Woolworths.
 

telectrix

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woolworths??? who's zat?
 

ackbarthestar

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A hot tub getting hot ? .... umm, interesting.
As others have stated, a good quality moulded plug would suggest loose terminal connections in the socket or/and a weak plug-socket fitting.
 
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Thanks all for the replies. The plug, which is molded to the cable, looks in perfect external condition so i dont think its a fault there, i think its likely just high constant load. It just surprised me that it would get that warm. I will look at upgrading the cable / getting a dedicated feed put in at some point to reduce load on the main ring, but for now i will just make sure not to leave it running unattended.
 

Midwest

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Thanks all for the replies. The plug, which is molded to the cable, looks in perfect external condition so i dont think its a fault there, i think its likely just high constant load. It just surprised me that it would get that warm. I will look at upgrading the cable / getting a dedicated feed put in at some point to reduce load on the main ring, but for now i will just make sure not to leave it running unattended.
When thermal decomposition occurs, such as with loose terminal connections, all the associated terminals, connectors & pins will be effected, Are you sure your manufacturers plug (top) is not 'dirty'?
 
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