Hottub running hot. What to do?

[mrwkuk]

Have you read my #22?

Yes, i have, and in my personal experience, manufs take a dim view of any alterations to any part of the product within the warranty period. This may not be the case with this unit, but going by precident, i expect that it might. Hence my post here.

So out comes the flir camera to look at the flex but not the plug or socket which is clearly where the problem is.

Do you really think I would point the camera at the cable, and not the plug, socket, other plugs and sockets for comparison, the pump, the tub, the cat, my car, the house, the moon............

I checked *everything*, all items involved are now running a little warm, but still at reasonably sensible temps (low 30s as noted) so, as previously stated, I am confident that the plug itself is fine. But I am keeping an eye on it while we use it for the first few days / weeks, and making sure not to run other very-high-load devices on the same ring at the same time.

43 posts in and the OP is reluctant to or does not want to change the plug which is a key element of the problem

There is clearly a minor issue with this hot tub and the OP clearly is not happy with it's operation. Having rejected most if not all of the advice given I would suggest the only conclusion to solve this issue is for him to return it as not fit for purpose

Again, someone who isnt actually reading the posts. I WILL likely be changing the plug/cable at some point once i have run in a suitably rated dedicated feed. But, as i have stated several times, I am not going to irriversibly alter a BRAND NEW product until I am sure A) there are no warranty issues with the core product (the tub, pump, controller, etc), and B) I have a suitible way forward. Just replacing a 13a plug witha 13a plug when (by many accounts) "high load devices just run warm" isnt going to actually solve anything.

Ultimately most of you have ignored my actual question. Which has less to do with the plug itself, and everything to do with the temperatures of all items involved. @dmxtothemax answered it though, and confirms my answers gathered through wider research (and some indirect responses in this thread). So thanks to them.

 

[Midwest]

Yes, i have, and in my personal experience, manufs take a dim view of any alterations to any part of the product within the warranty period. This may not be the case with this unit, but going by precident, i expect that it might. Hence my post here.



Do you really think I would point the camera at the cable, and not the plug, socket, other plugs and sockets for comparison, the pump, the tub, the cat, my car, the house, the moon............

I checked *everything*, all items involved are now running a little warm, but still at reasonably sensible temps (low 30s as noted) so, as previously stated, I am confident that the plug itself is fine. But I am keeping an eye on it while we use it for the first few days / weeks, and making sure not to run other very-high-load devices on the same ring at the same time.



Again, someone who isnt actually reading the posts. I WILL likely be changing the plug/cable at some point once i have run in a suitably rated dedicated feed. But, as i have stated several times, I am not going to irriversibly alter a BRAND NEW product until I am sure A) there are no warranty issues with the core product (the tub, pump, controller, etc), and B) I have a suitible way forward. Just replacing a 13a plug witha 13a plug when (by many accounts) "high load devices just run warm" isnt going to actually solve anything.

Ultimately most of you have ignored my actual question. Which has less to do with the plug itself, and everything to do with the temperatures of all items involved. @dmxtothemax answered it though, and confirms my answers gathered through wider research (and some indirect responses in this thread). So thanks to them.

I don't think you have. As I said in #22, from my research many manufacturers do not mind plug tops being replaced. But the only way to found out, is contacting your retailer or manufacturer directly.

Its important for you to note, that when any connections, wires & cables are subject to abnormal thermal heating, the effects are not just localised or to one part. Running a damaged cable or connection again, then the problem will only represent itself.

If it wasn't a moulded plug, you could take it apart and inspect for damage. You cannot do this, so to rule out the possibility of thermal damage to the plug & supply cable, they have to be replaced. Your plug/cable may be perfectly ok, but there's no way of knowing.

 

[UNG]

Yes, i have, and in my personal experience, manufs take a dim view of any alterations to any part of the product within the warranty period. This may not be the case with this unit, but going by precident, i expect that it might. Hence my post here.

In the 40 or so years since moulded plug tops appeared I have never had any manufacturer take a dim view of changing the plug, the only condition imposed by some was that the new plug was fitted by a qualified electrician

Again, someone who isnt actually reading the posts. I WILL likely be changing the plug/cable at some point once i have run in a suitably rated dedicated feed. But, as i have stated several times, I am not going to irriversibly alter a BRAND NEW product until I am sure A) there are no warranty issues with the core product (the tub, pump, controller, etc), and B) I have a suitible way forward. Just replacing a 13a plug witha 13a plug when (by many accounts) "high load devices just run warm" isnt going to actually solve anything.

Ultimately most of you have ignored my actual question. Which has less to do with the plug itself, and everything to do with the temperatures of all items involved. @dmxtothemax answered it though, and confirms my answers gathered through wider research (and some indirect responses in this thread). So thanks to them.

Recognise this

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.

And you are still using an appliance that got that got so hot it caused it to smell although only socket melted I would of thought it prudent to change a plug that had been subjected to that heat clearly it is you who is SELECTIVELY reading posts until you get the answer you want to hear at least you have a full hot tub to fight the fire just make sure you have a bucket close by

 

[mrwkuk]

I don't think you have. As I said in #22, from my research many manufacturers do not mind plug tops being replaced.

My experience does not replace your experience. There is no reason both cannot co-exist. Most manufs you have talked to say its fine. All the ones i have had dealings with over my 40+ years have had issue with any modifications. They are likely different manufs to yours, hence the discrepancy.

I accept that many probably dont have an issue with it, but for the last time, i am not taking snips to a £300+ product until I am sure thats what is needed and its not going to cause more/different issues.

I mean I did say I personally installed the outdoor socket, that melted. Whos to say i can even wire up a plug correctly?

Its important for you to note, that when any connections, wires & cables are subject to abnormal thermal heating, the effects are not just localised or to one part. Running a damaged cable or connection again, then the problem will only represent itself.

If it wasn't a moulded plug, you could take it apart and inspect for damage. You cannot do this, so to rule out the possibility of thermal damage to the plug & supply cable, they have to be replaced. Your plug/cable may be perfectly ok, but there's no way of knowing.

And you are still using an appliance that got that got so hot it caused it to smell although only socket melted I would of thought it prudent to change a plug that had been subjected to that heat clearly it is you who is SELECTIVELY reading posts until you get the answer you want to hear at least you have a full hot tub to fight the fire just make sure you have a bucket close by

The plug itself, and the cable, did NOT get melting hot, as i could easily touch it to un plug it. It was only warm to the touch. It was only the socket that had any melting, on the inside, and as noted in the original post that appears to have been from arcing due to poor wiring as the "melt" was extremely locallised directly next to the screw terminal on the back, and has now been removed from the equation anyway.

I ONLY mentioned this as a side point before asking my main question.

The plug on the cable has absolutely ZERO signs of any heat damage, and the plug and the cable themselves only ever got warm, not "too hot to touch".

But (for god knows how many times now) my question was essentially how warm is too warm. No other product in my house draws this much continuous current so i have no prior experience with how warm the cables might get. It seems that 10-15°c above ambient is as much as it gets and I am happy with that. But as all the cables on all my other equiment are at (or very near) ambient it was concerning so i came here to ask about it.

So maybe this thread should just be deleted and I will re-post the original post as follows:

I bought one of the inflatable hot tubs recently and the cable and socket is getting quite warm. It seems like its drawing a lot more current that i was expecting but the its within the specs on the box.

Is it normal for something drawing around 11-12a through a 5m cable and a 13a socket for an extended period to get warm? (Around 10-15°c above ambient)

I have looked around a number of other sites and most places seem to agree that the answer is "yes" and "warm is fine" but "hot is bad". So maybe thats the simple answer to my question.

But I cant find much in the way of actual stats. Like cable type X under Y conditions will run Z°c warmer. Or cable type X can get to Y°c without cause for concern.

Obviously thats likely cable and plug manuf specific info, but it would be good to know if theres a rule of thumb. Like "power cables should never run more than X°c above ambient" or "within X°c or Y% of their max rating" or something.

 

[Midwest]

Talking of experience, in my experience when cables, accessories are subject to abnormal thermal damage, e.g. something melts, quite a bit has to be replaced. For example many years ago, when I was newly qualified as an electrician I experienced an electric shower pull cord that had been poorly installed with loose connections and suffered thermal damage. I replaced the pull cord, but through lack of experience, I only cut back the damage part of the cable, from switch to shower I could see damaged. I was soon back, to replace the replaced pull cord, as the cable had suffered thermal damage I could not feel or see. Lesson learnt. Now in similar circumstances, I would replace a good length of cable.

@mrwkuk I’m not suggesting snipping away at your hot tob, but why won’t you ask your tubs manufacturer? They seem offer various spares.

 

[Bappibear]

I also have a hottub mines the lay-z-spa paris specs say voltage 220-240V ~ 50Hz, 2050W at 20°C.
I have fitted a double ip67 waterproof socket on the outside of my shed with the twin & earth cable going into the shed with a double socket.
In the house the lounge has 4 double sockets on a dedicated ring main, 32a rcd, what i would like to do is split the ring at the nearest point which is less than a couple of mtrs away from the shed. Run a 2.5mtr cable into the shed add 2 extra double sockets plus the outside one and then run a 2.5mtr cable back to the house thus reconnecting the ring main. one of those sets of wires coming back into the house would need to be joined together, would crimping be better or choc block??

 

[telectrix]

I also have a hottub mines the lay-z-spa paris specs say voltage 220-240V ~ 50Hz, 2050W at 20°C.
I have fitted a double ip67 waterproof socket on the outside of my shed with the twin & earth cable going into the shed with a double socket.
In the house the lounge has 4 double sockets on a dedicated ring main, 32a rcd, what i would like to do is split the ring at the nearest point which is less than a couple of mtrs away from the shed. Run a 2.5mtr cable into the shed add 2 extra double sockets plus the outside one and then run a 2.5mtr cable back to the house thus reconnecting the ring main. one of those sets of wires coming back into the house would need to be joined together, would crimping be better or choc block??

if you are doing it all from the house socket, split ring, 2 legs out to new sockets, 1 leg into 1 leg of rfc, 1 into socket terminals. joint the loose cables with ideal splice connectors. or wagos.