6Kw Sauna

[new_spark]

Hi

I apologise in advance for lack of knowledge i this subject as I only work in domestic, a mate owns a commercial gym and has a 6 Kw sauna heater which comprises of 3x 2Kw elements.

He asked me to look at it as he has fallen out with his normal electrician over prices, he told me that he has had a few problems with it in the past which is normally related to the elements failing.
The fault as described to me was that it just wasn't working.

I started at the board which is a 3 phase board, the sauna is on a single phase 40A RCBO, which was in the off position, after isolating the supply at the RCBO I traced the 10mm T+E to a 45A DP Switch which was checked and isolated.

I then dismantled the heater and checked continuity on all of the elements, all appeared to be working, then I traced the wiring back from the heater which is some type of heat flex it has 6 cores and earth and appeared to be 3 line conductors and 3 neutrals. I then followed the cable back to a IP enclosure which was on the side of the sauna in quite a humid area, the cover was off and I found the mess in the picture, no wonder the RCBO had tripped!

The contactor is a Moller Dil 1M, it appears to overheated on the neutral supply side which is fed in 10mm T+E going back to the 45A DP switch as mentioned earlier.

My questions are, why would the original installer have fitted a contactor, it's not high voltage switching and more importantly, why has it over heated? The cable sizes would all appear to be correct and judging by the heat damage the RCBO has only blown when the Neutral cable has burnt completely through and broken the link.

I have disconnected the entire supply from the board and removed the contactor, I've told him its beyond me and told him to get the yellow pages out!

 

[JD6400]

It would appear to have been bodged when it came to the field wiring , there should be only the one feed to it and as far as i am concerned , anyone that uses a cpc for a line conductor , be it sheathed or not , needs dragging outside and shot ( preferably after a good kicking for being such a badger !) .
If memory serves me correct you may need to fit a door switch now as well or you will be contravention of some new brussel sprout rule or something !

 

[PC Electrics]

I have disconnected the entire supply from the board and removed the contactor, I've told him its beyond me and told him to get the yellow pages out!

I hope you weren't so un-diplomatic! You could have said that as you're newly qualified, you haven't dealt with such a system before so you need to get some more information and maybe some help.
Get the sauna fixed for your friend and some learning for yourself.

I'd be willing to help if you wish to discuss terms. I'm less than an hour from you, though there must be someone here who's nearer.

You're to be applauded for asking though. There's many who would have just bodged their way through it and learnt nothing.

 

[PC Electrics]

It would appear to have been bodged when it came to the field wiring , there should be only the one feed to it and as far as i am concerned , anyone that uses a cpc for a line conductor , be it sheathed or not , needs dragging outside and shot ( preferably after a good kicking for being such a badger !) . AGREED
If memory serves me correct you may need to fit a door switch now as well or you will be contravention of some new brussel sprout rule or something !

Door switch eh? is that to turn off the heaters if the door is left open then?

 

[new_spark]

Yes the 45A switch is also in the humid area coincidentally the face plate was also unscrewed from the surface box! I've got to go out now, take the good lady out for a meal but I will let you know on that offer PC, need to know more about the control unit on the outside of the door as well!

Cheers

 

[Knobhead]

If you will pick me up in Nottingham (I can’t drive now) I’ll have a look for you. a couple of pints in the big Forester’s and your sorted.
You're doing the work!
PM me.

 

[JD6400]

If it is in commercial use then i believe it is the law now .
So it is prevented from waisting to much energy with the door left open .

 

[JD6400]

If you will pick me up in Nottingham (I can’t drive now) I’ll have a look for you. a couple of pints in the big Forester’s and your sorted.
You're doing the work!
PM me.

Tony , your a good man , if i remember right this is not the first favour you have offered with the Foresters en route !:54:

 

[Knobhead]

I'm cheap, and so is the beer!

 

[Knobhead]

But it's as good as me :sad_smile:

 

[JD6400]

Just good value for money !:wink5:

 

[Knobhead]

Tony , your a good man , if i remember right this is not the first favour you have offered with the Foresters en route !:54:

The Foresters is on the way back once we’ve sorted out what needs doing. I may be an old soak but there’s thing you have to keep in the right order.

I’m more than happy to help new_spark, but it will be pointing the right direction, not me doing the job.

new_spark, I’m not the two headed ogre that some will have you believe. Sometimes I’m almost human!
The biggest factor is if we need cable and/or a contactor. The contactor is an off the shelf item, the cable??? One thing is for certain the contactor has to be outside the sauna, preferably near to the control unit. Unlike someone suggested the heat doesn’t cut off as the door is opened. Does your oven at home cut off when you check on the roasties?

Drop me a PM

 

[JD6400]

If you goggle " Oceanic oc-sa ll instructions " this will give you some ideas of what is needed , this is the one i have .
The cable will need to be at least HO7RN-F , as for the door switch Tony it was a note on a separate piece of paper that came with the controller saying it was now a requirement if being fitted on commercial sauna's , I can only assume it is to stop people just leaving the door wide open and the sauna on after they have finished ?
The controller can either be factory built in to the heater or on the outside of the sauna only !

I think i will have to grab a bottle of Batemans out of the fridge and me copy of the regs and go for a period of contemplation in the sauna now ! Good call what ?