Tripping sauna

Simon Slater · Mar 25, 2020

I have an existing indoor sauna that hadn't been used for sometime (used plenty before though) and I recently cleared it out and renewed the room its housed in. When switching the sauna on it starts fine for 2 - 3 mins and then trips the RCD switch. So I read online very similar issues but none ideally match my problem. I will give more details below but my basic question is...Is it the Sauna or something else, I'm happy to buy a new one just don't wnat to throw good money away.
The sauna is wired very professionaslly from what I can see. It sits on its own circuit to its own breaker switch with a 35amp fused on and off switch. I've tried isolating the elements (3 of them) and all elements work properly on their own but with 2 or more the breaker trips after a few minutes on. The only thing thats changed since it last worked (other than time as its not been used for about 2 years) is the 35amp fused switch which I changed (I changed it back to the old one and it still tyripped). The Sauna is a dated Harvia Kip60

I'd appreciate any suggestions, as said happy to buy a new one but want to be certain it is the old one thats the issue.

davesparks · Mar 25, 2020

Heating elements which have been left idle for a long time can absorb some moisture from the air, this will create a small earth leakage.
If any one element works on its own but when any two are on together it trips then I would suggest that each element has a little damp in it.

If you can safely run each element individually for a couple of hours to get it hot and drive off the damp you should find it then gets back to normal working.

Simon Slater · Mar 25, 2020

davesparks said:
Heating elements which have been left idle for a long time can absorb some moisture from the air, this will create a small earth leakage.
If any one element works on its own but when any two are on together it trips then I would suggest that each element has a little damp in it.

If you can safely run each element individually for a couple of hours to get it hot and drive off the damp you should find it then gets back to normal working.

Thats a good idea I'll try that...cheers

Simon Slater · Mar 27, 2020

davesparks said:
Heating elements which have been left idle for a long time can absorb some moisture from the air, this will create a small earth leakage.
If any one element works on its own but when any two are on together it trips then I would suggest that each element has a little damp in it.

If you can safely run each element individually for a couple of hours to get it hot and drive off the damp you should find it then gets back to normal working.

Give that man a cigar! I isolated each element as before but as you said I left each one running for an hour or so and then put it all back together and hey presto it works like a dream.

Thank you muchly

Simon