RCD 'trips out' when Sauna is switched on?

RCD 'trips out' when Sauna is switched on?

Sometimes (usually with non-Sawo Stoves!) the RCD (safety tripswitch on the household fuseboard or consumer unit*) 'trips out' when sauna is switched on, or very soon afterwards.

(* RCD switch has a 'Test' button next to it)

This 'problem' most often occurs when the sauna has not been heated for some time.
(Also, usually with other brands, when the stove or elements are newly installed)

It will not usually occur/recur if the sauna has been or is regularly heated.

It is very often (usually!) caused by invisible dampness inside the heating elements.


Please utilise the services of a fully qualified electrician - Your safety is paramount.


If dampness (e.g. as a result of a long period of non-use) is considered to be the most likely cause of the problem, first check that all appears to be otherwise normal, then try:

Re-setting the RCD (maybe several times…) until enough heat is built up to drive off the moisture inside the elements that is probably causing the problem.

(Note: There is little point in trying to ‘dry’ the stove by other means, e.g. hairdryers!)


If re-setting the RCD (note it may take many attempts...) does not work, it will be necessary to follow a slightly more involved procedure which should only be carried out by electrically qualified persons.

This problem will usually be completly avoided if the sauna is regularly heated, so - enjoy it often!

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