My friend had the same problem on his motor home and it turned out to be a faulty RCD. The manufacturer had installed a cheapo.

Hi all. Please don't worry, we are not attempting to fix it. As said on a previous post, we are booked in for it to be investigated but not until the end of the month, at which time I will give you an update. 

its  just that inquisitive mind that wants to know what's  going on. 

Waasa- we've already had the RCD replaced. 

Thank's again for the interest. Will keep you informed . 

regards Stuart