230-250v Mains power supply problem

I have a new Steam Sauna/Shower designed to operate from 230-250v house
supply and have struck problems. The finger control console will not respond inside my home!! It worked correctly in one out of six neighbouring dwellings,and tested in a car outside my Garage using a 12v car battery & 230-250 v inverter,it once again performed perfectly. This mystifies two of our
qualified electricians!! The power supply has been tested by the electrical supply company and given the all-clear. The house wiring is through a RCD protection unit and once again checks out o-k. Have tried putting through a transformer also a power filter but still of no avail,and I would appreciate some
helpful idea's on this. This unit also worked perfectly when tested in another house 3 kilometers away from my home,and have even replaced the control box and console with a new unit with exactly the same results.Ruling out R/F
interferance it still looks like a mains supply problem,but what? is the leading question?

is the unit not by acsident swiched in a pre programed operating mode??
where you don't need a controll unit for

i have some experiance in steam sauna controls
maybe a faulty conector
did you open up the machiene or not

Robert-Jan

rjvh

Robert-Jan,
Thank you for your reply!! The finger touch console is inside the unit cubicle
and the control box is fitted to the back,and both are required for operation.
I removed both to take to other dwellings for testing,but to break the seal to gain ac'cess to the control box interior would void any warrenty. However i do intend to do this has a last resort!!
Regards
Jim