What is causing RCD to trip repeatedly?

If it trips the RCD then you have an electrical fault. Washing machine can do this once they are a bit old, or if they have had a water leak. The water gets into the electrical equipment and causes a fault that trips the RCD. If you have a circuit without an RCD try that. If it still trips, then the fault is serious and you will need to get it repaired. You can also try putting the washing machine into a warm place for a few days to see if it will dry everything out. Sometimes this will cure a fault if it is due to dampness.

rcd units trip from the milliamps that are in a short
it trips the rcd to prevent electrocution and acts in nano seconds besides being a circuit breaker for excessive current
the trip can be from moisture allowing a current leakage to ground or some other simple operation
I suggest that you get in a qualified electrician / bosch service technician to find the reason for the problem rcd

as an appliance engineer sometimes the oven element can be at fault, although this always the case, it could be the thermostat also as they are both interplay when the oven is heating up, they could both be tripping the RCD as the earth is detecting that electricity is becoming live due to a component leaking electricity.
you could try replacing both of them with caution (turning the electricity off in the house ect.. using safety equipment)

a good site to use for those components is the following;

Spare Parts Accessories for Electrical Appliances QuickSpares

usually if they don't have the item in stock on the website you can use the contact option and they usually respond pretty quickly and let you know if they can get the item ( most likely )

IF the warranty is still in effect, call for service.
IF no warranty, then check the heaters for the solid inks.
Probably a bad element, or a shorted element.
Unless you are skilled with electrical meters, V-O-M type,
this could be dangerous.
DO NOT ATTEMPT to troubleshoot this with power on.
IF you can use a meter, with the power OFF,
check for continuity and resistance with multi-meter set to Ohms.
BE CAREFUL!
Electricity can KILL!

have a technician come in and do an insulation test on the unit
the very smallest insulation leak will trip the RCD unit in the breaker

Hello,
It would seem to me that the heating element needs replacing from the information you have supplied especially as it performs most of the other functions like filling and spin and drain.
Good luck

electrical short in m/c.could be heating element. regards

I suspect not the oven element at fault. you only way forward is to actually test the resistance of the element to earth with a megga if you can beg the use of one. be cautious about the result as on occasion, elements are only faulty to earth when hot. another way to test if you are cdarefull, is to connect the element to mains independently of the oven and see if the rcd trips

i had this probem and apparently there's a 'float switch' in the bottom of the machine. This switch is a safety cut off and when activated can not just stop the machine but trip the electrics in the house. the reason for it activating is when food clogs up the drainage bit water can not drain and fills up the bottom of the machine. this then activates the 'float switch' as a kind of safety cut off.
the way to sort it is to disconect the machine from the mains and drain and water. empty the clogged up food from the drain bit. then tip the machine back and a load of water will pour out (may need a load of towels for this bit or take the machine out the back and do it)
once this is done, plug it all back in and give it a try - works for my machine, good luck.