Both the franke and jura are identical...as is the mantaya C100. Answer.... the steam thermoblock (Heater) has two components likely to cause this, A thermal fuse and a thermistor. The root of the problem is that the main board is not seeing the correct reporting. Check both these items (cheap to replace) and then if not successful, start worrying in case it is the thermoblock itself
pearlypaddy
December 2009