q - I have always thought there should be an way to control the time limit without resorting to tripping the fuse switch..
I assume this method is not possible on an electric shower as opposed to a shower pump.
It's possible on both types of shower.
I have a shower pump - in the hot press
and a Triton t90 - timer is beside the fuseboard
I had to put timers on both of them.
A Triton T90 is a 9kw water heater. That costs a lot per hour to run.
You will see an immediate result on your next electricity bill if you put a timer in.
Example: 1 Triton T90 used 4 hours per week adds up to easily €54 per electricity bill.
Source below.