Your OSO electric hot water cylinder is located within the storage cupboard of your apartment.
The controller for the water is also located here. You will need to progamme the controller to set the timings to provide hot water as required.
Any faults with the immersion heater or the time clock will be covered under the warranty. It is suggested that the time clock is checked for power and to identify if it has tripped on the fuse board. If something is tripping out the electrics, it would be down to the occupier to identify where the issue is by unplugging all electrical items, resetting the switch and plugging the items back in one by one.