Conventional boiler (Potterton Promax HE) and tank (Drayton HTS5) set up with timer for heating and hot water. Over last few months water in the tank seems to be running continually, and the boiler firing on every five minutes or so – the hot water is scorching hot. This happens even when timer is off!
Definitely there is some kind of leaks from the water heater. Did you called the plumbers to know what exactly the problem is? If not, now is the right time to do so.
This are some common issues with water heat tank, however, if not solved early it can lead to some serious problems. Hence, consider taking help of professional plumbers to get rid of the problem.