I have a Valliant instant gas hot water system. The cold water is pumped from a tank, ie. it’s not town water. The pressure is very good, but the pump does turn on and off continuously throughout operation. Our hot water fluctuates badly in temperature and pressure, worse the further away from the gas heater ie, the tap closest to it gives continuous hot water if turned on fully (cold water if only turned on a little), at the other end of the house the shower gives fluctuating temp and pressure – the gas heater turns on and off. It’s a normal shower head, not water restricting (we did try a restricting shower head but it made the problem 10 times worse).
Any suggestions to fix the problem – is it the pump causing the problem? Can we improve the pump or should we change the hot water system?