On an Ideal Isar, when the central heating is on, if the boiler displays "d" meaning there is a demand for hot water (when theres not, no dripping hot water taps either) , does it mean the diverter valve needs replacing?
The boiler is three years old and intermittently heats the hot water. Thanks in advance!!
The boiler is three years old and intermittently heats the hot water. Thanks in advance!!