hot water and central heating wont work independently
We have a conventional heating system I have recently had a new boiler fitted (not a combi boiler). We have a problem whereby the water cannot be heated up without the central heating coming on aswell. We have had one of the 2 zone valves which was deemed to be faulty changed, however this has made no difference.
Could it be the other zone valve or an electrical connection between the timer and boiler or something else?
Any advice would be appeciated as the only way round it at the moment is to switch off radiator valves when the hot water is heating -not ideal.