I've just drained the system to fit a new diverter valve to my Vaillant VCW-sine 18 T3WF H, plus changed some old TRVs as well.
Is there any reason not to add inhibitor when I top it back up? The manual makes no mention of adding it, and I've heard older boilers don't like it.
I'm pretty sure...
I was hoping there was something I could try with switches/sensors/valves on the water side? It seems like there's a switch not making, Possibly due to water temperature?
Problems with my trusty old Vaillant.
When the central heating or hot water tap are turned on, the main burners will ignite as normal. After a second they used to come on even stronger, but this no longer happens.
Result is warm, but not hot tap water; and central heating that take...