Hi all, I have the common problem of heating working fine but hot water only warm. I know the usual places to look starting with the 3 port valve etc. However having changed the valve and flushed the system problem remains. What I have noticed and worked out is the motorised actuator at first appears to do what it should. However if i run hot water only it heats up fine. If I have it on both hot water and heating radiators it fails to heat water tank (sealed) much. This is why I first thought it was the valve itself (valve not shutting properly)
When it is on radiators only the lever is fully across as it should be. However when I turn hot water on although the lever moves to the mid position as it should it only moves just over a third of the way rather than half way.
My question is should it move all the way (it is a Danfoss HS3, 14 years old) to the half way point and if this is the cause of water bleeding towards the radiators rather than the hot water tank would I need to replace the whole motorised part or just the synchronous motor? The manual lever moves with the motor/spring as I believe it should other than not returning to the centre when hot water/radiator called for. Or do I need to look elsewhere such as possible old weak water pump (my next port of call if not the motorised valve) ? Any help would be most appreciated.
When it is on radiators only the lever is fully across as it should be. However when I turn hot water on although the lever moves to the mid position as it should it only moves just over a third of the way rather than half way.
My question is should it move all the way (it is a Danfoss HS3, 14 years old) to the half way point and if this is the cause of water bleeding towards the radiators rather than the hot water tank would I need to replace the whole motorised part or just the synchronous motor? The manual lever moves with the motor/spring as I believe it should other than not returning to the centre when hot water/radiator called for. Or do I need to look elsewhere such as possible old weak water pump (my next port of call if not the motorised valve) ? Any help would be most appreciated.