the heatbank has an adjustable thermostatic mixing valve on the boiler return, that appears to mix water from an tapping near the base of the heat bank with water from a tapping at the top of the heat bank....presumably to control the temp of the boiler return to get the boiler into condensing mode all the time.... but why is it needed? why not just take the boiler return from the bottom tapping full stop?
also it has two electrically interlinked thermostats vertically spaced but only by about 100mm (heatbank is abt 2000mm tall) both are set to 60 degC ?
Seems only way for heat to be called is by using the HW channel on the programmer. CH side of programmer causes radiator circulation pump to run but not call for heat (even when hbank temp down to 40deg C on gauge)???
Anyone else have a heatbank and recognise any of this? or has he got a lemon ?