I have an 9 year old Range Tribune HE unvented cylinder thermostat connected to a Vaillant VR66 using the cylinder thermostat terminal but when the thermostat is closed there is a 12v signal registering (Vaillant say it should be 0v.) which is causing the boiler to keep firing and hold the hot water valve open until the time program for hot water ends.
Range say it's impossible for the thermostat on the cylinder to allow any voltage past if it is closed. Is this correct? Is the 12v coming from somewhere else?
Maybe I should add that the thermostat is the double probe type one probe controlling the emergency cut out.
Range say it's impossible for the thermostat on the cylinder to allow any voltage past if it is closed. Is this correct? Is the 12v coming from somewhere else?
Maybe I should add that the thermostat is the double probe type one probe controlling the emergency cut out.
