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I've a long-running issue where my Vaillant EcoTEC Pro Combi boiler cannot supply hot water at higher flow rates (though well below the 9.3 l/min it is theoretically capable of).
Looking through the diagnostic codes this evening, I noticed D.003 ( Outlet temperature actual value ) is showing as -99c.
Could this suggest a fault with the DHW outlet sensor, and if so, might that be the cause of the poor water heating?
Looks like the part in question is this:
103430 NTC sensor (DHW heat exchanger)
I also very roughly measured the flow rate out the tap, and that was about 30% higher than the flow rate the boiler was reporting, so my other thought is the flow rate sensor is faulty.
Looking through the diagnostic codes this evening, I noticed D.003 ( Outlet temperature actual value ) is showing as -99c.
Could this suggest a fault with the DHW outlet sensor, and if so, might that be the cause of the poor water heating?
Looks like the part in question is this:
103430 NTC sensor (DHW heat exchanger)
I also very roughly measured the flow rate out the tap, and that was about 30% higher than the flow rate the boiler was reporting, so my other thought is the flow rate sensor is faulty.
