I had this tankless installed now for 6 years with no problem at all.
But now for some unknown reason, to me, randomly throughout the day it starts up fires the flame then shuts off. It can do that once or in multiples of 5 at a time.
I could understand if there is water flow but there are is no water going anywhere including leakage within the system.
I had just completed a descaling which did nothing but clean the unit.
My thoughts are that since no one instigates the water flow that there must be a sensor within the unit that erroneously thinks that water is flowing and starts the heating process.
Any thoughts on this problem would be greatly appreciated.