I'm having the same problem. The system pressure will increase too over 2-3bar and shut off from a starting position of 1.2bar. If I start from a position of a half a bar then I can only set my temperature to around 50 degrees for the system to stay under 2bar and remain on????
Ron McDowell
December 2017
Thanks for advising of the A26 fault code. My water pressure was too high. However, when I lowered the pressure by draining water from the system, the fault code would not go away. There was one more act to play and this was to press the reset button on the panel. Glad to say the system became operational once again
Gary
January 2012
check your water pressure and see if its over 2-3.just means when the the water pressure on gauge has gone too high more than 3 times, but its not in the manual .just drop the pressure from a vent on a radiator or a drain off till the pressure is just above one bar
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