Yes the pressure when empty of water is 0.4 bar which is what at least one person inn this discussion said it should be. So I am not longer concerned with the accumulator. I am pertty sure the one way valve is the problem. I hop to find a replacement tomorrow, or at least to be able to clean it properly. There is no sign of debris and I always triple filter my water when I fill the tank. I guess its just old age!
Ya Fohi - Amel 54 #98