without getting a manual out, Does the pressure need to be 2 bar? Most systems require 1 bar, At 2 bar, it will go over pressure very quickly. over pressure release units tend to operate at about 3.5 bar, So unit would complain if it went to that. Check your user manual, if you do not have one, try googling it. when the system is cold, set the pressure to correct level, go on from there.
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