What should the pressure be in the expansion vessel with the system drained ie no pressure.The boiler is a Baxi 105HE it states in my installation and service instructions that this should be a minimum of 0.5 Bar?
0.5 bar is the minimum so inflate to (more than 0.5>bar )
Inflate to 0.8 to 0.9 through the car valve (1 BAR MAX) then refill the system up to 1 to 1.5 bar pressure COLD.
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