please can someone help me ,just bought hw100 with stirup pump ,i put about 210 bar in try to unscrew the reservoir as quick as possible ,i lose air when unscrewing as fast as possible .end up with only 150 bar ,instead of 200 bar ,am i doing something wrong ,or could someone help me with this problem ,eg a better way to do it .other than buying a divers bottle ,pllleeaseeeeee!