drain some water out of the radiator system via a hose pipe connected to the drain valve usally found at the pipe work at bottom of rads
floyche, December 2009
check the filler loop is not letting past, then bleed some water out through the air bleed screw on a rad, will need a old towel and a small container to catch the water stop at about 1 to 1.5 bars cold pressure .
wirecutterman, November 2009
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I can answer this question...
how can i lower the pressure in my valliant eco tec boiler?