Discuss Relieve boiler pressure in the Central Heating Forum area at PlumbersForums.net
Looks like both valves on your filling loop are open the black knobs should be level across.
When you have done that disconnect filling loop of left hand valve loop into a bucket slowly open right hand valve until pressure drops.
The blue one the other is a drain off cock.
Reply to Relieve boiler pressure in the Central Heating Forum area at PlumbersForums.net
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