boiler in the red at 4 bar how do i reduce pressure?

Reduce the pressure from a radiator or drain valve on the radiator system. Do not use the automatic PRV in the boiler as this can get debris stuck under it and will continue to leak/let off pressure until its changed. It does not matter if you let out too much pressure as you can always refil with the filliong loop at the boiler.

Manymetal
February 2010