Combi boiler leaking water

[ntl142]

My Unica 32 HE is slowly dripping from the CH fitting under the boiler and its slowly losing pressure. Looks like it's been dripping for a while now. Are these compression fittings and can I just nip it up a touch to try to seal it or will that likely cause other problems? Any other easy options to avoid draining the system and replacing the fitting? Thanks.

 

[Madrab]

Sometimes backing the nut off a 1.4 turn and then nipping it back up works if it's an olive/fibre wahser. If it doesn't stop then it's a drain down and wrap/re-washer the fitting.