Is my hot touch percolate dropping my boiler pressure? My combi boiler drops pressure when its off, which indicates a small...

My combi boiler drops pressure when its off, which indicates a small seepage. I've noticed a slight drip on the pipe underneath my sink, which is the hot touch pipe. Is this the cause?
Answers:    Remove the cap on the radiator valves, and hold a good surface round for dampness, it doesn't enjoy to be wet through to drop pressure, depends how like a shot the pressure drops. Otherwise it's likely to be as foobix say.
If the tap is cause the pressure to drop you have bigger problems than a washer bleak. The heat hose down, and the domestic hot water don't mix.