Meister manor has a little pump in the airing cupboard which switches on and boosts pressure when someone takes a shower. A while ago it started switching itself on for a second or two in the middle of the resulting in a burst of noise interrupting my much needed beauty sleep. The reason was a drop in pressure in the expansion vessel and was fixed by my plumber who recharged the little expansion vessel attached. The random switching on has started happening again. Annoyingly a couple of weeks after the boiler has been serviced so rather than call Mr. plumber out again, I've been researching fixes. It would appear that I can just pump up the expansion vessel a bit and as such I've been researching car tyre inflators. Whilst the meistermobile is provided with a tyre inflator, it's cigarette lighter only and designed to work with the tyre expansion goo kit (no one seems to do a decent spare wheel anymore). It's also in it's sealed case in the boot and I don't really want to crack it open if I can help it. I have a foot pump but the analogue gauge on it is unreliable. Looking at on-line reviews most of what's available seems to be fairly crappy or unreliable so I'm wondering if the good people on here have any recommendations. I'm looking for a digital car tyre inflator, Preferably with mains and car cigarette lighter options although I can get a mains adapter if necessary.