so, i have an ideal logic combi boiler which although working seemingly well , the pressure drops to almost 0 when not use, mainly overnight. I do not need to re-pressurise the system as when i turn on the heating it raises to around 1.3 on its own and around 1 or just below if calling for hot water.
All radiators are full and all but one are fine apart from a cooler spot to the bottom of a bedroom one, no visible leaks.
we have two small boxes in a upstairs cupboard,with little levers on that slide from one side to the other joined to a pipe that disappears behind the void.
The box/pipe that we believe to operate the upstairs heating makes a disturbing rattling sound for upto a minute when coming on, it scared me a bit so had a BG call out under our plan and he was very dismissive saying dont worry about anything in there its just airlock, fiddled with the nearest (bathroom) radiator and left.
this has been the case for upto 6 months now, the rattling does eventually stop on its own accord or if i set the thermostat to 2/3 degrees lower upstairs the rattle doesnt occur.
Apologise if i seem to have gone way off track here, but is it worth me getting them back for a second opinion, could my boiler be an accident/expense waiting to happen or is it a case of all heating and water is working fine so dont worry about it?
thank you in advance