Please help! We were woken a few days ago by loud noises from the airing cupboard. It sounds like water being dropped into the tank from a great height. Coincidence perhaps, I'm not sure, but our boiler downstairs then stopped working and we have just had a new motor fitted. The noise from the tank is still there. There are 2 radiators in bedrooms above the airing cupboard and they are full of air but bleeding them does not help. They hiss for a few seconds, then nothing. All other radiators in the house are working fine.