No recording I’m afraid as it happened so quickly but at 6.00 this morning I was woken up by an extremely noisy vibration coming from my bedroom radiator. It sounded like someone was drilling it with a hammer drill. Even the grill on top was rattling and you could really feel the vibration. My first thought was that something was broken inside the circulating pump (heating wasn’t on but the hot water is on 24/7 and it comes on as and when) so I went downstairs to check it. The pump wasn’t working and there was no vibration was coming from it but even from downstairs I could still hear the noise coming from my radiator upstairs. I checked the other upstairs rads and they had a very faint vibration but the main culprit was the rad in my bedroom. Eventually the noise quietened down and stopped. The whole event lasted about a minute. Another thought was that it might have been the pressure relief valve letting by (sealed system) so I went outside to check that and it wasn’t. I put the heating on and it fired up, working correctly with no noise from the pump. I have no idea what it was - any suggestions?

