I have a firebird 70 oil combi boiler. One of the valves/tap was leaking yesterday (see pic) and local plumber replaced the valve. But now I have this odd whirring/siren type noise when the hot water is run, and I also think the flow is down aswell. Have put my ear up to areas inside the boiler and its deffo coming from the new valve area. Faulty valve? My plumber is coming back out this week, but I’m curious what it is.
