Worcester 24i - hot water but fails on central heating demand

[psimmons]

Hi all, I couldn't find a similar issue so hopefully you won't mind my own thread.

My Worcester 24i Junior Greenstar combi is providing hot water, but on central heating demand it fails after ~2 minutes to the flashing blue light. It was installed 4 years ago; pressure is 1.5bar

On getting central heating demand, it rumbles to life, water can be heard gurgling inside, the green ignition light comes on, goes off, comes on, but after 2mins or so it gives up and the blue light flashes. After being reset though, it will merrily provide hot water to the taps.

Any ideas what the problem might be? Does the fact the hot water is fine mean the pump will be OK? Or is the pump not used for hot water?

I know I'm going to need a professional but it would be good to know what the issue could be and scale of £££ expense I might be facing if this is a problem anyone's encountered before!

Thanks, Paul

 

[Agile]

You should never hear gurgling which could indicate that there is air in your system.

It sounds as if there is air in the system and that may mean the boiler needs and engineer's bleed internally.

In many cases that sound would indicate a blocked condensate outlet. But that would usually also back up on hot water as well as heating.

But just in case, try to disconnect the condensate pipe and see if its blocked.

But don't remove the boiler casing as that's part of the room sealed design which makes it safe.

Tony