Worcester 28cdi Boiler

[Eric Hall]

We've a Worcester 28cdi boiler which is 7rs old. It's been no bother at all since its installation however it is now running intermittantly when in DHW mode. All works ok upon demand for hot water, the boiler then runs for approx 2 minutes before shutting down for 12/15 seconds, fires up and runs for about 1 minute , shutdown sequence repeats. It runs continuously in CH mode. Water pressure and volume are ok......could it be as simple as a blockage in the hot water filter.......any suggestions.

Thanks all.......not been in here for a while :-)

[Roger Hersee]

Suggest you check the operation of the diverter valve. This diverts boiler water through a DHW heat exchanger when hot water is drawn off (in preference to central heating). If yours has a diaphragm to detect water flow and redirect boiler (CH) water, the diaphragm has probably failed. You may have a noisey operation when drawing hot water, due to boiler water escaping through the diaphragm. Easiest to change the whole part but you may be able to take it apart and replace just the diaphragm (if this is what's wrong with yours).

When it comes to changing your boiler, avoid WB unless you're happy with poor customer service.

Roger