Worcester Bosch [2910] fault codewhat it means and how to fix it

2910 is a locking fault on the Greenstar 8000 Life, 8000 Style, 8000+, 4000 and 2000, and the description Worcester print is simply fault in flue system. The remedy list is short and every item is an engineer's: check the flue for obstructions and remove any found, carry out the flue integrity test, and check for water in the sump and the operation of the siphon.

The last is less odd than it sounds — the 8000 generation's condensate siphon sits in the flue gas path, and if it is not draining, water collects where the combustion products should be leaving and the boiler reads it as a flue problem. The Greenstar 2000 adds a related code, 2918, fault in combustion control, whose only remedy is to clean the siphon and drain water out of the appliance on the gas side, which shows what Worcester have in mind.

What the code is not is a nuisance. A boiler that cannot be sure its flue is clear is a boiler that cannot be sure where its combustion products are going, and that is why it locks rather than blocks. Worcester's own remedy makes the flue integrity test part of clearing it. The householder's part is small: look at the flue terminal outside for anything obviously blocking it, check the condensate pipe is not frozen or kinked in cold weather, and do not keep resetting.