Hi everyone! At a loss with this boiler, any suggestions would be much appreciated! Please see below... Worcester Bosch Greenstar 28i Combi Gas Boiler Whenever it is really cold outside my boiler decides to switch itself off (6 times in 1 1/2 years). It is under a service contract and warrantee with British Gas which I have called out three times. Basically the system seems to have a mind of its own (other than this switching off issue) the thermostats are set at 18 day and night yet one minute its so hot you cant bear it and the next its too cold to move! Things that have happened recently are the annual service performed by BG and I replaced batteries in clock/timer thermostat (as thought may be the cause of one or both of the problems) This has been a problem since British Gas fitted this brand new boiler Whenever we get a cold snap it happens British gas keep saying they cant tell what is wrong unless they see what lights are flashing at the time of the system failure...?? Surely they can plug something in to identify a fault like they do with my car?? They have come out three times and each time have said they cant work out why it is doing it and they say watch the lights and let us know what they do when the fault occurs (which I have - the light was off, not flashing or anything) but still nothing done. Have tried the troubleshooting section in the extremely brief manual for 26i/28i Junior model and still at a loss. At the moment since I pressed the re-set button followed by the on/off button when it failed to start up at the weekend after it switched off, the over-ride light (and button which incidently do not feature in the manual at all) is on one minute off the next then flashing intermittently the next.. could this have anything to do with it? Really fed up with it now, Please help!!