My boiler was fitted in Sep 2005 - it is wall mounted behind a kitchen cupboard with horizontal flue directly out the back wall. Last Nov water started flowing out of the bottom of the boiler, through the grills in the cover, which coincided with a heavy downpour. Heating repair guy came who had incidentally fitted the boiler; couldn't work out where water came from but resealed around flue inside & out - boiler restarted ok as it had dried out. On Monday same happened, again heavy downpour - turned off boiler, called guy again - I tried to see if water coming from overflowing gutter, but don't think this is the problem - Heating guy did a lot of head shaking & 'never seen this before' - he had no idea where water was coming from as the whole of the inside of the boiler was wet, suggested changing flue to roof exit or another wall! That night another downpour & you guessed it - flooded kitchen. The surround of the flue pipe inside the house leading to the boiler appears dry. In all likelyhood the boiler is now dead and I will have to have this replaced but I want to find out where the water is coming from before I spend more money - any ideas ? Is it worth contacting the Gas Safe register for advice ?