As I shall be away for about 6 weeks this summer, I intend to turn off the gas supply at the meter. Do I need to do anything special/take any precautions when I switch back on (or even before I turn off?) I have a fairly new condensing boiler and don't want to do something stupid to break it. Obviously I'll set the timer to 'off'. I saw that report about the explosion this weekend and it made me think.