Hi, We bought an old house in Aisne in August which has a relatively new De Dietrich 'fioul' boiler in the cellar. It heats around 9 radiators and the hot water system. We are unfamilar with such a heating system and have listened so far to the advice of the previous owners. We stay at the house just two weekends a month and we were told to set the heating to '3' (its minimum setting) when we leave the house in summer and '4' during the winter so the pipes dont freeze. We have followed this advice but we've realised that, particularly recently, that the boiler is using a lot of fuel whilst we are away (around 100 litres a fortnight). All the radiators are on the frost symbol (except a single master radiator that cant be altered) and the boiler is set to 'manual' and therefore not using the room thermostat. I read in the faq entry about anti-freeze for the boiler radiator system. Is this a possibility and if this is present is it OK to turn off the boiler between visits? Any advice would be really appreciated as its costing us a lot more than we expected. Ian