[QUOTE] Yup. Yes, pressurised. It's now got a nice lot of expensive anti-freeze in it. I'm not sure I CBA to drain/refill it everytime. [/QUOTE] So is that a 'chauffe eau' independent of the rest of the heating system ? Can't see how I could get antifreeze in to our 'ballon' .[QUOTE] I've also now sent off for a new thermostat with a built in webserver - internet-appliances-r-us. So I can monitor the temp and turn the heating on and off whenever I feel like it. [/QUOTE] Neat - assuming the power never drops out. I thought of similar solutions here (except for electrical heating rather than oil) but couldn't come up with a way to reset the master 'disjoncteur' in the case of that tripping out. I suppose I