Gaelicsheep Gas bottle is 7 kg butane and our heater is a smaller version (2 settings) of the more commonly used 3 setting one. Believe it or not we get the refills from a house removals/storage service firm who do a sideline in gas bottles. DH says the next size up to ours (presumably for 3 heater setting fire) is £23.
on the question of whether it's cheaper to have the heating on all the time, or twice a day, we did a test last year by taking meter readings over several days with the boiler set to different times.
We thought it was only 1 or 2 units extra to have the heating on for the majority of the day.
Oh how wrong we were! We thought that the units on our meter translated to units on the bill. We didn't look at our bill and use their calculations to forecast our bill, so we were hit with a whopper. We're still paying it off and look to be doing so for a loooong time. We can't move to a cheaper supplier unless the new one would be willing to take on the debt we've wracked up with our existing one .
So this winter we're going to see if we can upgrade the timer on our boiler to have different settings, and currently the heating and hot water is set to come on for 3 hours in the morning and 3 hours in the evening. It goes off at the time DH leaves for work, and again when DS goes to bed. DS is with this GPs all day for 3 days of the week so gets the benefit of their heating while I'm at work. If I wasn't, I think we'd be spending a lot of time at the library
Please do not put any sort of portable heaters in your childrens bedroom. Last week i attended the funeral of my friends 3 year old daughter who received 90% burns to her body after her nightdress got caught on a heater that they was using to warm the house through. She survived a further 6 months after her accident but sadly could not fight any longer. Please be careful, i know heating is expensive! We have invested in thick curtains, carpets and blankets. Not cheap now but in the long run will work out better.