Oh. Oh I wish my consumption was only 800 litres a year !It's a 3 bed end of terrace with 1 bathroom and 1 en suite, though that is only an electric shower and 8 rads. The original system was coal boiler (Trianco) fitted by my dad 42 years ago, 20 years ago it was revamped with an oil boiler, (boulter Camry 5) never serviced until I took over the property last year.
Oil we use just about 800 litres a year occupancy 2 adults 3 kids on a part time basis as we're doing it up slowly
My last delivery was 3000 litres and that will last about 6 months. Three oil boilers on the farm (all Grants) System boiler for the house, combi shared by the two one bedroom holiday cottages and my office and another combi for my workshop. House has a wood burner in snug and sitting room that are the main source of heat. Just loaded, dumped, split and stacked three truck loads of ash that should last hopefully three years.