I am renovating a 1970's dormer bungalow which has had its cavities filled and roof insulated. It is in an exposed position, overlooking a valley and 23 metres long by 7 metres wide. We need a boiler to cope with the hot water for 3 showers - spread over the full length of the property, and may be used simultaneously, and also heat the house efficiently. Any suggestions?
Combi boiler will not work so either open or closed vent type and the latter is less likely to have problems with a low long house. You may need a circulation pump for domestic hot water and also extra bits to allow for expansion. Since non standard you will need good plumber and electrician the tables are only guides and too big of a boiler is not as much as a problem as too small but it will adversely effect control so any DIY calculations could cost more than they save.