It is measured in kilowatts (kW) and depends on how many radiators, showers and bathrooms that you have. For one bathroom, look out for 26kW at minimum, 30kW for two, 35kW for three, while larger ...

Best combi boilers to keep you toasty this winter ... 30kW for two, 35kW for three, while larger homes with more than three ...

Your 30kw combi boiler, by comparison, should cost £2.06 to run your central heating for one hour, assuming you are paying 6.24p per/kWh for gas at price-capped rates and your boiler is 90 per ...