Combination boilers
There are specific requirements for the operation of domestic hot water combination boilers of nominal heat input not exceeding 70 kW for boilers, hot water boilers, gas-powered devices, hot-water central heating, central heating, hot-water supply systems, water supply.
Boilers are tested by BSI for temperature, domestic safety, fitness for purpose, leak tests, pressure testing, performance testing, thermal insulation, marking, instructions for use and energy conservation.