Ключевые слова:
Boilers, Steam condensers, Heaters, Heating equipment, Hot-water boilers, Domestic, Central heating, Gas-powered devices, Design, Condensation, Combustion products, Temperature, Efficiency, Testing conditions, 1st family gases, 2nd family gases, 3rd family gases, Marking, Instructions for use, Installation, Performance testing, Hot-water central heating, Gas space heating, Formulae (mathematics), Error correction, Classification systems, Rated power