Heat gun with chimney Indirectly fired heat gun with chimney. Delivers reliable heat with an efficiency of 87%. Suitable for construction sites in the cold season, stables with good ventilation or to keep machinery, vehicles and pipelines free of ice. Danfoss® pump, built-in room thermostat, overheating thermostat, electronic flame protection, stainless steel combustion chamber, fully automatic aftercooling, integrated fuel tank.