The lower parts of the boiler body (consist of combustion chamber and heat transfer tubes) is the same as ordinary hot water boiler. The upper part of the boiler body is equipped with heat exchanger and expansion water tank. The water level inside the tank is controlled automatically.

The whole part of the boiler is operated under the condition of atmospheric pressure which makes the operation safe and reliable. The heat exchanger are conducted between hot media water and heat exchanger. The hot media water are totally softened and deoxidized without any corrosion and water scale to extend boiler working life.

Heat exchangers made by special processed stainless steel or copper are equipped inside the boiler to increase the heat exchange efficiency and achieve quick temperature rise of water.