1. Convenient operation. For hot water boilers, it is water that flows in and out. Except the steam and water both usedboiler, you only need to monitor the boiler’s pressure and the temperature of outlet water and return water. Don't need to monitor the liquid level.

　　2. When the hot water boiler power off or pump power off , the pot water is easy get vaporize. Measures must be taken to ensure the boiler runs safe and reliable.

　　3. The temperature of hot water boiler working medium is lower than the steam, which is lead to acid corrosion of the flue gas side. The design of boiler’s tail should avoid the water temperature of heating surfaces is too low.

　　4. The Utilization of hot water boiler used for heating is low, so the hot water boiler should have features of convenient maintenance,low cost. Hot water boiler and steam boiler is no fundamental difference in the structure. Their design method and form of combustion chamber are similar.

　　5. The requirement of water quality is relatively low, high safety. Water does not evaporate in the boiler, so scaling is less than steam boiler. Water treatment is to remove the oxygen and temporary hardness.

　　6. Due to the heating by hot water boiler is seasonal, so the heat quantity required has much to do with season, environment, temperature. The boiler design should let the heating load adjustable and adapt large heat load in order to ensure the boiler can long-term work under stable condition and the combustion efficiency.

　　7. DC hot water boiler can without drum, simple structure, easy fabrication, and simple manufacturing process, low steel consumption, low cost .

　　8. The heat temperature and pressure of hot water boiler is high. Hot water boiler save steel compared with steam boiler.

　　9. Easy to stick ash. Most hot water boilers are used for heating in China. And they are operated unreasonably intermittently. When boiler starts, the temperature of metal wall is low, the tail heating surface is easy to condense and easy to stick ash.