Atmospheric boiler is a non-pressurized hot water boiler, means that the top of the boiler is usually not subject to the static pressure of the water column of the heating system, equivalent to the "open hot water tank". It is an open system, the boiler body openings and the atmosphere, the main feature is that the boiler is not pressurized.

　　Pressurized boiler is what we usually see as a closed boiler. The vapor system in the boiler consists of closed containers and piping, which is subject to fluid pressure in operation and is a pressure vessel.

　　Both have certain applications in the market, and it is difficult for users to choose, so here we analyze the following seven aspects:

　　1/ atmospheric hot water boiler life is short, more security risks

　　Atmospheric boilers are generally handmade workshop-style small factory production, the main components of the boiler, such as the tube plate, barrel, furnace gall bladder, etc., is very thin, short life; these manufacturers do not have the ability to design and research and development, coupled with the lack of third-party inspection, resulting in no constraints on the processing requirements and acceptance, the quality of which is entirely dependent on the manufacturer's conscience, the boiler safety is not under control.

　　Once the system is not reasonably arranged, unauthorized openings connected to the atmosphere, connecting tube blocking, or installation of valves, will cause the boiler pressurized, more prone to safety accidents, hidden dangers.

　　The pressurized boiler belongs to special equipment, operating under pressure, high requirements in the design and processing, and is equipped with multiple interlocking protection, subject to the completion of the acceptance of the boiler inspection, the issuance of licenses before use, without violating the operation of the case, you can effectively avoid the safety risks.

　　2/The two system investment cost differences are not significant

　　Atmospheric boiler and pressurized boiler is mainly the difference between the price of the body, atmospheric boiler body with thin material, the body is relatively cheaper. In fact, the boiler is a systematic project, the boiler body is only part of it, under normal circumstances, the entire boiler room investment costs should not be much difference.

　　3 / atmospheric boiler energy-saving effect is poor High operating costs

　　The electric power of circulating water pump of atmospheric boiler is higher than that of pressurized boiler, and the operating energy consumption is large. Because the head of the circulating water pump of the atmospheric boiler not only to overcome the pipe resistance, but also to overcome the pressure difference with the heating system, while the pressurized boiler only needs to overcome the pipe resistance.

　　Atmospheric boiler is open type, the system stops, the system of circulating water will be due to the valve closure is not tight back to the boiler, so that the boiler over the water level, circulating water beyond the overflow pipe discharge, resulting in water loss of the system (discharged are hot water), restarted to replenish a large amount of cold water, resulting in unnecessary waste. In addition the open-ended system heat dissipation is also powerful.

　　4/ Pressurized boiler capacity range of hot water supply temperature wide

　　Pressurized hot water boilers can supply both high temperature and low temperature water, while atmospheric hot water boilers can only supply low-temperature water temperature less than 90 ℃, is not suitable for high-temperature heating system and high-rise building heating system.

　　In addition, "small and atmospheric hot water boiler safety supervision regulations" clearly stipulates that the rated thermal power of atmospheric hot water boiler should be less than or equal to 2.8MW, the capacity range is much lower than the pressurized boiler.

　　5 / atmospheric hot water boiler heating effect is poorer

　　In the same heating conditions, the same capacity of atmospheric hot water boiler can achieve the indoor heating temperature than the pressurized hot water boiler heating system is much lower, the heating effect is relatively poor, must be taken to low-temperature, long supply mode of operation.