Can the outlet temperature of a atmospheric-pressure hot water boiler be set at 98°C?

The regulations stipulate that the angle must not exceed 90 degrees. This is specified in the “Notice on Issues Related to the Implementation of the Provisions on Safety Technical Inspection of Small and Atmospheric Pressure Hot Water Boilers”, as follows: [Title of Regulation] Notice on Issues Related to the Implementation of the Provisions on Safety Technical Inspection of Small and Atmospheric Pressure Hot Water Boilers [Issuing Authority] **General Administration of Quality Supervision, Inspection and Quarantine** [Document Number] [Issuance Date] 2002-5-20 [Expiration Time] 0:00:00 [Full Text] Notice on Issues Related to the Implementation of the Provisions on Safety Technical Inspection of Small and Atmospheric Pressure Hot Water Boilers **General Administration of Quality Supervision, Inspection and Quarantine** General Administration of Quality Supervision, Inspection and Quarantine, Guo Jian Zhi Guo Han [2002] No. 288 Notice on Issues Related to the Implementation of the Provisions on Safety Technical Inspection of Small and Atmospheric Pressure Hot Water Boilers To the Quality and Technical Supervision Bureaus of all provinces, autonomous regions, and municipalities directly under the Central Government: In order to better implement the Provisions on Safety Technical Inspection of Small and Atmospheric Pressure Hot Water Boilers (formerly Order No. 11 issued by the **Quality and Technical Supervision Bureau, hereinafter referred to as the “Provisions”), the following points regarding issues that arise during implementation are clarified as follows: I. Regarding whether tea boilers fall under the scope of safety inspection Tea boilers refer to devices that use coal, gas, fuel oil, or electricity for heating, and are designed specifically for producing boiling water. The tea water boiler shall be equipped with an opening or pipe leading directly to the atmosphere at the top of the boiler body, and this opening or pipe must remain unobstructed; no water seal shall be installed. Tea water boiler manufacturers shall spray a warning label stating “Not pressurized” in a prominent position on the boiler body. Tea boilers that meet the above conditions fall outside the scope of application of the Regulations; they do not require a boiler manufacturing license, nor is there any need for registration procedures for their use, and operators are not required to obtain certification through the assessment regulations for boiler operators. 　　II. Regarding the issue of whether domestic water heating and coal stoves should be included in safety inspections: Domestic water heating and coal stoves were developed in China over the past decade or so, and their annual production volume has now reached 2.5 million units. The product features a jacketed design and is manufactured in accordance with the **standard GB/T16154-1996. The relevant departments have now completed the revised draft for approval of this standard, which specifies that the requirements related to safety are mandatory provisions; these mainly include: rated heating capacity < 50 KW ； The working pressure comes from the water supply pressure ； The outlet water temperature shall not exceed 85℃ ； An explosion-proof disc is installed on the furnace body ； Warning messages and the like are sprayed in prominent locations on the furnace body. Civil water heating and coal stoves that meet the above requirements fall outside the scope of application of the Regulations; they do not require a boiler manufacturing license, nor are registration procedures necessary, and the operators are not required to obtain certification through the Assessment and Management Regulations for Boiler Operators. 　　III. Issues regarding the classification of gas water heaters (including rapid-type and volume-type types), electric water heaters, as well as gas boilers and electric heating boilers. In China, gas water heaters are divided into rapid-type and volume-type categories, and they are designed and manufactured in accordance with the two mandatory standards, namely \"Rapid-Type Domestic Gas Water Heaters\" (GB6932-2001) and \"Volume-Type Gas Water Heaters\" (GB18111-2000). Electric water heaters are designed and manufactured in accordance with the standard GB4706.12-1995 \"Special requirements for storage-type electric water heaters used in household and similar applications\". After consultation with the relevant departments, the scope of gas or electric water heaters should be such that their rated thermal power is less than 0.1 MW ； The working pressure comes solely from the water supply pressure ； The maximum water capacity shall not exceed 500L ； The outlet water temperature should not exceed 90℃ ； It is equipped with a reliable temperature control device, automatic protection systems against over-temperature and over-pressure, as well as an automatic protection system for low water levels; in the event of any abnormalities, the heat source is automatically shut off ； Gas water heaters should also be equipped with an automatic gas cut-off protection device. Water heaters that meet the aforementioned requirements as well as the standards GB6932-2001, GB18111-2000, and GB4706.12-1995 are not considered boilers; therefore, they fall outside the scope of application of these regulations. They do not require a manufacturing license for boilers, nor do they need to go through registration procedures for use. There is no need to build a separate boiler room for them, nor are operators required to obtain certification in accordance with the regulations regarding the assessment of boiler operators. 　　IV. Regarding the issue of whether small steam boilers require a separate boiler room Small steam boilers refer to those with a water capacity of no more than 50L and a rated steam pressure of no more than 0.7MPa. If fuel, gas, or electric heating is used, there must be reliable temperature control devices, as well as automatic protection systems against over-temperature and over-pressure conditions, along with low-water-level protection devices. In the event of any abnormalities, the heat source can be automatically shut off. It is not necessary to build a separate boiler room, but it should be separated from the areas where steam is used. During installation, it is important to ensure that the discharge direction of the safety valves does not point toward areas where people are present. 　　V. Issues regarding the prevention of pressurized use of atmospheric-pressure hot water boilers 　At present, explosions involving atmospheric-pressure hot water boilers occur frequently, and the reason for this is their use under pressure. To prevent atmospheric pressure hot water boilers from being used under pressure, our agency requires that all manufacturers of such boilers install openings or connections that lead directly to the atmosphere at the top of the boiler’s vessel. These openings or connections must remain unobstructed; no water seals are allowed. In addition, a warning label stating “This is an atmospheric pressure boiler and must not be used under pressure; the temperature of the hot water exiting the boiler shall not exceed 90°C” must be applied in a visible location on the boiler’s vessel. Warning signs should also be added to the operating atmospheric-pressure hot water boilers. In the future, for newly manufactured atmospheric pressure hot water boilers that do not have openings or connections leading directly to the atmosphere at the top of the boiler body, nor do they have the aforementioned warning markings applied to them, the manufacturing company will have to assume corresponding responsibility in the event of an accident, including legal liability for failing to inform users and installers about safety matters. Atmospheric pressure boilers that do not meet the regulations should be investigated and dealt with in accordance with the law in various regions. 　　VI. Management of Vacuum Phase-Change Boilers Vacuum phase-change boilers do not experience explosion accidents because the pressure in their fluid circulation system is lower than atmospheric pressure. Manufacturing enterprises shall produce vacuum phase-change boilers in accordance with standards, and bear the legal responsibility to inform users (including those who install the boilers) on safe usage, ensuring that the boiler system remains in a vacuum state at all times during use. The installation unit of the vacuum phase-change boiler is responsible for ensuring that the installation quality meets the requirements specified by the manufacturer. Vacuum phase-change boilers that meet the above requirements do not need to be verified by the boiler and pressure vessel safety supervision agencies under the quality and technical supervision authorities after installation, nor do they require registration for use. 　　This is to inform you. May 20, 2002

To prevent vaporization and for safety reasons, the designed outlet temperature for low-pressure hot water boilers is 95 degrees, with a return water temperature of 70 degrees; for atmospheric-pressure hot water boilers, the outlet temperature is 85 degrees and the return water temperature is 60 degrees.

It’s not possible, because if the outlet temperature of a atmospheric pressure boiler is too high, vaporization will occur. This will cause problems with the water pump, as the pump in an atmospheric pressure hot water boiler is used to draw hot water from the boiler and supply it to the system. Therefore, the temperature cannot be set too high; the specified limit is 85 degrees.

If the temperature setting is incorrect or the thermometer is inaccurate, the boiler overpressures.