Function of the pressure valve
1.When the air conditioner is short of refrigerant and the pressure is lower than 0.2Mpa
2.When the air conditioner pipe is blocked and the pressure is higher than 3.14Mpa
3.The pressure valve automatically cuts off the power to protect the compressor and pipes
Product parameters
1.Product name: high and low pressure switch/dual pressure switch
2.Model: SH-134a series
3.Protection range: customized according to customer needs
4.External thread diameter: 9mm and 11mm optional
5.Pin type: two pins
6.Application range: R134a air conditioning system

 Product Features
Using British pipe thread quick connector or copper pipe welding installation structure, it is easy to use, flexible to install, and does not require special installation and fixing. The plug-in type or wire type connection method can be selected by the user. Single-pole single-throw switch mode, normally open or normally closed switch contact structure can be selected at will. The welded sealed stainless steel pressure sensor and fully sealed switch structure are safe and reliable. The vacuum pressure value can reach as low as 15in.Hg (inches of mercury). Within the pressure range of 15in.Hg ~ 8PSI (-0.1 ~ 0.05MPa), the pressure value can be selected according to the user's requirements for manufacturing. The pressure parameters of the product have been set as required in the factory before leaving the factory, and no further setting is required, and it can be used directly.

Working Principle
This series of pressure controllers is mainly manufactured by using the built-in stainless steel reversible action diaphragm that can be reversed in the opposite direction after sensing a certain pressure. When the diaphragm moves, it will drive the electrical contacts to close or open through a guide rod. When the sensing pressure drops below the recovery value, the switch will automatically reset. Use
It is mainly used for the protection of low-pressure systems of various refrigeration equipment whose protection pressure value is negative pressure (lower than normal atmospheric pressure), and can also be used for the control of pneumatic, hydraulic, and lubricating oil systems. Design parameters
1.Working pressure range: 15in.Hg～8PSI (-0.1～0.05MPa)
2.Burst pressure: 2500PSI
3.Ambient temperature: -30℃～+80℃
4.System medium temperature: -50℃～+120℃
5.Life times under rated current: 30,000 times, 50,000 times, 100,000 times are available
6.Electrical specifications: 125VA for conventional electrical capacity at 24Vac, 375VA for conventional electrical capacity at 120/240Vac
7.Dielectric strength: AC700V/S between disconnected contacts, AC2000V/S between terminals and housing
8.Safe withstand voltage: The pressure that the pressure controller can withstand without affecting the action setting value.
Electrical schematic diagram

 Product Features
Using British pipe thread quick connector or copper pipe welding installation structure, it is easy to use and flexible to install, and no special installation and fixing is required. The plug-in type or wire type connection method can be selected by the user. The single-pole single-throw switch method, normally open type or normally closed type switch contact structure can be selected at will. The welded sealed stainless steel pressure sensor and the fully sealed switch structure are safe and reliable. The pressure value can be selected according to the user's requirements within the pressure range of 3 to 800PSI (0.02 to 5.5Mpa). The pressure parameters of the product have been set as required in the factory before leaving the factory, and no further setting is required, and it can be used directly.

How it works
This series of pressure controllers are mainly manufactured using the built-in stainless steel reversible action diaphragm that can flip in the opposite direction after sensing a certain pressure. When the diaphragm moves, it will drive the electrical contacts to close or open through a guide rod. When the sensing pressure drops below the recovery value, the switch will automatically reset. Application
This series of products is mainly used for high and low pressure protection control in refrigeration systems such as household, commercial, automotive air conditioners, ice makers, etc., and can also be used in various air compressors, equipment tools, and hydraulic and steam pressure control systems of agricultural machinery. Design parameters
1.Working pressure range: 3～800PSI (0.02～5.5MPa)
2.Burst pressure: 5000PSI
3.Ambient temperature: -30℃～+80℃
4.System medium temperature: -50℃～+120℃
5.Life times under rated current: 30,000 times, 50,000 times, 100,000 times are available
6.Electrical specifications: Conventional electrical capacity 125VA at 24Vac Conventional electrical capacity 375VA at 120/240Vac
7.Dielectric strength: AC700V/S between disconnected contacts, AC2000V/S between terminals and shell
8.Safe withstand voltage: The pressure that the pressure controller can withstand without affecting the action setting value.

 Product Features
Using British pipe thread quick connector or copper pipe welding installation structure, it is easy to use and flexible to install, and no special installation and fixing is required. The plug-in type or wire type connection method can be selected by the user. The single-pole single-throw switch method, normally open type or normally closed type switch contact structure can be selected at will. The welded sealed stainless steel pressure sensor and the fully sealed switch structure are safe and reliable. The pressure value can be selected according to the user's requirements within the pressure range of 3 to 800PSI (0.02 to 5.5Mpa). The pressure parameters of the product have been set as required in the factory before leaving the factory, and no further setting is required, and it can be used directly.

How it works
This series of pressure controllers are mainly manufactured using the built-in stainless steel reversible action diaphragm that can flip in the opposite direction after sensing a certain pressure. When the diaphragm moves, it will drive the electrical contacts to close or open through a guide rod. When the sensing pressure drops below the recovery value, the switch will automatically reset. Application
This series of products is mainly used for high and low pressure protection control in refrigeration systems such as household, commercial, automotive air conditioners, ice makers, etc., and can also be used in various air compressors, equipment tools, and hydraulic and steam pressure control systems of agricultural machinery. Design parameters
1.Working pressure range: 3～800PSI (0.02～5.5MPa)
2.Burst pressure: 5000PSI
3.Ambient temperature: -30℃～+80℃
4.System medium temperature: -50℃～+120℃
5.Life times under rated current: 30,000 times, 50,000 times, 100,000 times are available
6.Electrical specifications: Conventional electrical capacity 125VA at 24Vac Conventional electrical capacity 375VA at 120/240Vac
7.Dielectric strength: AC700V/S between disconnected contacts, AC2000V/S between terminals and shell
8.Safe withstand voltage: The pressure that the pressure controller can withstand without affecting the action setting value.
Electrical schematic diagram

Maximum working pressure range	Safety pressure resistance
<145PSI(1MPa)	250PSI(1.7MPa)
145PSI(1MPa)~400PSI(2.75MPa)	600PSI(4.1MPa)
>145PSI(2.75MPa)	800PSI(5.5MPa)

 Product Features
1.Adopt British pipe thread quick connector or copper tube (including capillary) welding connection structure, easy to install, can meet different needs. 2.The shell adopts two installation methods: board mounting (with mounting ears) or wire mounting (no need for additional fixing), which can be selected by users. 3.The sealed double insurance disc stainless steel sensor ensures that the switch connector is automatically and quickly disconnected under pressure, and cuts off the connection between the switch connector and the pressure in the system, ensuring that the system will not be damaged by accidentally turning on the switch to start the machine, which is particularly safe and reliable. 4.The independent automatic disconnection and manual reset dual structure design greatly improves the safety and reliability of pressure protection.

Working Principle
When the pressure in the system is higher than the rated safety pressure, the pressure sensing disc in the sensor will be activated instantly, and the push rod will push the safety disc to the locked position. At the same time, the safety disc will push the switch to disconnect through the connecting guide rod. When the pressure decreases, the sensing disc will automatically reset. Since the safety disc is already in the locked position, it cannot automatically reset and the switch cannot be turned on. Only when the external button is pressed and the safety disc is forced to unlock and the switch connector is connected, can the system return to normal working
Application
This series of pressure switches is suitable for various air conditioning and refrigeration systems with special requirements for pressure protection, and a wide range of occasions for overpressure protection of various equipment and tool pressure systems. The pressure switch can be directly installed on the pipeline, or installed on the equipment panel according to the equipment requirements.
Design parameters
1.Working pressure range: 145～800PSI (1～5.5MPa) 2.Burst pressure: 5000PSI 3.Ambient temperature: -30℃～+80℃ 4.System medium temperature: -50℃～+120℃ 5.Electrical specifications: Conventional electrical capacity 125VA at 24Vac, conventional electrical capacity 375VA at 120/240Vac 6.Dielectric strength: AC700V/S between disconnected contacts, AC2000V/S between terminals and housing 7.Safe withstand voltage: The pressure that the pressure controller can withstand without affecting the action setting value. Electrical schematic diagram

Maximum working pressure range	Safety pressure resistance
145PSI(1MPa)~400PSI(2.75MPa)	600PSI(4.1MPa)
>400PSI(2.75MPa)	800PSI(5.5MPa)

 Product Features
1.Adopt British pipe thread quick connector or copper pipe welding structure, easy to use, flexible installation, no special installation and fixing required;
2.Insert type or wire type connection mode is available for users to choose;
3.Single-pole single-throw switch mode, normally open switch contact structure;
4.Fusion-welded sealed stainless steel pressure sensor plus steel explosion-proof shell, safe and reliable;
5.In the pressure range of 1305PSI~2610PSI (9~18MPa), the pressure value can be selected according to the user's requirements for manufacturing;
6.The pressure parameters of the product have been set as required in the factory before leaving the factory, no need to set again, can be used directly;

Working Principle
This series of pressure switches is mainly manufactured by using the built-in stainless steel reversible action diaphragm that can be flipped in the opposite direction after sensing a certain pressure. When the diaphragm moves, it will drive the electrical contacts to open through a guide rod. When the sensing pressure drops below the recovery value, the pressure switch can automatically reset.
Application
This series of products is specially designed and manufactured for refrigeration equipment using carbon dioxide as a refrigerant. The refrigeration system pressure is much higher than the conventional refrigerant pressure. It is used for high-pressure protection of the system; it is also suitable for various types of equipment and tools with high-pressure protection pressure greater than 800PSI (5.5MPa).
Design parameters
1.Working pressure range: 1305~2610PSI (9~18MPa)
2.Burst pressure: 10440PSI (72MPa)
3.Ambient temperature: -30℃～+80℃
4.System medium temperature: -50℃～+120℃
5.Electrical specifications: Normal electrical capacity 125VA at 24Vac Normal electrical capacity 375VA at 120/240Vac
6.Dielectric strength: AC700V/S between disconnected contacts, AC2000V/S between terminals and housing
Electrical schematic diagram