When it comes to efficient and safe system control in industrial operations, few components are as essential as a pressure switch. These small but powerful devices provide automatic control, monitoring, and protection in fluid and air pressure systems. Among the top choices in the market, Lefoo pressure switches stand out for their reliability, flexibility, and durability across multiple industries.
In this post, we explore 5 practical applications of Lefoo pressure switches, with real-world examples that highlight how these devices are integrated into hydraulic systems, air compressors, water pumps, HVAC systems, and reverse osmosis water purifiers. Whether you're an engineer, technician, or systems designer, understanding how and where pressure switches are applied can help optimize your installations.
A pressure switch is an electromechanical device that detects changes in pressure and activates or deactivates electrical contacts based on preset thresholds. Its primary function is to automatically start or stop equipment such as pumps, compressors, or fans when the system pressure reaches a certain level.
Lefoo offers a wide range of pressure switches with customizable set points, housing materials, and connection types — suitable for various pressure ranges and media.
Lefoo pressure switches are:
Reliable: High-performance materials and strict quality standards
Customizable: Factory preset or adjustable ranges available
Versatile: Suitable for air, water, oil, refrigerants, and other fluids
Compact: Designed to fit into tight installations
Cost-effective: Affordable without compromising performance
Popular models include:
LF17-W: Water pressure switch
LF19: Air compressor pressure switch
LF20: HVAC pressure switch
LF55/LF58: Reverse osmosis system switches
One of the most common and critical applications of pressure switches is in automatic water pump systems. The Lefoo LF17-W water pressure switch is specially designed to control household or commercial pumps based on water pressure in the system.
When the water pressure drops below a set minimum (e.g., 20 psi), the switch closes the circuit, turning the pump ON. When the pressure reaches the upper limit (e.g., 40 psi), it opens the circuit and turns the pump OFF.
Protects the pump from dry running
Ensures stable water pressure for faucets and appliances
Reduces energy consumption by avoiding continuous operation
Residential water tanks
Garden irrigation systems
Booster pump control in commercial buildings
In compressed air systems, maintaining consistent pressure is vital for performance and safety. The Lefoo LF19 pressure switch is widely used to manage air compressors in garages, factories, and workshops.
The LF19 monitors the tank pressure and automatically starts or stops the compressor to maintain preset levels. This prevents over-pressurization and reduces motor wear.
Built-in unloader valve options
Compact design for easy integration
Available with manual on/off lever
Pneumatic tool systems
Tire inflation stations
Industrial compressors and dryers
Heating, ventilation, and air conditioning (HVAC) systems require accurate pressure control to maintain efficiency and safety. The Lefoo LF20 pressure switch is ideal for air conditioning units and refrigerant systems.
Suitable for R134a, R22, R410A refrigerants
Snap-action contacts for rapid response
Compact, hermetically sealed housing
Preventing overpressure in cooling systems
Monitoring refrigerant pressure in split ACs
Ensuring compressor cut-off in commercial refrigeration
Using the LF20 ensures optimal temperature control, avoids refrigerant leaks, and prolongs equipment lifespan.
In reverse osmosis (RO) systems, pressure switches play a critical role in automation and safety. The LF55 and LF58 switches from Lefoo are designed to detect feed water pressure and control the booster pump accordingly.
When water supply pressure drops below a minimum level, the switch stops the pump to prevent damage or dry running. It also ensures the RO membrane functions only under ideal pressure conditions.
Extends membrane life
Prevents pump burnout
Enables automatic shut-off in tank-full conditions
Residential RO systems
Commercial water purifiers
Under-sink water filtration units
Hydraulic systems rely on consistent fluid pressure to operate cylinders, motors, and actuators. Lefoo pressure switches can be installed to monitor system pressure and provide critical control functions, such as:
Triggering alarms if pressure drops
Activating secondary systems
Preventing overload by cutting off the pump
In lubrication systems, a pressure switch ensures oil or grease is properly delivered to components like bearings or gears. If pressure falls outside safe limits, the switch alerts the controller to stop the machine and avoid damage.
Manufacturing and assembly lines
CNC machinery
Injection molding systems
Food and beverage production
To get the best performance from your Lefoo pressure switch, consider the following:
| Selection Criteria | Considerations |
| Pressure Range | Ensure it matches the system’s operating pressure |
| Media Compatibility | Choose materials suited for water, oil, air, or refrigerant |
| Mounting Type | Inline, panel-mount, or threaded connections |
| Electrical Ratings | Voltage and current capacity of the switch contacts |
| Adjustability | Some models offer factory preset, others allow field adjustment |
All Lefoo switches are built under ISO 9001 standards and offer CE/RoHS compliance for international markets.
From water pumps to air compressors and HVAC systems, Lefoo pressure switches provide an affordable and efficient solution for industrial and residential pressure control needs. Their adaptability across applications, reliable operation, and robust build make them a trusted choice worldwide.
By integrating pressure switches into your systems, you gain:
Better automation
Increased system protection
Reduced maintenance costs
Improved energy efficiency
Explore the full range of pressure switches at www.lefoo.com and contact our technical team for application support or custom configurations.
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