1. Introduction
This manual provides essential information for the safe and efficient installation, operation, and maintenance of your Baomain HV-03 Rotary Lever Hand Valve. Please read this manual thoroughly before using the product to ensure proper function and to prevent damage or injury.
2. Safety Information
- Always ensure the pneumatic system is depressurized before installation, maintenance, or removal of the valve.
- Wear appropriate personal protective equipment (PPE) such as safety glasses.
- Do not exceed the maximum operating pressure specified for the valve.
- Ensure all connections are secure and leak-free to prevent unexpected air release.
- Use only filtered compressed air as the working medium.
3. Product Overview
The Baomain HV-03 is a 3-position, 4-way rotary lever hand valve designed for controlling the direction of pneumatic air flow in various industrial and scientific applications. It features a robust metal construction and a manual lever for precise control. The valve is of the 'midst closed type', meaning that in the center position, all ports are blocked, stopping air flow to the output ports.

Image 3.1: Overview of the Baomain HV-03 Rotary Lever Hand Valve. This image displays the valve from an angled perspective, showing the main body, the rotary lever with a black handle, and the various connection ports.
Key Features:
- Model: HV-03
- Working Medium: Filtered Compressed Air
- Type: 3 Position 4 Way, Midst Closed
- Port Size: PT3/8"
- Effective Area: 16mm²
- CV Value: 0.89
- Operating Pressure: 0-10 kg/cm² (0-1000 kPa / 0-10 bar)
- Valve Size: 150 x 72 x 87mm (5.9" x 2.8" x 3.4")
- Net Weight: 428g (1.06 pounds)
- Material: Metal
4. Components
The HV-03 valve consists of the main valve body, a rotary lever with a handle, and various threaded ports for air connections. It typically includes a muffler for exhaust and push-to-connect fittings for tubing.

Image 4.1: Baomain HV-03 valve with included accessories. This image shows the main valve body, a separate muffler, and three push-to-connect fittings, all labeled with their respective sizes (3/8" and 8mm).
5. Setup and Installation
Follow these steps for proper installation of the HV-03 valve:
- Mounting: Securely mount the valve to a stable surface using appropriate fasteners through the mounting holes. The installing hole diameter is 5mm (0.2").
- Port Identification: Identify the input (P), output (A and B), and exhaust (R and S, often combined with muffler) ports. Refer to the diagram in the Operating Instructions section for port labeling.
- Air Supply Connection: Connect the filtered compressed air supply line to the 'P' (Pressure/Input) port. Ensure a tight, leak-free connection using PT3/8" fittings.
- Output Connections: Connect your pneumatic actuators or devices to the 'A' and 'B' (Output) ports.
- Exhaust Connection: The valve has exhaust ports (often labeled R and S, or combined with a muffler). Install the provided muffler or an appropriate exhaust line to these ports to reduce noise and prevent contamination.
- Leak Check: After all connections are made, slowly pressurize the system and check for any air leaks using a leak detection solution. Tighten connections as necessary.
6. Operating Instructions
The HV-03 is a 3-position, 4-way valve, meaning it has three distinct lever positions that control the flow of air to two output ports (A and B) from a single input port (P), with two exhaust ports (R and S, or muffler). The 'midst closed' design ensures that in the center position, all ports are blocked.

Image 6.1: Diagram showing the port connections and air flow direction for the Baomain HV-03 valve. The image labels P(IN) for pressure input, A(OUT) and B(OUT) for output ports, and P(MUFFLER) for the exhaust port.
Lever Positions:
- Position 1 (Lever to one side): Air flows from P to A, and B exhausts. This typically extends a cylinder or activates one side of a device.
- Position 2 (Center/Midst Closed): All ports (P, A, B, exhaust) are blocked. Air flow stops, and any connected actuators will hold their position.
- Position 3 (Lever to the other side): Air flows from P to B, and A exhausts. This typically retracts a cylinder or activates the other side of a device.
To operate, simply move the rotary lever to the desired position to control the air flow. Ensure smooth and deliberate movements of the lever.
7. Maintenance
Regular maintenance ensures the longevity and reliable operation of your HV-03 valve.
- Inspection: Periodically inspect the valve for any signs of wear, damage, or corrosion. Check the lever for smooth operation.
- Leak Detection: Regularly check all connections for air leaks. Even small leaks can lead to energy waste and reduced system performance.
- Air Quality: Ensure the compressed air supply is clean and dry. Contaminants can cause internal damage and reduce valve lifespan. Replace air filters as recommended by your compressor manufacturer.
- Cleaning: If necessary, clean the exterior of the valve with a damp cloth. Do not use harsh chemicals or solvents that could damage the material.
- Lubrication: The valve is designed for use with lubricated air. Ensure your air supply system provides adequate lubrication if required by your overall pneumatic setup.
8. Troubleshooting
Refer to the table below for common issues and their potential solutions:
| Problem | Possible Cause | Solution |
|---|---|---|
| No air flow from output ports | No air supply; Valve in midst closed position; Blocked input port; Internal blockage | Check air supply pressure; Move lever to an active position; Inspect input line for obstructions; Disassemble and clean (if qualified) |
| Reduced air flow | Low air supply pressure; Partial blockage in lines or valve; Worn internal seals | Check air supply pressure; Inspect lines and ports for debris; Consider valve replacement if seals are worn |
| Air leaks from connections | Loose fittings; Damaged threads; Incorrect sealant; Worn O-rings/seals | Tighten fittings; Replace damaged fittings; Apply appropriate thread sealant; Replace O-rings/seals |
| Lever difficult to move | Lack of lubrication; Internal contamination; Mechanical damage | Ensure air supply is lubricated (if applicable); Clean valve internals; Inspect for physical damage |
9. Specifications
Detailed technical specifications for the Baomain HV-03 Rotary Lever Hand Valve:

Image 9.1: Dimensional drawing of the Baomain HV-03 valve. This image provides key measurements in both inches and millimeters for the valve's length, width, height, and port sizes.
- Model: HV-03
- Working Medium: Filtered Compressed Air
- Type: 3 Position 4 Way, Midst Closed
- Port Size: PT3/8" (G Connector)
- Effective Area: 16mm²
- CV Value: 0.89
- Operating Pressure: 0-10 kg/cm² (0-1000 kPa / 0-10 bar / 0-145 PSI)
- Maximum Operating Pressure: 1000000 Pascal (10 bar)
- Number of Ports: 4
- Material: Metal
- Valve Size (L x W x H): 150 x 72 x 87 mm / 5.9 x 2.8 x 3.4 inches
- Installing Hole Diameter: 5mm / 0.2 inches
- Item Weight: 1.06 pounds (428g)
- Package Dimensions: 4.13 x 3.11 x 3.11 inches
- Manufacturer: Baomain Electric Co.,Ltd
- UPC: 711811413582
- ASIN: B01ITNOZIW
- Specification Met: ASME, ASTM, MSS SP 72, MSS SP 80, CE
10. Warranty and Support
For warranty information, technical support, or service inquiries regarding your Baomain HV-03 valve, please contact Baomain Electric Co.,Ltd directly through their official channels or the retailer from whom the product was purchased. Please have your model number (HV-03) and purchase details available when contacting support.





