Introduction
This instruction manual provides essential information for the safe and efficient installation, operation, and maintenance of the Danfoss EV251B Solenoid Valve. Please read this manual thoroughly before attempting any installation or operation procedures. Retain this manual for future reference.
Safety Information
Always observe general safety precautions when working with electrical and pressurized systems. Failure to follow these instructions may result in property damage, serious injury, or death.
- Ensure power supply is disconnected before installation, maintenance, or repair.
- Verify that the valve specifications match the system requirements.
- Installation and service should only be performed by qualified personnel.
- Wear appropriate personal protective equipment (PPE).
- Do not exceed the maximum operating pressure or temperature specified for the valve.
Product Overview
The Danfoss EV251B is a 2/2-way assisted lift operated solenoid valve designed for various industrial applications. It features a G1 outlet connection type and an NBR seal, suitable for specific media and temperature ranges. The valve operates on a 230V, 50Hz power supply.
Figure 1: Danfoss EV251B Solenoid Valve. This image displays the brass valve body with a blue solenoid coil attached to the top. A black square gasket and a screw are shown in the foreground, indicating components for assembly or sealing.
Specifications
| Model | EV251B |
| Part Number | 032U538331 |
| Type | 2/2-way, Assisted Lift Operated |
| Orifice Size | 7/8 inch |
| Connection Type | G1 (Outlet) |
| Seal Material | NBR (Nitrile Butadiene Rubber) |
| Voltage | 230V AC |
| Frequency | 50Hz |
| Brand | Danfoss |
| Manufacturer | Kempston Controls |
| ASIN | B07HCDVTQN |
Setup and Installation
1. Pre-Installation Checks
- Inspect the valve for any signs of damage during shipping.
- Ensure the system is depressurized and drained before installation.
- Verify that the flow direction arrow on the valve body matches the system flow.
2. Mounting
- Mount the valve in a position that allows for easy access for maintenance.
- Ensure the valve is installed vertically with the coil pointing upwards for optimal performance, unless otherwise specified for specific applications.
- Use appropriate pipe sealant on threaded connections to prevent leaks. Do not overtighten.
3. Electrical Connection
- Ensure the power supply matches the coil voltage (230V AC, 50Hz).
- Connect the electrical wiring according to local electrical codes and the wiring diagram provided with the coil.
- Secure all electrical connections to prevent accidental disconnection or short circuits.
Operating Instructions
The Danfoss EV251B is an assisted lift operated valve. This means it requires a minimum pressure differential to fully open or close, but can operate from zero differential pressure due to the assisted lift mechanism. When the coil is energized, the valve opens, allowing fluid flow. When de-energized, the valve closes, stopping flow.
- Initial Start-up: After installation, slowly pressurize the system and check for leaks.
- Operation: Apply the rated voltage to the coil to open the valve. Remove voltage to close the valve.
- Flow Control: This valve is designed for ON/OFF control and is not intended for throttling applications.
Maintenance
Regular maintenance ensures optimal performance and extends the lifespan of the valve. Always de-energize the coil and depressurize the system before performing any maintenance.
1. Cleaning
- Periodically inspect the valve for external dirt or debris. Clean with a soft cloth.
- If internal cleaning is required, disassemble the valve carefully, clean components with appropriate solvents compatible with NBR seals, and reassemble.
2. Inspection
- Check for leaks around connections and the valve body.
- Inspect the coil for signs of overheating or damage.
- Examine the NBR seals for wear, cracks, or degradation. Replace if necessary.
Troubleshooting
| Problem | Possible Cause | Solution |
|---|---|---|
| Valve does not open | No power to coil; Incorrect voltage; Coil failure; Obstruction in valve. | Check power supply and connections; Verify voltage; Replace coil; Inspect and clean valve internals. |
| Valve does not close | Debris preventing closure; Worn seal; Coil remains energized. | Clean valve internals; Replace seal; Check electrical circuit for continuous power. |
| Leakage from valve | Loose connections; Damaged seals; Cracked valve body. | Tighten connections; Replace seals; Replace valve if body is cracked. |
Warranty Information
Danfoss products are manufactured to high-quality standards. This product is covered by a standard manufacturer's warranty against defects in materials and workmanship. The specific terms and duration of the warranty may vary by region and purchase date. Please refer to your purchase documentation or contact Danfoss customer support for detailed warranty information.
Customer Support
For technical assistance, spare parts, or further inquiries regarding your Danfoss EV251B Solenoid Valve, please contact your local Danfoss representative or visit the official Danfoss website. Ensure you have the model number (EV251B) and part number (032U538331) available when seeking support.
You can find more information and contact details on the Danfoss Store.
