Walchem EWN-R Metering Pump

The EWN-R Series electronic metering pumps offer superior high speed dosing capability with more standard features. The flexibility of the EWN-R pump enables it be integrated into virtually any chemical feed application using a universal-voltage, digital controller with an expanded set of control features.

Superb valve performance and advanced solenoid engineering combine to make a precision pump, suitable for the most demanding applications. EWN metering pumps have outputs to 6.7 GPH (25.2 L/h) and a maximum pressure of 250 PSI (17 bar). The high speed of operation results in high resolution chemical feed and long service life. Quiet and compact, the EWN pump primes in seconds and holds prime reliably.

Walchem EWN-R Electronic Metering PumpHigh Speed Performance

E-Series pumps operate up to 360 strokes-per-minute with adjustments in 1 spm increments, providing high resolution chemical feed. Adjustable stroke length further increases the ability to refine output, making the E-Series one of the most versatile solenoid metering pumps on the market.

Multi-function Digital Controller

The controller in the EWN-R metering pump provides for flexible pump control including scalable Analog control, Digital Input with both Multiply and Divide capability, external stop control, or simple speed and stroke length control. Display can be adjusted between flow rate units or % speed for easy-to-read output and quick adjustment. The controller is universal voltage so it can be used anywhere in the world.

Engineered Longevity

All E-Series pumps feature dual bearing support. The armature and shaft are supported with a bearing on each end, which ensures proper axial movement, enabling the E-Series to operate at 360 SPM while extending the life of the diaphragm.

Walchem EWN-R Metering Pump

Quiet and compact, the EWN pump primes in seconds and holds prime reliably.

Superior Check Valve Performance

Dual Check Valve Assemblies in both the suction and discharge fittings feature precision ball guides and tapered seats. Precise machining and molding of parts limit valve ball travel, ensuring that balls fully seat and seal with every stroke. This superior check valve design guarantees fast priming and reliable performance.

Flexible Connections

A removable tubing insert provides flexibility of tubing sizes and eliminates twisting of the tubing during connection. A threaded insert can be used in place of the tubing adapter to easily convert any connection to NPT.

High Compression Ratio

The compression ratio of a metering pump is important because it affects the pump’s ability to prime and vent. The compression ratio is raised when you reduce the dead volume of the pump head during operation. All E-Series pumps feature a very high compression ratio that ensures proper feed especially with off-gassing products (i.e. Sodium Hypochlorite).


For complete information on the EWN-R pump, or for assistance selecting the correct pump for your specific application, please call our Ryan Herco Customer Service experts at 800-848-1141 today.

Link: Walchem EWN-R Pump Data Sheet