Walchem’s online support is here to assist you with installation, troubleshooting tips, and training materials.

If you need additional support, please click here to locate your local master distributor. Walchem’s master distributors maintain a local inventory of pumps, controllers and spare parts, are fully trained to provide technical support and understand the needs of customers in their territories.

Trying to troubleshoot your W400 controller?
Print out or save to your phone for easy access!

Troubleshooting the Power Supply
Troubleshooting Boiler Controllers
ORP Sensor Troubleshooting
pH Sensor Troubleshooting

Here’s where you find general support documents for your W400 controller.
Print out or save to your phone for easy access!

Graphing Macro
Conductivity Sensor Cleaning
ORP Electrode Calibration Procedure
Chlorine Sensor Guidelines
Compatible USB Sticks
Disinfection Sensor Technical Tips
WEL Installation


Visit Walchem’s YouTube channel
for more technical support videos!