The Walchem WMB81100-1NNNN controller is now obsolete and the closest equivalent is the WBL600PSSNN-AA controller. The new series has upgraded features; for reference, here is the description of the old model:
Multi I/O boiler controller, contacting electrode 1: 250 PSI, contacting electrode 2: 250 PSI, no conductivity sensor - boiler 3, no conductivity sensor - boiler 4, prewired w/ USA cords, 7 powered relays, 1 dry contact relay, no analog outputs, 6 digital inputs, USB & Ethernet comms software/hardware, no add'l comms hardware, no add'l comms software.
Choose the new model on our WBL600PSSNN-AA page or select a model more suited to your needs from our WBL600 or WBL900 pages.
