The Clack WS1EE is a twin alternating control valve from the Water Specialist line, used as the control head on twin-tank softener and filter systems. In a twin alternating configuration one tank stays in service while the other regenerates, so treated water remains available continuously rather than being interrupted during a regeneration cycle. The valve's front panel indicates which tank is in service.
Control is by solid state microprocessor with settings accessible from the front panel. The display reports time of day, days until the next regeneration, volume remaining, current flow rate, and total volume used. Regeneration can be initiated by any of four methods — meter immediate, meter delayed, time clock delayed, or pressure differential — and the six-cycle sequence covers backwash, downflow brining and slow rinse, a second backwash, fast rinse, regenerant refill, and downflow service, each with adjustable cycle times. An optional double backwash feature is available. A coin cell lithium battery provides approximately eight hours of carryover.
The valve body is fiber reinforced composite and regeneration is downflow. Service flow is rated at 28 gpm at a 15 psi drop with bypass and meter installed, and backwash flow at 15 gpm at a 25 psi drop with bypass. It operates between 20 and 125 psi and between 40 and 110 °F. The integral meter is accurate to plus or minus 5 percent over a 0.25 to 30 gpm range. Power is supplied through a Level VI 15 volt DC power supply, available in US and international supply voltages.
The valve mounts on a 2-1/2 inch to 8 NPSM base and accepts inlet and outlet fittings from 3/4 inch to 1.5 inch NPS. It supports softener tanks from 6 to 21 inches in diameter and filter tanks from 6 to 16 inches in diameter. Clack offers backwash filter, bypass, and weather cover options. The valve is certified to NSF/ANSI 44 and to NSF/ANSI/CAN 61 and 372.
