FS8-W has a weatherproof NEMA 4X housing; FS7-4 has SPDT switch, 1-1/4 in. process connection and is for larger pipes 6 in. to 16 in. FS7-4W is the same as the FS7-4 except with weatherproof NEMA 4X housing; more information & related documents . Series Description.. 120601 McDonnell & Miller FS8-W - 1" Flow Switch General purpose flow switch w/NEMA 4X enclosure 120601. Mcdonnell & Miller 120601 Instruction Manual. For general purpose applications with environmental exposure, or those requiring a water-tight, dust tight, or a NEMA 4X rated flow switch.
McDonnell & Miller Series FS8-W Flow Switches Parts; McDonnell & Miller Replacement Parts List; Diagrams. Repair Parts. Repair Parts. Check items to add to the cart or select all. Add to Cart. McDonnell & Miller FS4-15SS Stainless Steel Paddle Kit (310451) List Price $39.00 $29.88 / each.. Find out how to use McDonnell & Miller Series FS8-W General Purpose Liquid Flow Switches for steam boilers and other applications. These switches are water-tight, dust tight, and NEMA 4X rated, with four paddle sizes and sensitivity adjustment.