Honeywell Aquastat Controller, Breaks on Rise, 120 to 240 VAC/0.25 to 12 VDC, 100 to 240 deg F, 5.1 to 48 A, Horizontal/Vertical Mount, 3/8 x 2-7/8 in Copper Bulb, Micro Switch" Snap-Acting Switch
Aquastat® Controllers are immersion type devices for limiting or regulating the temperature of liquids in boilers, storage tanks and other applications where temperature control is required. Honeywell's L4006 are used in applications that utilize the existing wells.