Caleffi 519 Series 519700A Differential Pressure By Pass Valve With Graduated Scale, 1-1/4 x 1-1/4 in, Up to 45 gpm

The differential pressure by-pass valve is used in systems with a fixed speed circulating pump supplying several zones controlled by two way zone valves. This valve ensures that the head pressure of the pump is proportional to the number of two way valves being closed. It will by-pass the differential pressure created by the pump as the zone valves close, thus eliminating water hammer noise. The 519 Series is available with conventional NPT and sweat union connections. Also available for size 3/4 in, the Presscon copper tailpiece with union nut makes installation and maintenance fast, easy and efficient. Special slots in the EPDM O-ring allows fluid to leak during system testing if unpressed and provide a perfect leak-proof seal when completely pressed.

Caleffi Differential Pressure By Pass Valve With Graduated Scale, 519 Series, 1-1/4 x 1-1/4 in Nominal, FNPT Inlet x MNPT Union Outlet Connection, Up to 45 gpm Flow Rate, 150 psi Working, 2 to 10 psi Adjustable, EPDM O-ring Seal, Brass, 32 to 230 deg F, 7-3/8 in H

• Brass valve plug, EPDM valve plug gasket, asbestos-free NBR union seals, ABS control knob, stainless steel spring
• 30% water, glycol solutions

• Instruction/Installation Manual https://assets.unilogcorp.com/267/ITEM/DOC/Caleffi_519700A_Manual.pdf
• Specification Sheet https://assets.unilogcorp.com/267/ITEM/DOC/Caleffi_519600A_Specification_Sheet.pdf