MODULATING FLOAT VALVE with
PRESSURE SUSTAINING FEATURE
01/05
F110-13 (Globe)
Classic Series
Specifications
The Modulating Float Control Valve with Pressure Sustaining Feature shall be a pilot operated diaphragm
valve designed to maintain a constant liquid level in a tank or reservoir. It shall throttle open on a lowering
liquid level and throttle closed upon a rising liquid level. The valve shall also throttle to sustain a minimum
upstream pressure during tank filling operations.
The main valve shall be a hydraulically operated, single diaphragm actuated, globe or angle pattern valve.
Y-pattern valves shall not be permitted. The valve shall contain a disc and diaphragm assembly that forms
a sealed chamber below the valve cover, separating operating pressure from line pressure. The diaphragm
shall be constructed of nylon reinforced Buna-N, and shall not seal directly against the valve seat and shall
be fully supported by the valve body and cover. Rolling diaphragm construction will not be allowed and there
shall be no pistons operating the main valve or any pilot controls.
The main valve body and cover shall be Ductile Iron ASTM A536, and all internal cast components shall be
Ductile Iron or CF8M (316) Stainless Steel. All Ductile Iron components, including the body and cover, shall
be lined and coated with an NSF 61 Certified Epoxy Coating applied by the electrostatic heat fusion process.
All main valve throttling components (valve seat and disc guide) shall be Stainless Steel. The valve body
and cover must be machined with a 360-degree locating lip to assure proper alignment.
F1110-13 (Angle)
The disc and diaphragm assembly shall contain a Buna-N synthetic rubber “Quad Seal” that is securely
retained on 3-1/2 sides by a disc retainer and disc guide. Diaphragm assemblies utilizing bolts or cap
screws for component retention will not be permitted.
The exposed portion of the Quad Seal shall contact the valve seat and seal drip-tight. The disc and diaphragm
assembly must be guided by two separate bearings, one installed in the valve cover and one concentrically
located within the valve seat, to avoid deflection and assure positive disc-to-seat contact. Center guided
valves will not be permitted. All necessary repairs shall be made from the top of the valve while the body
remains in line.
Pilot control systems for valves 3” and smaller shall contain a Flow Clean Strainer, Adjustable Closing
Speed Control, Pressure Sustaining Pilot and Modulating Float Pilot. Pilot control systems for valves 4”
and larger shall contain an external Y-Strainer, Adjustable Closing Speed Control, Pressure Sustaining Pilot,
Modulating Float Pilot and Isolation Ball Valves on all body connections. All pilot control systems shall utilize
copper tubing and brass fittings regardless of valve size. The adjustment range of the pressure sustaining
pilot shall be 20-200 psi.
The valve shall be Watts ACV Model F110-13 (Globe) or F1110-13 (Angle) pattern Modulating Float Control
Valve.
8550 Hansen Road • Houston, Texas 77075 • (Ph) 713.943.0688 • (Fx) 713.944.9445 • www.wattsacv.com