GILBARCO VEEDER-ROOT Encore 300 Series, Руководство по установке

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Reference Information
Page 78 MDE-3985L Encore® Installation Manual · May 2006
Check Valves
(Used on Pumps Only)
See PEI publication RP100 and manufacturer’s installation instructions for information on
installing check valve. Install check valve as close as practical to the suction unit. It should be
gravity activated with minimal, or no spring load. Check valves for use internal to the
pumping unit are available from Gilbarco as an order entry item.
Be sure there is only one check valve in each dedicated line. Use of multiple check valves can
restrict flow and cause cavitation resulting in significant flow rate reductions. If multiple units
are to used on a single line, check valves are required at each pumping unit.
Shear Valves
(Generally Used on Dispensers Only)
Note: Shear valves are not required on pumps but installation is discretionary.
See PEI Publication RP100 Recommended Practices For Installation Of Underground Liquid
Storage Systems (Chapter 9) and PEI Publication RP200 Recommended Practices For
Installation Of Aboveground Storage Systems For Motor Vehicle Fueling. A shear valve (
Figure
4-6 ) is an NFPA 30A required safety device. It closes automatically to stop product flow
during a fire or if the dispenser gets knocked off the island. It also provides a means of
manually closing inlet pipes.
For Ultra Hi installations:
• Selection of proper components mounted to the bottom of the strainer housing is critical in
maintaining the proper location of the shear valve groove of the shear valve to the base
plane of the dispenser. You must follow the shear valve manufacturer's required
positioning for this groove.
• A check valve is strongly recommended. When installed, Gilbarco recommends using
N23274, which is approximately 2.5" long and can take the place of the close nipple
located above the union.
• A union is required above the shear valve.
• A Morrison male end shear valve N23047 (Morrison # 636M-0200AV) can be used to
properly maintain the position of the shear groove. The installer should verify that other
manufacturer's shear valves would ensure proper positioning of the shear groove per their
specifications.
• Double poppet shear valves will not fit the Ultra Hi
• Other combinations of unions, check valves, and shear valves may be possible and still
maintain proper location of the shear groove
• Removal of a strainer from the system will void warranty.