The Gasboy Model 52 Pressure Regulator Valve is a specialized control valve designed for use with suction-type island dispensers. Its primary function is to regulate the flow of product through the suction island dispenser, ensuring controlled and safe operation, particularly in fueling systems. This valve is versatile, suitable for installations with Aboveground Storage Tanks (AST) or in booster systems that utilize a submersible pump in an Underground Storage Tank (UST).

The core operational principle of the Model 52 Pressure Regulator Valve is hydraulic. In a closed position, the regulator is held by the head pressure of the liquid in an overhead storage tank. When the dispensing nozzle lever is opened by the operator, it activates the pilot valve. This action unbalances the pressure on the top side of the operating piston poppet assembly, which in turn opens the main valve. This allows product to flow through the system. The main valve opens only as much as needed to supply the amount of product requested by the dispensing nozzle, preventing the air separator from overflowing, even if the suction island dispenser is not actively operating. When the dispensing nozzle is closed, the pilot valve also closes, equalizing the pressure on both sides of the operating piston poppet assembly. This equalization causes the main valve to close, stopping the flow of product through the system. This precise control mechanism ensures efficient and safe fuel dispensing.

For proper installation and operation, the Model 52 Pressure Regulator Valve must adhere to a comprehensive set of codes and regulations, including all building/fire codes, Federal, State, and Local codes, National Electrical Code (NFPA 70), NFPA 30, Automotive and Marine Service Station Code (NFPA 30A), and NFPA 395 codes and regulations. It is crucial that the valve is installed by a qualified installer to prevent malfunctions and ensure safety. A key installation requirement is the removal of the shipping plug from the vent opening for the valve's proper operation. Experimenting with the fuel dispensing equipment without certainty of correct installation is strongly discouraged.

The valve is designed to operate in fueling systems with a maximum pressure of 50 psi. To prevent system failure and product loss due to thermal expansion, installations must include thermal expansion relief valves. These relief valves are critical because thermal expansion can generate pressures exceeding 50 psi, which could damage the valve and lead to environmental contamination. Additionally, a solenoid valve must be positioned adjacent to the shutoff valve at the tank. This solenoid valve serves as a safeguard, preventing product loss in the event of a failure in the downstream piping or the overall system. A specific caution is issued against installing a vacuum anti-siphon valve at the top of a tank when a Model 52 valve is installed at the pump; an electric solenoid valve is the required component in such scenarios.

The shear groove of the Model 52 Pressure Regulator Valve must be located at the same level as the top of the concrete island, with an allowance of +1/2-inch (13-mm). This precise positioning is vital for the system's integrity and safety. Furthermore, the installation must incorporate a shutoff or gate valve to enable the system to be closed off and prevent product loss when equipment downstream from the AST is being serviced or replaced. This allows for safe maintenance without draining the entire system.

Regarding piping, all underground installations should avoid black iron pipe or fittings. Instead, only new galvanized or fiberglass pipe and fittings should be used, installed according to the manufacturer's specifications. Swing joints are essential for underground piping, and shoulder nipples should always be used instead of close nipples. It is also important not to cover any lines until they have been thoroughly air and liquid-tested. Back-filling tanks or supply lines should be done with clean sand, crushed rock, or pea gravel, not cinders or ashes. The fill pipe should not be installed in a tank where it can be submerged with standing water, and the Gasboy fuel dispensing equipment should never be used to remove water ballast from the storage tank. Gaskets should not be used on covers of explosion-proof type boxes, and the sealing compound found within conduit should remain undisturbed. Junction Box covers must be tightened before replacing panels.

Maintenance of the Model 52 Pressure Regulator Valve involves several key components. The suction strainer screen (item 5 in the parts list) requires regular cleaning using a solvent cleaner and a soft brush. When reassembling, the strainer screen must be inserted into the cap first before being replaced into the valve body to prevent crushing. Troubleshooting common issues includes addressing product leaks from the valve vent or pumping unit vent, which could indicate a failed diaphragm (item 11), an obstruction holding open the poppet complete (item 12), or a failed gasket (item 7) or pressure relief valve assembly (item 4). If there is no delivery when the pump is turned on, a failed diaphragm or a blocked valve vent (or an unremoved shipping plug) could be the cause.

The Model 52 Pressure Regulator Valve has undergone a redesign to eliminate the need for a "cold weather" version. This updated standard valve now includes a new diaphragm and a standardized diesel strainer, making it suitable for both warm and cold weather conditions without requiring specialized components for different climates. This enhancement simplifies inventory and ensures consistent performance across various environmental temperatures.

When ordering replacement parts, it is crucial to use the exact part numbers and names as listed in the manual to ensure accuracy and expedite the order. Procedures requiring disassembly of the fueling installation should only be performed by qualified service personnel who are thoroughly familiar with the mechanism. Gasboy maintains a distributor network across the country to service fuel dispensing equipment and management systems, providing expert support.

Safety is paramount when working with the Model 52 Pressure Regulator Valve and associated fueling systems. Installers and service personnel must be aware of the potential hazards, including fire, explosion, electrical shock, and pressure release. It is imperative to follow all safety procedures outlined in the manual, including emergency total electrical shut-off protocols. The EMERGENCY STOP, ALL STOP, and PUMP STOP buttons at the cashier's station do not shut off electrical power to the pump/dispenser; a total electrical shut-off is required in emergencies. All work involving electrical components or electronics requires total electrical shut-off of the unit. Working with flammable fuels and vapors necessitates precautions such as avoiding open flames, sparks, and smoking, and discharging static electricity before approaching the dispenser. In case of fuel spills, emergency cutoff procedures must be activated immediately, and emergency numbers called. Hazardous materials present in electronic enclosures require careful handling, and hands should be cleaned after contact. The manual also highlights the importance of reading, understanding, and following all instructions, and contacting the Gilbarco Technical Assistance Center if any procedure is unclear. Lockout/Tagout procedures must be followed to prevent unexpected energization or start-up of machinery during servicing.

Gasboy 52 - Page 6

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