Gasboy Atlas Fuel Systems Site Prep Manual - Manual (Page 35)

MDE-4333E Atlas Fuel Systems Site Preparation Manual · November 2011 Page 31
Plumbing Requirements Site Preparation
Dispensers (Standard Flow)
Use new 2-inch, 2-1/2-inch, or 3-inch pipe. If the distance from the STP to the farthest
dispenser is 200-feet or less, use 2-inch pipe. If the distance exceeds 200-feet, use 2-1/2-inch
or 3-inch pipe to the first dispenser, and 2-inch pipe the rest of the way. Trunk lines supplying
multiple dispensers must be larger and must be sized to provide low pressure drop for
anticipated flow rate.
Dispensers (High Flow, Super-Hi, Ultra-Hi)
Use new 3-inch, 3-1/2-inch, or 4-inch pipe. If the distance from the STP to the farthest
dispenser is 200-feet or less, use 3-inch pipe. If distance exceeds 200-feet, use 3-1/2-inch or
4-inch pipe to the first dispenser, and 3-inch pipe the rest of the way. Trunk lines supplying
multiple dispensers must be larger and must be sized to provide low pressure drop for
anticipated flow rate.
Sharing Product Inlet Pipes (Pumps)
To avoid problems with low flow rate, noise, and so on, always size any common pipe to
multiple pumping units so that the maximum flow velocity within the shared pipe never
exceeds the fluid velocity in any of the branches with all pumping units running a maximum
flow output. Check valves (without springs) are required at each pumping unit inlet to avoid
one pumping unit from draining the other during fueling which will result in loss of prime,
flow hesitation, and so on.
Check Valves
(Used on Pumps Only)
For information on installing check valve, refer to PEI publication RP100 and manufacturer’s
installation instructions. Install check valve as close as practical to the suction unit. It must be
gravity activated with minimal or no spring load. Check valves for use internal to the pumping
unit are available from Gasboy as an order entry item.
Ensure that there is only one check valve in each dedicated line (preferred method). Use of
multiple check valves can restrict flow and cause cavitation resulting in significant flow rate
reductions. If installation requires placing more than one unit on a single dedicated product
line, then check valves must be placed at each pump. Check valves must be accessible for
service.
Shear Valves
Dispensers that are knocked off of the island expose fuel. Explosion and fire could result in
severe injury or death. Installation of shear valve is required by NFPA30A. Install shear
valve properly per manufacturer’s instructions.
WARNING
(Generally Used on Dispensers Only)
Note: Shear valves are not required on pumps. However, installation of shear valve is
discretionary and sometimes required. Consult local codes.
Refer to 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.