Specifications

11
PLUMBING
Use proper quality approved fuel line materials with at least 2” inner diameter on the suction side
from the tank and at least 1-1/2” inner diameter on the return / discharge side back to the tank.
Note: Do not put any stress on plumbing of STS 7030 and use a backing wrench when
connecting the external plumbing. Whenever possible a FLEXIBLE CONNECTION
SHOULD BE USED TO REDUCE STRESS on the plumbing and prevent damage from
thermal expansion.
The pick-up tube/line(s) should originate from the lowest point of the tank (to remove all water),
should be connected directly to the system’s “PUMP INLET – SUPPLY FROM TANK” port located on the left
hand side of the enclosure and kept as short as possible. It is recommended to install an oversized,
low restriction foot valve to keep the system primed, especially if the “PUMP INLET – SUPPLY FROM
TANK” port of the system is located above the lowest possible fuel level in the tank. A priming tee
should be installed on the highest point of the suction line to be able to easily prime the lines and
system.
The return line(s) should be plumbed to the “PUMP OUTLET – RETURN TO TANK” port (on the right side
of the system) and enter the tank as far as possible from the pick up tube close to the tank bottom. A
(swing) check valve may be required on the return line(s) on some installations to prevent back flow
pressure.
Multiple suction and/or return lines may be connected to a manifold outside the STS 7030 (see options
list).
Anti-Siphon or other external plumbing devices may be required – please check local regulations / code.
The system capabilities are 15 ft suction (vertical) or 100 ft horizontal lift, when connected to (suction)
piping of 2” ID or more with no additional flow restrictions such as valves, 90-degree connectors or other
plumbing accessories. For continuous optimal performance, make sure suction and discharge lines are
free and that nothing is blocking the flow of fuel and that the suction line always stays primed.