5
Outlets Per Pump
Provide at least two
hydraulically balanced main
drains, with covers (see
below), for each swimming
pool pump suction line. The
centers of the main drains
(suction fittings) must be at
least three feet apart.
The system must be built so
that it cannot operate with the
pump drawing water from
only one main drain (that is,
there must be at least two
main drains connected to the
pump whenever it is running).
(See Figure 2). However, if
two main drains run into a
single suction line, the single
suction line may be equipped with a valve which will
shutoff both main drains from the pump (see Figure 2).
More than one pump can be connected to a single
suction line as long as the requirements above are met.
Water Velocity
The maximum water velocity through any suction outlet
must be 1.5 feet (46cm) per second unless the outlet
complies with the latest ASME/SNSI Specification for
Suction Fittings For Use in Swimming Pools, Spas, Hot
Tubs, and Whirlpool Bathtub Applications. In any case,
do not exceed the suction fittings maximum designed
flow rate.
If 100% of the pump’s flow comes from the main drain
system, the maximum water velocity in the pump
suction hydraulic system must be 6 feet (183cm) per
second or less even if one main drain (suction fitting) is
completely blocked. The flow through the remaining
main drain(s) must comply with the latest ASME/ANSI
Specification for Suction Fittings For Use in Swimming
Pools, Spas, Hot Tubs, and Whirlpool Bathtub
Applications.
Hazardous voltage.
Can shock, burn,
or cause death.
Ground pump before
connecting to
power supply.