OM-05815
ULTRA V SERIES
PAGE B - 4
INSTALLATION
Figure 1. Recommended Minimum Suction Line Submergence vs. Velocity
DISCHARGE LINES
Siphoning
Do not terminate the discharge line at a level lower
than that of the liquid being pumped unless a si
phon breaker is used in the line. Otherwise, a si
phoning action causing damage to the pump
could result.
Valves
If the application involves a high discharge
head, the discharge throttling valve should
close gradually before the pump is
stopped.
If a throttling valve is desired in the discharge line,
use a valve as large as the largest pipe to minimize
friction losses. Never install a throttling valve in a
suction line.
With high discharge heads, it is recommended that
a throttling valve and a system check valve be in
stalled in the discharge line to protect the pump
from excessive shock pressure and reverse rota
tion when it is stopped.
Bypass Lines
Self‐priming pumps are not air compressors. Dur
ing the priming cycle, air from the suction line must
be vented to atmosphere on the discharge side. If
the discharge line is open, this air will be vented
through the discharge. However, if a check valve
has been installed in the discharge line, the dis
charge side of the pump must be opened to atmos
pheric pressure through a bypass line installed be
tween the pump discharge and the check valve. A
self‐priming centrifugal pump
will not prime
if
there is sufficient static liquid head to hold the dis
charge check valve closed.
NOTE
The bypass line should be sized so that it does not
affect pump discharge capacity; however, the by
pass line should be at least 1 inch in diameter to
minimize the chance of plugging.
