CSV1W / CSV1A / CSV2W1.25 General Information
The Cycle Stop Valve model CSV1W, CSV1A, and CSV2W are pump control
valve that automatically adjust pump output to match variable flow requirements.
Downstream of the CSV1W, CSV1A, and CSV2W, pressure remains
constant as long as demand is between the upper and lower limits of the
valve. The 1" CSV1W and CSV1A handle from 1-25 GPM and the 1 1/4"
CSV2W handles from 5-50 gpm.
As flow rates vary, the change in pressure causes the valve inside these
models to modulate closer to or farther away from the valve seat. This
enables the pump to exactly match your demand and the pressure downstream
of the CSV to remain constant depending on pressure fall off. (See
When there is no longer any demand on the system, the pressure begins to
rise and the valve is pressed against the valve seat. The valve and seat are
designed to never be able to completely seal. The non-closing seat is sized
to allow flow of approximately 1 gpm on the 1" valves or 5 gpm on the
1 1/4" valve. As this flow continues past the seat, water begins to fill the
pressure tank downstream of the CSV. As the pressure tank slowly fills,
the system pressure will slowly rise to pressure switch shut off. (Note:
Pressure switch shut off pressure must always be higher than the constant
pressure held by the CSV).
Regardless of tank size, when the tank fills, the pressure downstream of the
CSV rises to pressure switch shut off point and the pump will be shut off.
As flow is again demanded from the system, the pressure tank will empty
and the pressure switch will start the pump.
Model CSV1A and CSV1W are dual threaded and are available in 1" female
NPT and 1 1/4" male NPT. The "1A" model is certified NSF/ANSI 61-G.
It is adjustable from 15-150 PSI (150-300 PSI available), the "1W" model
is preset to 50 PSI and is adjustable from 45-65 PSI. The "2W" model is
available in 1 1/4" female NPT thread and has pressure settings available
from 25-75 PSI or 50-120 PSI. There can be no more than 125 PSI maximum
differential pressure across any of these valves. (Difference in pressure
between inlet pressure and outlet pressure).
Note: In multiple pump applications, never share a CSV
with multiple pumps. Each pump must have its own valve.