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CSV125 General Information

The CYCLE STOP VALVE model CSV125 is a pump control valve that automatically adjusts your pump to match your variable demands.

As your demands vary, the CSV reacts to the changes in pressure and opens and closes accordingly. This enables it to hold a constant pressure as long as your demand is more than the minimum control flow of 1 or 3 gpm depending on the model you choose. (CSV125-1 or CSV125-3). We recommend a 1 gpm bypass for 2HP and smaller and a 3 gpm bypass for 3HP and 5HP. If you demand more than your pump can provide at the pressure the valve is trying to hold, the valve will stop actuating at all and open fully. Your system pressure will become whatever pressure the pump can build at that point.

When there is no longer any demand on the system, water will begin to go into the pressure tank and the system pressure will begin to rise. The pressure tank will then refill slowly at the valve minimum control rate of 1 gpm or 3 gpm (not your full pump rate) until it reaches shut off pressure. Keep this in mind when choosing your pressure tank as this function allows for a much smaller pressure tank to protect your pumping system than you would be able to use on a standard system without the CSV valve controlling the pump. Motor manufacturers recommend a minimum 1 minute of run time any time your pump is called to come on. The time it takes to refill your pressure tank will guarantee that run time regardless of how you use water.

When water is again demanded, the pressure tank will empty causing the system pressure to reach cut in pressure and the pressure switch will start the pump.

Note: Pressure switch shut off pressure must always be set higher than the pressure regulated by the CSV. Maximum pump shut off pressure or total head cannot be more than 150 PSI. It is very important that this model not be installed in a bind or pulled apart at the center as it can bend or separate over time and begin to squirt water.

The CSV125 is a vented valve (it vents air when it actuates). Over time, (how long usually depends on water quality) the air chamber can fill with water and the CSV125 can begin to vent that water to atmosphere. (That drip is a function of the valve actuating and not a leak) The CSV125 valve will function correctly whether it is venting air or water. The CSV125 can also be installed in the well casing and can support weights of up to 500 lbs of pump/pipe. In models sold prior to August of 2016, if your water is high in iron or sulfur, an additional vent is needed. Please call for instructions on how to add an extra vent if needed. On models sold after July of 2016, a modification was made that allows for high iron or sulfur water without any further venting necessary. If venting of water "weeping" is not acceptable for your application, an alternative model for most of the same applications would be the CSV1A or CSV2W.

Note: In multiple pump applications, each pump must have its own valve.

Cycle Stop Valves® is a registered trademark.
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Cycle Stop Valves, Inc.
10221 CR 6900
Lubbock, Texas 79407
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Fax: 806-885-1994