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The Basic Operation of a Cycle Stop

If you’re using a pump, or your machinery is, then you should know about cycle stop valves also known as constant pressure valves. These practical and non-electronic parts can replace a wide variety of other valves and perform better too. It will mechanically control the output flow from the pump, matching the usage automatically. Learn all about cycle stop valves, when you should use one, and how you can choose the right one below.

The Function of Cycle Stop Valves

Cycle stop valves are a replacement for variable flow drive systems. The valve will mechanically sense pressure downstream of it and a spring or pilot valve will open or close to increase or decrease pressure. The valve can be set to a certain pressure and will automatically maintain it.

What happens in the typical operation of the valve is that a tap in the system is opened, the compressed air in the pressure tank forces out water to supply the system. This reduces the pressure in the tank, and continues until all of the pressure is used, so the pump isn’t starting for small, intermittent uses of water. It’s not until the system reaches its low point of pressure, let’s say 40 PSI, that the pressure switch turns on the pump. The cycle stop valve will raise the pressure back up to the center point.

The pump will continue to run, producing constant pressure, as long as the system is using some small amount of water, from 5 gpm to as low as 1 gpm. Although, your system may end up running more. This small amount will fill the rest of the pressure tank and cooling the pump or the motor. Once the high end of the pressure range is achieved, such as 60 PSI, then the pressure switch will shut off the tank. The system will start back up again when demand is made on the water.

In this way, these valves provide superior pressure control and variable flow. They can provide minimum flow to cool the pump or motor and they can provide minimum flow to replenish your pressure tank. You can use them to replace large pressure tanks and water towers. As a benefit, they will eliminate water hammers, line breaks as well as transient pressure waves. The valves have a mechanical soft start and soft stop for this purpose. As it is mechanical, it stops fast enough to wave cancel.

You’ll find that cycle stop valves are also superior to constant pressure valves because they do not have small drilled holes for bypasses. On constant pressure valves, these small holes often get clogged through mineralization, just as a showerhead gets clogged. You need to drill larger holes in order to delay this problem, and frequently clean out the hole, or you can simply switch to a cycle stop valve and not worry about it.

What Does a Cycle Stop Valve Replace?

Depending on your specific set-up, you can use a cycle stop to replace these components:

  • Constant pressure pumps (variable frequency drives)
  • Large pressure tanks
  • Water towers
  • Shuttle valves and flow switches
  • Standard pump control valves

Cycle stop valves are installed before the pressure tank and switch. You should set it, in most systems, to the middle of the pressure switch setting. The size of the tank will also factor into the pressure settings of the switch.

The switch is not mechanical and will not use any power when the motor is running or when it’s not. You will find that the power consumption of your pump or motor will decrease as the cycle stop valve decreases flow.

How Do I Select a Cycle Stop Valve?

In order to choose a cycle stop valve for your system, you need to know three things:

  • The system pressure you require.
  • The system flow you require.
  • The maximum output pressure of your pump.

There are many different cycle stop valve manufacturers you can choose from. Your valve professional can help you choose the right cycle stop valve for your system and a manufacturer that makes a quality product you can trust to make your system more reliable and more efficient.

Do you need more information about cycle stop valves? Or are you looking for other solutions to better your system? Whether you’re a large municipality, a private filtration company, or anyone else that needs quality valves, you can reach out to Blue Heron Water Treatment and Well Service, LLC today.

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