Link to Drawing
http://www.cyclestopvalves.com/forum/viewtopic.php?t=124 Cycle Stop Valves can control booster systems that pump from a low elevation to a higher elevation. When boosting pressure to a higher elevation, simply pick up the water at a point where the pressure is low and boost it to a higher pressure.
Example #1
A single booster system can be used up to 400 PSI of operating pressure from special designed Cycle Stop Valves. Every floor on the way up the building or mountain can have a pressure-reducing valve set at 40 PSI. This insures that all water usage is at 40 PSI even though the system builds 400 PSI to get 40 PSI to the top floor.
Example #2
An example would be a high rise building with a need for 40 PSI on every floor. Start in the basement with a pump that will boost incoming water to 100 PSI. If 40 PSI is the minimum pressure acceptable at any point in the system then move up to a point 138' in elevation higher than the last booster pump and install another booster system. The second booster system picks up the water at 40 PSI and boost it to 100 PSI again. This process can be repeated over and over again until the uppermost part or floor in the system has 40 PSI. Each floor or level tapped into the pipe system on the way up can be equipped with a pressure-reducing valve set at 40 PSI. This insures that every floor or level has 40 PSI and that none of the pipe system ever sees more than 110 PSI.
When there is a demand for water on any floor, the booster pump below that floor comes on at 100 PSI and the attached Cycle Stop Valve tries to maintain this 100 PSI constant. Each booster pump below the first, sees the booster pump above as a demand, the same as from one of the floors on its' level. Each booster pump below the usage comes on in turn to feed the booster system above.
If there is zero usage the Cycle Stop Valve on that booster pump would allow a small pressure tank to fill at 5 GPM until the pressure rose to 110 PSI and the pressure switch would shut off the pump. When any booster pump shuts off, the booster pump below sees no demand and its Cycle Stop Valve, allows its small pressure tank to fill to 110 PSI and that pump is shut off. All the booster pumps on the way down continue to fill tanks until all are shut off.
In the case of a high rise building the booster pumps would get progressively smaller on the way up as demand decreases. In some cases the building may be large enough that there is never a zero flow condition. One pump in each booster system should be sized to be efficient at very low flow, as it will run continuously. Another pump in each booster station should be sized to handle peak demands. Booster stations with multiple pumps are more efficient and will keep considerable wear off of the larger pumps.
Example #3
Another example would be boosting water over a mountain. A booster station at the bottom of the mountain can boost pressure as high as the pipeline up the mountain can handle. We could boost to 180 PSI and maybe use 200# pipe. Wanting 20 PSI to feed the booster station at the next higher elevation we would go up 160 PSI or 370' in elevation and install another booster. This second booster would pick up water at 20 PSI and boost to 180 PSI again. The next booster would be another 370' above the last booster and the process could be repeated as many times as needed. This will allow all of the booster systems and the entire pipeline to operate at less than 200 PSI, even though it would have taken 1,000 PSI (and pipe that could handle it) to pump to the top of the mountain with a single booster station.
Each booster pump would come on at 180 PSI, the Cycle Stop Valve would be set to maintain 180 PSI, and the pump would be shut off at 190 PSI. When water is demanded at the top of the mountain the small pressure tank on the highest booster station would drain as pressure lowered from 190 PSI to 180 PSI and the pump will be started. The small pressure tank at the second lowest booster station would drain from 190 PSI to 180 PSI and the pump will be started. This process is repeated all the way down the mountain. Each booster stations comes on to feed the booster station above it. The Cycle Stop Valve on the uppermost booster pump will maintain 180 PSI matching the flow being used at the top of the mountain. The Cycle Stop Valves on the other booster pumps will maintain 180 PSI matching the flow required by the next booster station above.
When the flow at the top of the mountain is stopped, the Cycle Stop Valve on the uppermost booster pump allows the small pressure tank to fill at 5 GPM. The pressure slowly rises to 190 PSI and the pressure switch shuts off the pump. The Cycle Stop Valve on the next lower booster pump allows its' pressure tank to slowly fill to 190 PSI and the pump is shut off. This process is repeated all the way down the mountain until all booster pumps have been turned off.
These type systems are fully automatic using simple pressure switches. No wires or telemetry is needed to operate the system. The pumps and the piping are all operating at less than 200 PSI for a 1,000 PSI system. The pipe system can be tapped for use anywhere along the system between the booster pumps. The system horsepower required should be the same with five 20 HP booster systems instead of one 100 HP system. The electrical demand charge will be considerably less starting five 20 HP pumps at slightly different times, verses starting a single 100 HP pump.
There are many variations possible on the above examples. When flow required varies widely, having different size pumps at each booster station will be the most efficient. Low suction pressure cut-off switches are always important when one booster system directly feeds another. Air vents and vac should be used in needed locations. Pressure relief valves should be used in appropriate locations and set slightly above the pressure switch shut off point. All types of electronic monitoring and control systems can be used if needed. However, when using Cycle Stop Valves and pressure relief valves, all pumps can be turned on manually to continue the supply of water even when all the electronic controls have shut down.
