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Boosting Pressure in High Rise Buildings or Uphill
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 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. This 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 it's Cycle Stop Valve allows it's 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 there 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 horse power 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.
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