Low Producing wells many times need a
cistern tank buried in the ground, to store water for normal use
requirements. This makes it possible for a low producing well to work at
its own pace and still allow water availability for the home. The plumbing
of a cistern for use with a submersible pump, makes it possible to have
great water flow, from a limited availability of gallons per minute from
for keeping a cistern
full of water
DEAN BENNETT SUPPLY
A cistern makes it possible to improve peak flow for a home where the water well does not produce enough water to solve your peak demand gallons per minute. This system can be used with a standard 4 inch submersible pump or a constant pressure pump system. We recommend that all pipe be 1-1/4" galvanized steel pipe for long life and durability for plumbing the cistern pump system.
After digging and putting the cistern in the ground, install a 1-1/4" x 21' galvanized steel pipe through a pipe grommet #10105 - 1-1/4" pipe seal grommet inserted into a 2" hole in the tank end. The 21' galvanized steel pipe will give strength to the installation by being held solid with the ground, to keep the pipe from weeping in the tank. The pipe will extend into the cistern tank to the start of the first manhole opening in the tank top.
Install a 1-1/4" pitless adapter onto the steel pipe, at the edge of the manhole opening. The pitless adapter will make it possible to install and remove the pump for servicing, when necessary. Put a short pipe down from the pitless adapter bottom port to a check valve, continuing into another nipple and a 45 degree elbow, then a 1-1/4" x 12" nipple to go into the well cap on the flow sleeve shroud, and install into the pump top. The flow sleeve is important in a large body of water, since the water will go straight into the pump screen if not installed in a flow sleeve. The flow sleeve makes the water rush past the motor whisking away the heat built up by the motor. The flow sleeve needs a minimum of 10 inches of open area between the inlet and the cistern tank wall to prevent starving the pump water supply flow.
Route the pump wires out of the flow sleeve well seal and up along your pipe to the pitless adapter. Continue the wire up through the cistern manhole to the surface where it can go into a splice box to connect to the power wires coming to the cistern. The electrical wires should be routed through a conduit to protect them.
KEEPING THE CISTERN FULL OF WATER
To keep the cistern full of water from the low production well, we suggest using the CISTERN PANEL that has 2 floats that install into the cistern tank. We recommend placing a pipe down from the 2nd manhole opening to attach your floats to so you can control on and off points. Since the well pump is a low production system, you will want to signal the pump on float at a level down from the turn off float, a short distance. That way the pump will run more often, and for short periods of time, but not have as much trouble keeping the cistern full.
We also offer the BW Relay System for this purpose. The BW RH 230V Cistern Fill Water System will have 3 electrodes hang into the cistern to control the water level points. The lower electrode is the liquid ground electrode, which makes certain that a proper ground is there for the system performance. The electrode further up in the cistern, will turn on the well pump to refill the cistern tank. The upper most electrode at the tank top will turn off the power to the well pump when the cistern is full.
Both systems are great for this purpose, and are both fairly simple to install.
You will also want to add an outdoor low water alarm #1005835 to alert you when water level gets too low. The low water alarm will alert you to turn off the power to the submersible pump in the cistern, and investigate why the water is low. One possible reason would be a failed pump in the well, or another reason could be using more water than the well can supply.
You can also protect your submersible water pump with a Franklin Pumptec to shut off the pump if a low water condition occurs and makes the pump start to run out of water.
|Dean Bennett Supply|