I am not a pump installer myself. I have gathered the information on this page from an experienced pump installer. Please feel free to use the info on this website as a guide only.
Please check the following points to ensure correct pump operation.
- Pump should not be installed in water over 40 degrees centigrade.
- Direction of rotation of pump must be checked prior to installing in the bore. On three phase pumps, check for direction of rotation before installing pump in the bore. Pump should run anti-clockwise when looking down on pump. Should direction be wrong change any 2 leads at termination box. Motor should be protected with the recommended thermal overloads.
- Correct cable size must be used. (check with electrician).
- Do not use pump to pump sand or gravel. The bore must be developed or rehabilitated and be producing clean water prior to installation.
- If the pump is being used as a pressure system, use the recommended pressure tanks or pressure switch and do not allow pump to short cycle.
- Do not run pump dry.
- Pump is not suitable for use in some types of corrosive water. (If unsure have water tested and seek advice).
- If the pump is throttled back Fig 8. to less than 0.5lps, then an Auto Control Box with water level monitoring probes must be used instead of the standard switch.
- Pump should be installed using suitabe support cable.
- Starting voltage at the pump and frequency must be correct.
- Bore suitability check the following.
- Water quality.
- Is the bore straight.
- Is the bore correctly cased.
- Has the bore got a sand screen.
- Does the bore have sufficient capacity to suit the pump.
- Check the burst pressure of the pipe to make sure that it is compatible with the pump pressure. Refer to section below on Polythylene Pipe Class
INSTALLING PUMP IN BORE
There are many differnt ways to install a Submersible Bore / Well Pump. Here is one method of Pump Installation:
- Splice the bore pump to the submersible cable refer to section below on Cable Splice
- Wire the other end of the submersible cable through the hole in the bore cap and fix. Fig 1. Appropriate electrical fitting may need to be purchased if it is not part of the bore cap. Fig 2.
- Wire the submersible cable to the appropriate Control Device as seen in Fig 1.
- Lay the pump with cable along the ground from the top of the bore, so that the pump is at the bore end.
- Lay the pipe and block the ends of the pipe so that no stones, dirt or gravel can enter the ends of the pipe and lay the pipe along the ground along-side the submersible electrical cable and pump. It is very important that you don’t kink or bend the poly (if using poly pipe) as this can result in the poly splitting later.
- Install the shroud Fig 3. (if needed) refer to section below on Bore Pump Shroud.
- Connect the bore pump to the pipe and bore cap using appropriately rated pipe fittings.
- Make sure there is a non-return valve included on the line.
- Lay the water level monitoring probes (if needed) next to the pipe.
- Tape the probes to the pipe every 3 meters to prevent snarling of cable. Use a strong tape such as duct tape.
- Attach the stainless steel support cable Fig 5. refer to section below on Stainless Steel Support Cable
- You should now see bundled together and laid out on the ground, the pipe and probes taped together. Not taped, but laying along side them is the electrical cable and the safety cable.
- MAKE SURE THE SAFETY SUPPORT CABLE IS CONNECTED TO THE BORE CAP AND SECURED.
- The bundle of pump, pipe, cable, probes and safely cable can now be carefully lowered into the bore taking care not to cut or chafe the cable insulation on the bore casing.
- Lower the pump into the bore slowly without force to approximately 3 metres below maximum water draw down and if possible 3 metres from the bottom of the bore. Make sure the poly doesn't kink at all when lowering it into the bore as it may possibly cause the poly to split later when under pressure.
- DO NOT SET THE PUMP ON THE BOTTOM OF THE BORE.
- MAKE SURE THE PUMP IS POSITIONED ABOVE THE CASING SLOTS.
- Pull on the bore pump support cable so the weight of the pump is on the cable and then fix it.
I will supply more images of a pump being installed down a bore / well soon
PUMP START UP
Partially throttle pump Fig 8. and run until the water is clear of sand or any impurities. Gradually open the throttle valve until the pressure gauge Fig 9. is at the required operating pressure. If the pressure gauge continues to drop once valve is set the water level is dropping in the bore. Close the valve further until a steady operating pressure is shown on the gauge.
If the capacity of the bore is unreliable a flow switch with timer or bore probes (in auto control box) should be used to protect the pump.
BORE PUMP SHROUD
If the pump is being installed below the water inlet level, then a pump shroud should be used. A shroud should also be used in:
- Cascading bores
- Low yielding bores
- Top feeding bores
- If the bore casing is greater than 5”diameter
- If the pump is throttled back more than 25% of it's rated flow
- If the position of the slots in the casing is unknown
- If the pump is being installed in a dam or river
- If the pump is to be set below the production level of the bore
Pump shrouds are installed over the body of the pump and motor. The shroud protects the pump from damage from falling sand and ensures that the water flow past the motor is sufficient to achieve adequate cooling of the motor. Failure to install a shroud can result in motor shutdown and failure.
A pump shroud can easily be made from PVC pipe.
Info on how to make your own shroud
Buy a PVC Shroud Adapter
CABLE SPLICE
After first checking cable size for suitability, proceed with the cable splice. This is a very important step and extreme care should be taken. On three phase pumps, check for direction of rotation before installing pump in the bore. Pump should run anti-clockwise when looking down on pump. Should direction be wrong change any 2 leads at termination box. Proper submersible heat shrinks need to be used to seal underwater joins and all systems need to be properly earthed.
All wiring should conform to national and local codes and be done by a competent electrician.
How to splice submersible electrical cable instructions
STAINLESS STEEL SUPPORT CABLE
Never allow the pump weight to be supported by the electric cable alone. Stainless steel safety cable must always be installed to support the pump. A strong saddle is often used to connect the safely cable to the hole in the brass top on the bore pump. See fig …
The support cable should be secured to the well / bore head fitting which in turn should be able to transfer the weight to the concrete surface pad around the top of the bore casing.
Stainless steel support cable is required to provide insurance for those unfortunate times when the metric poly pipe breaks or loosens in the fittings. It is used for lifting the pump in and out of the bore and to support the pump in the bore so there is no pump weight on the electrical cable or the rising main.
POLYTHYLENE PIPE CLASS
Water delivery pipe, needs to be of sufficient pressure rating and diameter to sustain pressure loads and still deliver adequate flow rates without being restricted by friction loss. All pipe fittings need to be of the same or better pressure rating as the rising main.
Pumps installed down to 120 metres are commonly done so on 40 or 50 mm. Class 12 polythene pipe. Installations to 150 metres should use class 15 polythene up to 2.2 Kw motor size. For depths greater than 150 metres or motor sizes larger than 2.2 Kw use steel or galvanised pipe to install the pump. It is very important to check the pressure rating of the pipe and make sure it is compatible with the
pump pressure.
If you take the pump details along with the depth that you are installing the pump at, to your irrigation store, they will let you know exactly what size pipe to get.
There are many variations to the following method of bore pump installation. I have included these instructions as a general guideline. If you have your own method and have photos which you would like me to include on this site, please contact me
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