GENERAL GUIDE TO INSTALLATION & OPERATION
PREFACE: This document is intended as a general guide to understanding the installation and operation of a Nemo Submersible/Flojet Pump Unit. It does not contain complete information regarding safe and proper plumbing and electrical practice as well as information regarding the differing conditions of specific installations. If in doubt, proceed with caution and/or seek professional assistance.
SYSTEMS – Typically, either a storage tank, a pressure tank, or a combination of both (storage tank to booster pump to pressure tank) is part of a submersible pump water system.
OTHER FACTORS include power source voltage and regulation, distance between power source and pump, and height between pump and tank (head). Available power source voltage determines pump voltage. Distance between pump and power will determine gauge of electrical wire relative to pump amperage. For longevity of small submersibles, either a storage tank or combination system is preferred for maximum depth wells but a direct to pressure tank system can work fine for shallower wells.
EXAMPLE: Well depth……………………………………….60′
Distance pump to power…………………….65′
Static water level…………….30′ below grade
Level of pump………………….50′ below grade
Pump amps-volts…………………3.5 @ 24VDC
Wire size…………………………………12 gauge
Height pump to tank………………………….55′
Tank type…………….storage w/float switch
1. Thoroughly read all literature included with the Nemo Pump.
2. Lay out delivery pipe (commonly 100 psi Polyethylene), electrical wires (waterproof stranded copper), and pump near well head.
3. Connect one end of pipe to pump (use s.s. hose clamp).
4. Install appropriate fitting at other end of pipe.
5. Solder electrical wires to pump leads, or connect wires with supplied crimp connectors. To seal connection, use the standard sealant filled submersible pump wire splice shrink tube sealing kit included with each pump. Install exactly as the included instructions indicate; heat from center outward until sealant flows from ends. Do not apply heat directly to wires at ends of shrink tubes; overheated wire insulation will develop cracks and leaks. WARNING: Take Care! If this connection leaks your pump will fail.
6. Bundle pipe and wire at 5′ +/- intervals with cable ties and be sure that spliced wires at pump do not protrude beyond diameter of case.
7. Lower pump into well to a point below static water level (1′ to Maximum 40′ ). A safety line is not required.
8. Connect pipe from tank to pipe from well.
9. Connect electric wires from tank switch to wires from pump. (Protect circuit with 15 or 20 amp fuse.)
10. Review all procedures in thorough detail to determine if entire system and all plumbing and electrical connections have been installed and secured in accordance with professional standards.
CAUTION: Only proceed with plumbing and/or electrical connections if qualified. Otherwise, seek advise of professional plumber/electrician.
WARNING: Major damage to pump motor can result if pump is operated when water in delivery pipe is frozen or otherwise obstructed; Nemo pumps are not equipped with bypass valves.
OPERATION – To prevent pump damage or excessive wear, Pressure Tank Systems must be fitted with a pressure switch that switches pump off before total system pressure exceeds maximum rated pump pressure. Total system pressure is equal to the psi of head (each 2.31′ of head = 1 psi) plus psi of pressure switch shut-off setting. Total system pressure should not exceed maximum rated pump pressure (up to 100 psi for the Flojet pump heads used in the Nemo Submersible Pumps). To prevent overflow and excessive pump wear, a Storage Tank System must be fitted with a float or water level sensor switch. Being that a storage tank is not under pressure, total system pressure is simply equal to psi of head. Pumps operated direct from photovoltaic modules should be protected from low voltage inputs via a manual or automatic (LVD) Low Voltage Disconnect switch at power source. For proper operation of pump, electrical circuit must be suitably fused, grounded, and equipped with main disconnect switch at power source.
APPROPRIATE USE: Nemo Pumps are primarily designed to efficiently supply potable water to off-grid remote site dwellings, garden irrigation, livestock watering, and for other low volume intermittent duty applications. Expected years of maintenance free service will be proportionately shortened if designed use is exceeded by high volume continuous duty applications.
TROUBLE PREVENTION NOTE – Most pump failures are caused by improper installation and/or operation. Extra careful attention should be given to electrical wire connection and waterproofing, submergence depth, total system pressure, motor overload conditions, and excessive or low voltage inputs. (NOTE – The text above is the formal version of the installation procedure, with all the superfluous cautions, warnings, details, etc. In actual practice, the procedure is much simpler than this inflated document suggests. But please do read it; there are a few important points included that could spell failure if ignored.)
FOOTNOTES: 1. The speed (RPM) of the pump motor is proportionate to the voltage level output of the battery or, if the pump is directly connected to a solar module, the voltage level output of the solar module. If the voltage level output is too low, the pump motor can slow, stall, overheat, and possibly burn out. This extreme under-voltage situation is unlikely to happen with a properly balanced battery powered pump system. However, a pump powered directly from a solar module will slow and stall during low light (dusk/night/dawn/cloud) conditions. Installing a Low Voltage Disconnect (LVD) switch between the pump and the solar module will eliminate the dangers of these under-voltage conditions.2. Splice Note: Making a proper wire splice is the most important part of the entire pump installation process and of the few pumps that have been returned over the years, nearly all were found to be flooded due to a demonstratively faulty splice connection. A splice that may seem by all outward appearances to be perfectly good, often is not on closer examination. All it takes is a nearly invisible entry point for water to find its way into a stranded wire and eventually short out a pump motor. The mid section of the splice device can be well executed but if the wires at each end of the splice device are exposed to overheating in the process of heat shrinking the shrink tubes, then the plastic wire covering can become brittle and develop minute cracks….either at the time the splice is made or during the flexing of the wire upon or after installation in a well. In short, it is most important to carefully direct heat ONLY to the shrink tubes, from the middle outward, but NOT to any part of the exposed wires at each end of the tube. Also, if solid copper wire is used to connect the pump to power, then the crimp connected wires need also to be soldered before shrinking on the sealant filled shrink tubes (stranded copper wire works fine with just crimp connectors, but crimp connectors do not make a good connection with solid copper wire unless it is soldered).