Solar Water Pump Troubleshooting: Common Problems and Solutions

A solar water pump is built for reliability with fewer moving parts than a diesel or electric pump, and no fuel or grid power to worry about; it should, and usually does, run without drama for years at a stretch. Still, knowing how to approach solar pump troubleshooting in a systematic way is essential.

When something does go wrong with a solar water pump system, it can bring your water supply to a halt quickly. This is why knowing all you need about solar water pump troubleshooting is crucial, as it means you can diagnose most problems yourself, resolve the straightforward ones without waiting for a technician, and describe the more complex ones accurately when you do need professional help. 

Here are the most common problems and what to do about them. 

Problem 1: The Pump Is Not Running at All

This is the most alarming scenario, but it usually has a simple cause, and therefore likely an easy resolution if you know how to approach solar water pump troubleshooting. 

Start with the solar panels. Check whether they are receiving adequate sunlight. Early mornings, heavy clouds cover, and shadows cast by nearby trees or structures can reduce input power below the threshold needed to start the pump. Clean the panel surface if dirty, and verify that nothing is obstructing the panes. 

Next, check the electrical connections. Inspect the cable running from the panels to the solar pump controller, and from the controller to the pump. More specifically, look for loose terminals, corroded connections, or any visible damage to the wiring. Vibration from wind or general use can loosen connections over time. 

Check the controller display or indicator lights for clues. Most modern solar pump controllers will show a fault code or error light when something is wrong. Consult the manual for what each code means. A low voltage error, for example, usually points back to insufficient panel output or a wiring fault. 

If the system includes a battery backup, test the battery charge with a multimeter. A flat or failing battery will prevent the pump from starting, especially in the early morning before the panels begin generating. 

Problem 2: Low Water Supply 

The pump is running, but the output is noticeably below normal. This is one of the most common solar water pump troubleshooting scenarios, and it has several possible causes. 

Dirty solar panels are the first place to check. Even partial dust or grime on the panel surface can reduce power output significantly. And a pump running on reduced power will deliver lower flow. Clean the panels and observe whether the output improves. 

A blocked inlet filter or intake screen is another frequent culprit. Sediment, algae, or debris can accumulate on the filter and restrict water from entering the pump. Remove and clean the filter according to the manufacturer’s instructions. 

For a solar-powered submersible water pump installed in a borehole, check whether the pump has descended below its optimal depth. If the pump is sitting too close to the borehole floor, it may be drawing in sand and sediment, causing partial blockage and wear. 

Air locks in the pipe system can also reduce flow. This is more common after a pump has been removed from servicing and reinstated. Running the pump briefly with a valve slightly open can help expel trapped air. 

Problem 3: The Pump Runs Intermittently 

If your pump starts and stops repeatedly, the most probable causes are fluctuating power input or thermal shutdown, common among off-grid systems operating without a battery backup. 

Intermittent operation can also result from a dry-run protection feature triggering incorrectly. Most controllers include a dry-run sensor that shuts the pump down when it detects insufficient water at the inlet. If the sensor is positioned too high in the well or borehole, or if the water level has dropped seasonally, the sensor may activate even though water is still present. Check the sensor position and reset the controller after repositioning if needed. 

Overheating is another cause. If the pump motor gets too hot, often because a submersible pump has been partially raised out of the water where it relies on the surrounding water for cooling, it will shut down automatically to protect itself. Here, the solar water troubleshooting and fix is simple: ensure the pump is properly submerged at the correct depth.

Problem 4: Controller Or Inverter Faults

The solar water pump controller, and where present, the solar pump inverter, are both sensitive to heat, moisture, and voltage irregularities. If either unit develops a fault, the pump will underperform or stop entirely. 

Check the controller housing for signs of moisture entering it, condensation, or dust accumulating inside the vents. Ensure the unit is mounted in a shaded, well-ventilated location. A controller exposed to direct afternoon sun can overheat regularly, shortening its lifespan considerably. 

Note that some faults may require a qualified technician to diagnose and resolve, particularly those involving internal component failure or communication errors between the controller and pump motor. 

Problem 5: Noisy Or Vibrating Pump 

Unusual noise, such as grinding and rattling or excessive vibration from the pump, is a warning sign that you should not ignore. 

Grinding sounds in a submersible pump typically indicate sand or grit passing through the impeller, causing abrasive wear. If your water source has high sediment content, you may need to have the pump raised slightly or a pre-filter installed on the intake. 

Rattling or vibration can result from loose pipe fittings or a pump that is not securely mounted at its installation depth. Check that all fixings and brackets are tight, and that the rising main pipe is not vibrating against the borehole casing. 

Original Reliable Solar Water Pumps in Nairobi, Kenya at Irrihub Ke, +254 112 148 880

If you are looking to buy a reliable solar water pump in Kenya, Irrihub has some nice offers you may consider. We sell solar pumps as independent units or as complete solutions (kits). The complete solutions include: 

• Submersible brushless pump
• 600W solar panels 
• Delivery pipe 25MM
• 70M head
• Flow rate of 2300 L/hr.
• Solar panels 
• Pipes and cables 
• MPPT controller 
• Full installation  

When To Call a Professional 

A basic solar water pump troubleshooting routine can help diagnose most of the problems above. However, some faults, such as internal motor failure, pump seal damage, major controller replacement, or any issue involving rewiring, require a qualified technician. Attempting complex repairs without proper training can be an easy way to make the fault worse and void the pump warranty. 

Nonetheless, systematic solar water pump troubleshooting will resolve most issues quickly and keep your system delivering reliable water with minimal disruption. 

If you experience problems with your solar pump, don’t hesitate to contact the technical team at IrriHub to diagnose, service, and repair your system. 

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