Troubleshooting Circulation Pump Failures in Solar Hot Water Systems

A cold shower?  Strange noises?  Pump running continuously?  All signs that the circulation pump on your solar hot water split system is not functioning!

How does a circulation pump on a solar hot water system work?

The pump is usually controlled by a thermostat or a differential controller that monitors the temperature difference between the solar collector and the storage tank. When the temperature in the collector is significantly higher than the temperature in the tank, the pump is activated to circulate the hot water from the collector to the tank until the temperatures reach a set point.

What are the typical signs of a circulation pump failure?

1. No Hot Water: If the circulation pump is not functioning properly, hot water from the solar collector may not be effectively transferred to the storage tank, resulting in a lack of hot water in your taps or showers.
2. Cold Water at Taps: You may notice that the water coming out of the taps or showers is consistently cold, even when it should be heated by the solar system.
3. Reduced Water Pressure: A malfunctioning circulation pump may lead to reduced water pressure throughout the system, resulting in weaker flow from taps and showers.
4. Unusual Noises: Strange noises, such as grinding, rattling, or clicking sounds, coming from the vicinity of the solar hot water system may indicate an issue with the circulation pump.
5. System Overheating: In some cases, a malfunctioning circulation pump can cause the system to overheat, potentially damaging components or causing leaks.
6. Visible Leaks: Leaks around the circulation pump or other components of the solar hot water system could indicate a problem with the pump or its connections.
7. Lack of Movement in System Indicators: Many solar hot water systems have indicators, such as flow meters or temperature gauges, that show the movement of water through the system. If these indicators show no movement or unusual readings, it could suggest a problem with the circulation pump.
8. Red Flashing Lights on Controller: Many solar hot water split systems have a display with warning lights on the controller box to indicate an error.  Such examples of warning lights include TS sensor error (Tank Storage Sensor error), or TC sensor error (Roof Sensor error) or controller default codes.
9. Circulation Pump Running Continuously:  In a typical solar hot water system, the circulation pump should not run continuously.   This could indicate a malfunction or a misconfiguration in the system.

Can I test the system to see if the system is generating solar function?

Yes, if you suspect an issue with your solar hot water system’s circulation pump or solar function, you can perform a simple test to determine if it’s functioning properly:

1. Turn Off Circuit Breaker: Switch off the circuit breaker that supplies power to your hot water system. This ensures that the system is running solely on solar power and not the electrical backup.
2. Monitor Hot Water: After turning off the circuit breaker, monitor the hot water supply from your taps or shower. If the water remains hot despite the circuit breaker being off, it indicates that the solar is still providing hot water.
3. Observe Temperature Change: If the water begins to cool down after turning off the circuit breaker on a sunny day, it suggests that the solar function of your hot water system is not operating correctly.

If your solar is not functioning, turning your circuit breaker back on will restore hot water in the interim.  It’s important to address the issue promptly to avoid further damage to the system and ensure the efficient operation of your solar hot water system.

Contacting a professional technician experienced in solar hot water repairs is recommended for proper diagnosis and repair. Find out more about how we can help you or get in touch with your questions. Ask for a free quote today Call 0416 075 682 or Contact Us HERE.