Solar powered water heaters heat water with the power of the sun. Solar water heater help homeowners save money on their electricity. Solar energy systems require periodic inspections and routine maintenance to keep them operating efficiently. Although they require less maintenance than traditional gas or electric water heaters, they still require repairs. Watch out for scaling, corrosion, and freezing. From time to time components may need repair or replacement. Troubleshooting your solar water heater may allow you to repair the unit yourself, or at least to be more informed on what repairs a service technician will need to make.
A solar water-heating collector is a glass-topped, insulated rectangular metal box containing copper tubing that circulates liquid. In direct systems, the tubing contains water heated by the collector and conveyed directly into the house or a storage tank. In indirect systems the tubing contains heat-absorbing fluid that circulates through a heat exchanger installed in a tank, heating the water in the tank.
Check the solar collectors for dirt, debris, cracks and shading.
Dirt, debris or shade from overhanging vegetation, can prevent the solar collectors from collecting enough energy to sufficiently heat the water. Cracks in the glazing of the solar collectors may let moisture in, which can ruin the collectors. Eliminate encroaching shade. Trim back tree limbs that have grown out and cast shade on the collectors. Keep in mind that the sun’s track over an average day changes shade patterns: a collector fully exposed at 10 a.m. may be shaded at 2 p.m. Check the collectors at different times to verify maximum solar exposure.
Hose down the glass regularly some other objects that might diminish the solar energy.
These objects are mere coatings of dust on the glazing of the collector that also diminishes the solar energy reaching the tubes. Other debris that may accumulate on the glass surface, including bird droppings and leaves, affects system performance, as well. Inspect the glass for cracks and deteriorated seals annually. When required, clean by hand with a sponge or squeegee and mild detergent.
Visually examine pipe insulation and fittings for corrosion or subtle leakage regularly.
In active systems, thermostat-activated electric pumps convey heated water to the storage tank. Pumps should be cycling on and off by 10 a.m. on days with adequate sunlight. If you can’t hear the pump operating, suspect a malfunction in the thermostat or a bad pump. Also look for burst or leaking pipes and valves. Freezing water in an improperly drained solar heating system can rupture pipes and valves.
Observe the pump during the night to determine if the thermo-siphoning check valve is working properly.
If the pump is constantly cycling on and off during the night, this can indicate that the check valve that allows cool water to move into the storage tank may be stuck open. This can cause insufficient hot water levels in the morning. Listen for improper pump operation at night, a sure sign of a defective thermostat. A solar collector incorporates a temperature pressure-relief valve at the plumbing outlet as a safety feature. If the valve is dripping, manually operate its spring-loaded lever to verify proper opening and closing of the valve. If dripping continues after manual operation, replace the valve.
Flush the system and check the pressure gauge if the solar water heater has a drop in water pressure.
Experts recommend checking the water for dirt or other debris because this may indicate a blockage in the pipes.
Check for air trapped in the pipes or pump if the system operates noisily.
Experts say that opening the vent screw on the pump should release any excess air. Air trapped in the plates will need to be flushed by running water back up the supply line.
In an indirect system, the fluid that conveys heat to the exchanger in the storage tank requires periodic flushing.
While this procedure is best performed by a professional, the do-it-yourselfer can at least examine the fluid for signs of contamination or age. If the color of the fluid has shifted to dark brown, flushing and refilling is required. Where the local water contains dissolved minerals, a professional flushing procedure may include use of acidic descaling solutions to dissolve deposits. In climates where temperatures drop below freezing, the heat-transfer fluid contains non-toxic anti-freeze, which must be replaced during the flushing and refilling process.