Two types of solar panels are used to heat water for homes or pools. The photovoltaic solar panels or PV solar panels convert the sun's energy into electricity, which then can be used to heat water. Solar panels can also directly heat water by heating water-filled pipes within the solar panels or by heating a transfer fluid such as antifreeze, usually propylene glycol. Pipes within the solar panels will transfer hot water from the panels to a water storage tank or when a transfer liquid is used, the transfer fluid, which is contained in a closed-loop system, is passed through the water storage tank to heat the water. The heat transfer fluid is used in climates with freezing temperatures, while circulating water is used primarily in warmer climates and for pools. Both types of fluid-containing solar panels can develop leaks.
Check if the leak is coming from the relief valve. If the leak is coming from the relief valve, replace the valve. Do not try to repair the relief valve yourself. If other valves are leaking, you may be able to repair them by tightening the nut or replacing the washers.
Locate any water leaks in the pipes of the solar panel. Turn off any pump connected to the solar panel. Disconnect all wires and let the water drain out of the panel. Let the panel dry completely before you start to repair the leaks.
Drill a small hole into the site on the solar panel where you identified a small leak and fill it with epoxy that is made for metal. Let the epoxy dry thoroughly before reconnecting the solar panel.
Use a solar repair kit for larger water leaks. Clean around the leaks with rubbing alcohol or mineral turpentine. Let the area dry. Cut around the leak area with a razor blade before inserting the rubber plug from the repair kit. Use an adhesive such as liquid nails to glue the rubber plug in place.
Call the solar company or a solar provider if you have a pipe leak in a solar panel filled with heat transfer liquid. Do not try to fix the leak yourself.