Trouble Shooting Guide

Here are some common problems with Solar Water Heaters and their solutions. Despite using this trouble-shooting guide, if you are unable to solve the problem, please contact us or any skilled Solar Water Heater installer.

NO water supply from the hot water taps

Check the cold water supply. The valve on the cold water inlet should be open, and the cold water storage tank should be full.

The system is only delivering cold water

This is normal on heavily overcast days. A Solar Water Heater can only heat water when the sun is shining or when there is light cloud. For an immediate supply of hot water, use the electrical backup. If you have used more water that day, the Solar Water Heater will need time to warm up the water again. If neither of the above is relevant, check that there are no obstructions in the collector circuit. The thermosyphon force that circulates the water is rather weak, and it can be stopped by small air bubbles in the collector or by bends in the pipes between the tank and the collector. Check the circulation by feeling the temperatures of the inlet and outlet pipes close to the collector. When the sun is shining, the outlet temperature should be much higher than the inlet temperature. Be cautious, the outlet pipe can be very hot! If you cannot detect the thermosyphon circulation (and there are no bends in the pipes), it is likely that there are air locks in the system. Drain the water out of the collector unit and then refill it. If this does not work, contact us.

There is a large drop in water temperature overnight (more than 100C)

Check the insulation around the storage tank. The warm walls of the storage tank and the pipes close to the tank should not be exposed to the cold night air. Ensure that the insulation is dry. If it is wet due to rain leaking through the cladding, or due to a leak in the tank, then it will not keep the water in the system warm. Ensure that the storage tank is positioned at least 1 foot (30 cm) higher than the collector. The thermosyphon circulation flow may reverse on cold nights if there is too small a difference in height between the storage tank and the collector.

The system delivers only lukewarm water

Ensure that the glass cover on the collector is clean. If it is dirty it will reduce the efficiency of the Solar Water Heater. If necessary clean the glass. Ensure that obstacles are not shading the collector. If possible remove them. Ensure that a non-return valve (NRV) has been installed. If a NRV is not installed, and there are mixing taps (for a shower) in your system, cold water can flow into the storage tank because the pressure in the cold water line is always higher than that in the hot water line. If a non-return valve has not been installed, cold water can mix with hot water, thereby lowering the temperature in the storage tank. The solution is to install a non-return valve or have separate lines and taps for hot and cold water. Contact a skilled installer or plumber. Check the insulation around the water tank, collector and pipes. If the insulation around the tank is draining or wet, a lot of heat can be lost. Repair small holes in the cladding or insulation, or contact a skilled installer.

There is condensation on the inside of the collector glass cover

If this occurs only on cold mornings there is no problem. The air in the collector box always contains some moisture and this can condense onto the glass cover if it is cold. As soon as the sun shines on the cover, the condensation should disappear. If the condensation does not disappear when the sun comes out there is probably a leak in either the glass cover seal or the absorber. You can repair a visible leak in the glass cover seal yourself using a weather-resistant repair kit. For other leakages contact a skilled installer.