Exterior Inspection:

Look for broken, scratched or discolored vacuum tubes on the water heater.

Check the tank shell for any obvious dents, deformations or rust.

Ensure that connections (such as pipe connections, valves, etc.) are well sealed and show no signs of leakage.

Water temperature test:

On a sunny day, after a period of heating, drain the hot water and measure the water temperature with a thermometer. If the water temperature can reach a higher temperature (usually more than 50 degrees Celsius), the water heater heating effect is better.

Collector efficiency observation:

Observe how fast the water temperature rises under the same sunlight conditions. A faster rise usually indicates a high collector efficiency.

Tank sealing test:

Close the upper water valve, wait for a period of time to observe whether the water level drops. If there is no significant change in the water level, the water tank sealing is good.

Bracket solidity check:

Gently shake the bracket to check whether it is solid and not loose.

Accessories check:

Check whether the controller, sensor and other accessories work properly and whether the displayed data is accurate.

Brand and certification:

Find out the brand reputation of the product and whether it has passed relevant quality certifications, such as ISO certification.