1. One of the two solar water valves is for cold water and the other for hot water. If you don't know which two are, you can simply close them both and then use the corresponding valve. Release hot water. Open the faucet on the hot water side, then try both solar water valves, open them separately and see which hot water faucet starts flowing when opened. This water valve is for hot water. and the other is for cold water.
2. If both water valves are opened separately and no water is flowing from the hot water tap, check if there is a valve of water in front of the hot water tap. If so, open it. Still so, it is possible that there is no water in solar energy. You can open both solar water valves at the same time, water should come out from the tap which releases hot water. Try turning off a water valve. If there is no wateri comes out of the faucet which releases hot water at that time this water valve circulates hot water.
3. After distinguishing the cold water inlet and heat outlet functions of the two solar water valves, after each water use, open the cold water inlet valve to allow solar water to flow out. When full, if water overflows from the solar panel, close the cold water inlet valve (this is not available if automatic water supply equipment is installed, 20 minutes is enough. The hot water valve can be). left open, or it can be opened before each water use and then turned back on. Open the hot water tap.