During the water storage process of the solar water heater, corresponding equipment should be installed on the water heater to prevent the water heater from overflowing when full.
Most water heaters are equipped with an overflow pipe. One end is connected to the highest water level of the water heater's water storage tank and the other end is connected to the user's house. the water storage is full, the overflow water will flow out by itself to prompt the user to close the faucet in time. You can also install a float valve on the water heater.