The method is as follows:
1. Install a ball valve on the solar hot water outlet pipe (inside). When using solar energy, open the valve and open the valve at the same time. of the electric water heater (water inlet and outlet) are closed to allow the use of solar water.
2. When using an electric water heater, close the solar valve and open the electric water heater valve.
3. Solar energy is open pressure-free, while electric water heaters are pressure-tight. If they are used at the same time, the water in the water heater will be pressed against the solar energy, resulting in a water supply situation. In this way, a main valve must be added to each water heater to open whichever one is located. in use and close the one that is not in use.