Solar water heaters can be used on cloudy days, because solar water heaters can store hot water when the sun is bright, but they cannot be used on long-term rainy days. Then you need to switch to electric heating.

In addition, as long as there is enough light, the solar water heater can be used on rainy or cloudy days.

All solar water heaters have an insulation layer, so the current temperature depends not only on the weather conditions of the day, but also on whether there was enough light in the previous few days. Generally, when the weather is good, the temperature rises by 30-40 degrees during the day and drops by 5-10 degrees at night.

Most solar water heaters have electric heating auxiliary functions. For example, when the automatic temperature control mode is turned on, when the water temperature is not high enough on cold days, it will automatically turn on the electric heater to make the water temperature in the water reservoir reach the set temperature.