This is a preheating solar water heater with a design of adding a copper coil to the water tank on the basis of the compact non-pressurized solar water heater.
The water tank itself does not bear any pressure. Instead, the tap water is exchanged instantly through the built-in copper coil in the water tank in exchange for fresh high-pressure hot water. The water tank serves as heat storage here.
To put it simply, people only need to connect the tap water pipe to the water inlet of the copper coil, the tap water will be heated by the heat in the water tank through the copper coil, and the resulting hot water pressure is equal to the pressure of the tap water.
This design can not only get fresh hot water, but also make the hot water under pressure, and more importantly, the cost is more cost-effective, and it is favored by people.
In areas with low latitudes and high temperatures, such as Puerto Rico, Jamaica, Indonesia, etc., people directly use SFD solar water heaters for shower. However, in high-latitude and low-temperature areas, such as South Korea, Denmark, Poland, etc., people often use SFD products as preheating equipment, combined with gas water heaters, to provide medium-temperature hot water for bath, kitchen or heating floor heating.