1. Vacuum tube
Vacuum tube is the core component of solar water heater and the "heart" of solar water heater. Its quality directly determines the performance of the entire water heater. The performance of the vacuum tube is affected by the coating technology and processes such as cleaning, coating, vacuuming, and sealing. However, the vacuum tubes used in some ultra-low-priced solar water heaters have the following defects: the vacuum degree is low, only 1/100 of that of high-quality products; a large amount of impurities and water vapor remain in the tube, which become gas when encountering high temperatures, and the vacuum degree is reduced; low vacuum state The stability of the lower film layer is poor, and the film layer will age and fall off within two to three years, resulting in a sharp decline in heat collection performance and unable to absorb enough heat. This is fatal. Therefore, it is very important to choose a good quality vacuum tube, which directly affects the life of the solar water heater.
2. Insulation layer
The hot water produced by solar water heaters during the day is stored in a water storage tank. If the insulation performance of the thermal insulation layer is not good, it cannot be used overnight or on rainy days, or it is not easy to use. The main reason for the poor thermal insulation performance of solar water heaters is the thermal insulation layer of the water heater. The quality of the thermal insulation layer determines the temperature of the hot water and the amount of hot water. A good insulation layer adopts imported raw materials, such as polyurethane, which has low thermal conductivity and high temperature resistance; the insulation process adopts automatic constant temperature and high pressure quantitative foaming, and undergoes high temperature curing treatment, which has high insulation performance and is stable and lasting. However, some inferior materials have high thermal conductivity and uneven foaming. The temperature can drop more than ten degrees overnight, and there will be no hot water in rainy days. Some black-hearted companies even use self-made benzene boards in order to reduce costs. After a few months, the thermal insulation effect has plummeted, and after a year or two, they will not be thermally insulated.
3. Inner tank
At present, most solar water heater manufacturers claim that the inner tank of the water tank is stainless steel. The same is stainless steel, but the chromium and nickel in stainless steel are quite different. Good solar water heaters use high chromium and nickel stainless steel inner tanks to ensure that the inner tank is durable and strong in corrosion resistance; inferior inner tanks are mostly made of low-grade stainless steel, which basically does not contain nickel, has poor corrosion resistance and short service life.
4. Installation and service
Solar water heaters have very high requirements for installation, and professional installation is the basis and guarantee for their good use in winter. Some miscellaneous companies often find people to form an installation team, and they rush to work without formal training. These people do not understand the professional knowledge of pipeline design, the fixing of the main body of the water heater, and the subsequent maintenance of the product, which causes problems. Everywhere, it directly affects the "standard life" of solar water heaters. For example, for the fittings used to fix the water heater mounting bracket, the big brands mostly use steel wire, which is strong and corrosion-resistant, but some small manufacturers use iron wire for fixing. Few solar water heaters crashed to the ground.