The water cannot be discharged and will not freeze, because the vacuum tube of the solar water heater has a two-layer structure and there is a vacuum structure between the layers. It has no thermal conductivity. the heat absorbed during the day will be stored in the water and the water can maintain a certain temperature. It does not freeze, so solar water heaters are generally not prone to freezing and cracking in winter.
Detailed information:
The structure of an all-glass vacuum tube consists of an inner glass tube, a selective solar absorption coating, a vacuum interlayer, a protective glass tube, a support (spring clip), a getter, etc.
1. The inner glass tube is used as a water flow pipe;
2. Selective solar absorption coatings such as copper oxideglass, black nickel, black chrome, black zinc and black. copper is The outer surface of the inner glass tube is evenly coated using vacuum deposition, spraying technology, electrochemical treatment and other processes to absorb solar radiation energy
3. glass tube. The glass tube is sealed in the protective glass, and then a vacuum is established between the inner and outer glass tubes to form a vacuum interlayer with a vacuum degree of 0.05 Pa to reduce heat loss due to to convection and air conduction, which is similar to the principle of a thermos bottle
Baidu Encyclopedia- Solar vacuum tube
It is indeed easy to explode the pipe at noon when the temperature is high and the sun hit hard. But when the waterless solar energy is exposed to direct light from thesun, it is easy for the pipe to burst when water is added. At that time, solar energy without water will have a very high temperature under the sun. If cold water is added, it will heat and shrink too quickly. The pipe will explode.
Users are reminded not to air dry the vacuum tube. This would reduce the life of the vacuum tube and cause changes in the heat collection effect and molecular structure of the film layer due to air drying, reducing the life.
Detailed information:
Evacuated tube solar water heaters have an efficiency High thermal and can be used on sunny days in summer, the water temperature can reach boiling point in less than two days. If the water is not used for a long time, for example while traveling or traveling, the water tank will be subject toat a high temperature. pressure for a long time.
This will accelerate the aging of the silicone seal ring and the aging and shrinkage of the polyurethane insulation layer of the water tank. Sometimes the exhaust is not smooth and the pressure is too high, which will cause water. The tank may swell and become damaged. At the same time, it is easy to produce scale and shorten the life of the water tank.