1. Each solar hot water pipe has a heating belt. When the heating belt is heated, solar energy can defrost it.
2. After the solar water heater is frozen, you can wrap the solar pipes with broken quilts or moss to thaw the solar water heater.
3. Use special solar pipes and special insulation for solar pipes. Even at low temperatures of -40°C, it maintains good flexibility. Pipes will not freeze or crack. Special thermal insulation for solar pipelines: the thermal conductivity is between 0.034 and 0.039 W/mk, and it can also play a thermal insulation role at low temperature of -57°C and high temperature of 125°C.
Detailed information:
Thermal conductive materials
In terms of thermal usesolar energy, the distance between the most dispersed collectors and the heat accumulators is relatively long. Hence, heat conduction. The system remains essential. Thermally conductive materials mainly include heat-conductive flow materials and heat-conductive flow pipe materials. Additionally, thermal storage materials can also be used as heat-conducting flow materials in liquid or gas phase states. International research tends to use the same materials in the storage and heat conduction processes to reduce the complexity of the heat exchange system, thereby achieving the goal of reducing system costs. The focus in the future will be on the research and development of new heat transfer fluids such as ionic fluids, as well as new materials for thermal cycle pipes, such asue metallized plastic pipes.
Thermoelectric material
Thermoelectric material (also called thermoelectric material) is a functional material that uses the movement of carriers within a solid to achieve direct conversion of thermal energy and electrical energy. The principle is that solids have different electron or hole excitation characteristics at different temperatures. When there is a temperature difference between the two ends of a thermoelectric material, the difference in the number of excited electrons or holes at the two ends of the material will form a potential. difference (voltage). Thermoelectric materials are mainly divided into four types: semiconductor metal alloy thermoelectric materials, skutterudite thermoelectric materials, metal silicide thermoelectric materials and thermoelectric materials.oxide type ues.
In 2007, Japan led the world in research into oxide-based thermoelectric materials. At present, commercially used thermoelectric materials include PbTe (operating temperature is 230-530°C, mainly used for power generation), Bi2Te3/Sb2Te (operating temperature is 130°C, C at room temperature, mainly used for small-scale energy). production and refrigeration), SiGe (operating temperature The temperature is above 530 ℃, mainly used for space power generation).
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What to do if the water pipe of the solar water heater is frozen
Solar water heaters can also be used during colder winters. As long as they are regulated and protected from freezing, they can be used normally, let alone dodamage caused by frost. However, if management is neglected, freezing can occur.
1. Ordinary water pipes, if not heated with heating tape, but only with insulated cotton pipes, will freeze and crack in the cold winter. Especially aluminum-plastic pipes , if used in winter, will freeze and leak if the temperature suddenly drops.
Solution:
①Drain the water accumulated in the water line during winter dormancy.
② When used in winter, heating tape can be wrapped; The water outlet of the water tank must be equipped with a drain valve. At night or on extremely cold days, drain the water in time. water pipe) after using water.
2. The vacuum tube is frozen. Vacuum tubes in good condition and used will never freeze. However, if incompetent pipes freeze and crack, they will leak.
①Ffollowing the air hose. The tail of the vacuum tube is bruised or the exhaust is not factory clean, but the inner layer is intact and not leaking, so it is not easy to find. This type of pipe loses its thermal insulation effect. Because there is no sun at night, the microcirculation inside the pipe stops and the water temperature at the bottom is low (even if the water temperature in the box is too high to freeze), the temperature drops very quickly when the temperature is extremely low at night, and the middle and lower parts of the leaking pipe will drop to the freezing point, the vacuum tube inflates.
There are two ways to find out. The first is to touch the outer wall of the tube under strong light at midday on a sunny day. If the tube is cold, it is a good tube; hot, it's a bad tube. Replace it. Second, check on a frosty or snowy day that there are nofrost on the leaking insufficiency pipe and there are no or fewer snowflakes falling on it (the heat is dissipated to the outside). This type of pipe is not damaged by freezing, but also experiences significant heat loss, which seriously affects the increase in water temperature. It must be replaced as quickly as possible.
②The water tank contains little or no water. If there is no water in the water tank but there is water in the vacuum tube, the temperature drops suddenly or the temperature drops again after several days of low temperature. Because there is less water in the water tank, the heat capacity is small, the air capacity is large, and the convective heat loss is large. The heat loss to the water in the vacuum tube is near the freezing point and the vacuum tube freezes. because of the ice in the tube!
Solution: Fill the water tank afterafter each use. The box is filled with water and has a high heat capacity. Since there is no air convection, heat loss in the box is relatively reduced and the pipes do not freeze easily.
After two sunny days when the tank is full of water, the water temperature can reach 80 to 99 degrees (outdoor temperature is minus 10 degrees or lower). Even if it is cloudy for four or five days in a row without any heating, the water temperature can still reach over 30 degrees.
Most of them are now equipped with electric heating. When the temperature inside the box is close to the critical low temperature, power is supplied for heating and antifreeze.
3. Due to lack of cleaning, the lower part of the vacuum tube is densely accumulated with scale, which absorbs heat slowly and dissipates it quickly. It is easy tofreeze and freeze when low temperatures are encountered.
Solution: Whenever you suspect scale buildup, clean it in time beforehand.
You also need to pay attention to the method when using solar water heaters. Use them in the right way to ensure the normal operation of the water heater and extend the life of the water heater.
Many homeowners will install solar water heaters on their roof, but when using them in winter, they must take anti-freeze measures. What if the water pipes freeze?
1. What to do if the water pipe of the solar water heater is frozen
1. The temperature drops more quickly in winter. If this caused The water pipe is frozen. In this case, you can find a way to defrost it first. The most direct and effective way is to heat the pipe. First turn off the tap and wrap the tapand frozen water pipes with a cloth to cover the surface. Then, pouring warm water, you can slowly melt the ice, and finally add warm water.
2. Another method is to use an electric heater, wrap it around the pipe and heat it to increase the temperature and slowly melt the ice. Use this method which will consume electricity. , but it is very practical.
2. How to prevent water heater pipes from freezing
1. The best solution is actually to take preventive measures, to prevent water pipes from freezing, and also avoid more problems later, and will not affect water usage. When the temperature is relatively low, all the water in the water heater pipes can be drained and no water can be stored.
2. Wait for the temperature to increase, for example, attWait until the sun rises on the second day, before filling the water heater. Never fill with water when the temperature drops. that night otherwise the temperature drops a lot at night and once it reaches subzero temperatures you will be freezing. And if there is hot water left after taking a shower, you cannot add more because the water heater will freeze.
3. If the temperature is close to freezing, especially at night, some products are equipped with anti-freeze devices. So we can open it in time to achieve the heat preservation effect.
4. Additionally, water pipes and faucets can also be covered and insulated. For example, some insulating cottons can also provide some protective measures to prevent freezing.
My summary: Once the solar water heater water pipe is frozen and later melts, it is prone to frost cracking and vacuum tubee will be damaged, so pay attention to recent days. If the weather changes, take preventive measures in time.