Views:4 Author:Site Editor Publish Time: 2019-06-10 Origin:Site
After the solar water heating system is put into use, it should be managed and regularly maintained according to the characteristics and working conditions of the system to ensure the continuous normal operation of the solar water heating system. This paper analyzes the maintenance methods of various parts of the solar collector system, focusing on the analysis of the cleaning and descaling methods of the solar system.
Solar collector system, maintenance and maintenance, solar cleaning agent
The maintenance of solar collector systems includes three main aspects: collector maintenance, heat storage system maintenance, and pipeline system maintenance.
The main point of operation and management of solar collectors is to avoid the air drying operation of the collector, especially the vacuum tube type collector, and at the same time, avoid the boring caused by the non-flow of the collector.
For systems that use antifreeze as a heat transfer medium, check the composition of the antifreeze before the winter season to determine whether it affects the antifreeze and replace the antifreeze.
For systems using water as a heat transfer medium, antifreeze measures such as emptying, recirculation, circulation, and heating can be used to prevent freezing.
When the system is out of use or the water temperature in the summer tank is too high, the collector can be covered with a sunscreen or other items to reduce the sun's exposure and prevent the collector from overheating.
For flat-plate collectors, keep the transparent cover clean, often remove the ash, and ensure a high degree of transparency, usually scrubbing once every six months to one year.
For vacuum tube type collectors, it is best to periodically clean or flush the dust on the surface of the collector as the conditions permit, because the dust will adhere to the vacuum tube, which will affect the transmittance of light and the reflectivity of the reflector. Therefore, the outer surface of the vacuum tube can be scrubbed from half a year to one year. When scrubbing, first scrub the vacuum tube with soapy water or washing powder, then rinse the surface of the vacuum tube with clean water.
The water temperature in the heat collecting system is high, and it is easy to form scale, which seriously affects the heat absorption efficiency of the collector, and needs regular descaling, usually once every six months to one year.
The heat storage system mainly refers to the water tank and accessories, and its maintenance mainly includes:
2.1 Regularly check the tightness of the storage tank and the insulation layer. If the seal is found to be damaged, repair it in time.
2.2 Regularly check that the water supply valve, safety valve, level controller and exhaust unit of the storage tank are working properly to prevent air from entering the system.
2.3 Regularly check for foreign matter entering the storage tank to prevent the circulation pipe from being blocked.
2.4 Regularly remove scale from the storage tank. In some areas, the water quality is hard and it is easy to scale. After long-term use, it will affect the water quality and system operation. It can be cleaned every six months to one year according to the specific conditions.
Due to the high temperature of the solar water heating system piping, routine maintenance of the pipeline is particularly important. The daily maintenance of pipelines mainly has the following aspects:
3.1 Ensure that the pipe insulation layer and the surface moisture-proof layer cannot be damaged or fall off, preventing the occurrence of thermal bridges and dew condensation;
3.2 Ensure that there is no air in the pipeline to prevent hot water from being delivered to each water distribution point due to air blockage;
3.3 Ensure that the system piping is unobstructed, and the entire system is flushed regularly to prevent the deposition of rust and block the pipeline.
Methods for removing scale include physical scraping and chemical cleaning. In general, physical scraping should be preferred where physical scraping can be used. However, the scale attached to the equipment and pipes inside the solar system cannot be removed by physical methods and must be removed by chemical cleaning. The scale deposited inside the solar system equipment is relatively loose, and it is easier to remove by chemical cleaning.
There are many types of solar cleaning agents, such as organic acids, inorganic acids and phosphate cleaners. However, from the perspective of drinking water safety and protection of chromium and nickel in the inner barrel of stainless steel, the acid is relatively moderate. The acid, such as white vinegar (vinegar), citric acid, etc., may be optionally washed with hydrochloric acid added with a corrosion inhibitor (imidazoline).
Solar cleaning agents are divided into two categories, one is solid and the other is liquid. Due to the different state, the cleaning process is also different. The liquid solar cleaning agent does not need to be watered for convenient use, while the solid solar energy needs to be watered. Use, the ratio of water to water is about 5 times the solid component.
The cleaning and descaling steps of the solar system are as follows:
Open the water inlet of the solar water heater;
Add solar cleaning agent to the hot water storage tank;
Automatic thermal cycle for 20 to 30 minutes, so that the cleaning agent solution is in full contact with each part;
Open the drain and drain the cleaning solution;
Refill the water tank for two minutes after filling the water;
Drain the circulating water, and the cleaning and descaling work is completed.
The structure of different solar water heaters is different. Please adjust the usage according to the instructions (it is recommended to be operated by professional maintenance personnel).
Descaling the water to about 40 °C, the effect is better. The higher the water temperature, the faster the cleaning speed, the better the effect, but it cannot exceed 70 °C.
If the scale of the vacuum tube type collector is serious, it is best to disassemble and clean each vacuum tube separately, saving material and cleaning more thoroughly. This requires professional solar installers to operate and avoid bursting when disassembling the vacuum tube.
Inquiry E-Mail: firstname.lastname@example.org
Don’t let a limited budget keep you from getting the comfort equipment you need for your home or business，Sign up to receive our Solar energy expertise by solar pros!