300L Compact High-Pressure Thermosiphon Flat Panel Solar Water Heater Made in China by Jdsolar

Flat solar water heaters are designed and developed for small high-rise residential buildings. The water tank is placed on the balcony, roof, wall and other places. Flat solar collectors are placed on balconies, windows, roofs, and walls inside the building bar, making up for the regret that traditional solar water heaters cannot be perfectly integrated with the building and environment due to innate deficiencies. The heat collector and the water tank are separated from each other, and the heat collector can be flexibly installed on the roof, skylight, balcony or wall, and is not limited by location, achieving a perfect combination with the integration of high-rise buildings and the environment.
Classification of JDSOLAR flat solar water heater
According to the different water circulation methods, it can be divided into three types: natural circulation, forced circulation and constant temperature water discharge.
According to the different concentrating methods of the flat plate collector, it can be divided into: condensing type and non-concentrating type.
The market for flat panel solar water heaters is different: the domestic market and the engineering market.
According to the different materials of the flat panel solar heat collector, it can be divided into ceramic solar panels, copper-aluminum composite heat absorption panels, all-copper heat absorption panels, and stainless steel heat absorption panels
According to the structure of the flat panel solar heat collector, it can be divided into tube plate type, wing tube type, snake tube type, flat box type, round tube type and heat tube type.
structure

The flat solar water heater is composed of heat absorbing plate, cover plate, thermal insulation layer, shell and so on.
JDSOLAR Flat Solar Water Heater Heat-absorbing Plate
(1) Function
Also known as heat-absorbing core board, it is a component that absorbs solar radiation energy and transfers heat to water.
(2) Technical requirements
The technical requirements are to have a certain pressure capacity, good compatibility with water, excellent thermal performance, simple processing technology and reasonable cost. Commonly used materials are copper, aluminum alloy, stainless steel, galvanized sheet, places with poor coastal water quality, and plastic or glass steel.
Selective coating: In order to increase the thermal performance of the heat absorption plate, the coating is often sprayed on the metal surface. There are two types of coatings: selective coating and non-selective coating.
The flat plate collector is divided into two types according to the coating type, which are commonly known as black film and blue film (black chrome, anodized)(3) Heat absorber
Also known as the heat absorber, the heat absorber is the core component of the flat solar water heater. It must first complete the light-heat conversion, and then transfer the heat energy to the water to be heated.
The heat absorber is mainly made of metal materials. At the beginning, it was a steel tube plate binding structure. Later, a welded type, an aluminum wing type, and a copper-aluminum composite type appeared. Some have poor thermal conductivity, some have too high energy consumption, some have too many consumables, and some have complicated processes. But in common, heat transfer is tens to hundreds of times higher than glass. For example, the thermal conductivity of copper is about 320, aluminum is about 160, copper is about 40, and glass is only 0.64. The pressure resistance can reach 10KG / CM2, and the glass can't even bear the pressure of 0.5KG / CM2.
Therefore, the metal heat absorber can perform natural circulation, forced circulation and direct current operation. Since the flow rate is proportional to the heat transfer coefficient, the heat transfer efficiency of the metal heat absorber is also much higher.The tube sheet of the heat absorber combined with the new technology, only one punch and two sets of molds can be mass produced, which can be described as less equipment and less investment; only three processes of punching, piercing and pressing can be completed, which is simple and easy to implement; No welding or other auxiliary materials are required, which can be said to save labor and energy. The thin-walled copper tube is used as the exhaust pipe, and the thin aluminum plate is used as the fin. It can be described as scientific compatibility, corrosion resistance, good heat transfer, and material saving.
This structure, when participating in the national flat solar water heater evaluation, has an average daily efficiency of 0.563 and a heat loss coefficient of 1.75, which is the same as the thermal performance of the product that won the first prize at the time.
(4) Classification
According to the different structure of the heat absorption plate, it can be divided into tube plate type, wing tube type, snake tube type, flat box type, round tube type and heat tube type.
1. Tube-plate heat sinkFlat-plate solar collector tube-plate type heat-absorbing plate is to connect the exhaust pipe and the flat plate in a certain combination to form a heat-absorbing strip (as shown on the right), and then weld it to the upper and lower headers to form a flat-plate solar heat absorber board. This is a commonly used structure type of heat-absorbing plate at home and abroad.
2. Wing-tube heat sink
The wing tube type heat absorption plate is made of a heat absorption strip with wings on both sides of the metal tube by a die extrusion drawing process (as shown on the right), and then welded to the upper and lower headers to form a heat absorption plate. Flat-plate solar collectors are generally made of aluminum alloy.
The advantages of flat-plate solar collector wing-tube heat absorption plate: high thermal efficiency, the tube and the plate are integrated, no combination
Thermal resistance; strong pressure resistance, aluminum alloy tube can withstand higher pressure.
Disadvantages of flat-plate solar collector wing-tube heat absorption plate: water quality is not easy to guarantee, aluminum alloy will be corroded; large amount of material, process requires large thickness of tube wall and fins; poor dynamic characteristics, heat absorption plate has Larger heat capacity.
3. Snake tube heat sinkThe snake tube type heat absorption plate is a metal tube bent into a snake shape (as shown on the right), and then welded to the flat plate to form the heat absorption plate. This type of structure is often used abroad. The material of the heat-absorbing plate is generally copper, and the welding process may use high-frequency welding or ultrasonic welding.
The advantages of the flat tube solar collector snake tube type heat absorption plate: no need to weld additional collector tube,
Reduce the possibility of leakage; high thermal efficiency, no combined thermal resistance; clean water quality, copper pipes will not be corroded; ensure quality, mechanization of the entire production process; strong pressure resistance, copper pipes can withstand higher pressures.
Disadvantages of the flat tube solar collector snake tube type heat absorption plate: large flow resistance, fluid channels are not connected in parallel but in series; welding is difficult, and the weld is not a straight line but a curve.
4. Flat box type heat sinkFlat-plate solar collector flat box type heat absorption plate is formed by molding two metal plates separately, and then welded into an integrated heat absorption plate. The material of the heat absorption plate can be stainless steel, aluminum alloy, galvanized steel, etc.
Usually, the spot welding process is used between the fluid channels, and the roll-welding process is used around the flat box solar collector of the flat solar collector.
Flat box solar collector flat box type heat absorption board Advantages: high thermal efficiency, the tube and the plate are integrated, no combined thermal resistance; no need to weld the collector, the fluid channel and the collector are molded by one-time molding.
Flat solar collector flat box type heat absorption plate Disadvantages: the welding process is difficult, and welding penetration or welding problems are prone to occur; the pressure resistance is poor, and the solder joints cannot withstand higher pressure; the dynamic characteristics are poor, and the fluid channel The cross-section is large, and the heat-absorbing plate has a large heat capacity; sometimes the water quality is not easy to guarantee, and both aluminum alloy and galvanized steel will be corroded.
JDSOLAR flat solar water heater cover
(1) FunctionThere is a cover plate on the surface of the heat absorption plate, which requires that it can transmit visible light but not far infrared rays, which makes the energy entered is greater than the lost energy, thereby increasing the temperature rise of the heat absorption plate, which is usually called the cover plate. The effect is the greenhouse effect.
(2) Technical requirements
High total light transmittance, high impact strength, good weather resistance, good thermal insulation performance, good processing performance.
Insulation
(1) Function
The function of the thermal insulation layer is to reduce the heat dissipation of the collector to the surrounding environment, so as to improve the thermal efficiency of the collector.
(2) Technical requirements
The requirements of the thermal insulation layer are good thermal insulation performance, that is, the thermal conductivity of the material is small, and the requirement is not more than 0.055W / (m * ºC), which is not easily deformed or volatilized, and does not produce toxic gases or absorb.
(3) Materials
The material of the insulation layer includes rock wool, mineral wool, polystyrene, polyurethane foamed plastic, etc.
shell
(1) Function
The function of the heat-insulating shell is to form the heat-absorbing plate, cover plate and heat-insulating material as a whole, so it should have a certain rigidity and strength and be easy to install. The material is generally steel plate, aluminum profile, glass steel or plastic.
(2) Technical requirements
In order to ensure the service life of the shell, some shell surfaces need to be sprayed. Generally, the coating needs to be thin and uniform, with strong adhesion and anti-aging properties, resistant to heat and humidity, and not rusty. In addition, the surface should be beautiful, without distortion, dirt and scars.
Design and performance of JDSOLAR flat panel solar water heater
aerodynamic design
Separate installation, streamlined design and shape are more beautiful, making the flat solar water heater a bright landscape on the roof, avoiding visual pollution caused by other solar energy, and achieving architectural integration.Efficient heat absorption
Flat-plate solar collector plate with all-copper core chrome-plated layer or titanium-plated layer, high heat absorption rate, low reflectance, high efficiency heat conduction medium, all copper tube closed medium circulation, coil design, fully improved heat exchange efficiency.
Thermal insulation
The unique pressure-injected polyurethane foam insulation layer (without CFC) of the flat solar water tank has high density, no pollution, long-lasting insulation, and the insulation effect is more durable. The collector uses advanced insulation materials to prevent heat radiation as much as possible.
Corrosion resistance
The outer shell of the flat solar collector is made of marine-grade aluminum alloy sheet, which protects the entire system from the external bad weather such as acid rain and other corrosion. The tank liner adopts the most advanced ceramic powder sintering process in the world today Glaze layer, built-in magnesium anode rod to prevent corrosion.
Fully automatic controlThe temperature difference circulation, fully automatic control, when the rainy day, the auxiliary energy is realized by the controller to supplement the heat energy and maintain the water temperature. 24 hours, 365 days, hot water continuously.
Antifreeze design
The unique medium circulation technology can provide reliable anti-freeze protection for its products even in cold areas prone to frost (-30 ° C).
Pressure design
The pressure-bearing design realizes automatic water filling, and ensures that the water tank is in the state of flood irrigation at all times. The cold and hot water pressure is always balanced to meet the needs of the whole family to use water at the same time, completely solving the trouble of the water temperature rising and falling.
Service life 35 years
The product is durable and efficient. Even under the most severe climatic conditions (Twelve Typhoon, Hail, etc.), it can guarantee a low maintenance rate, so that the system can operate for many years, efficiently and steadily, with a service life of 35 years. 9. No bulging or deflated phenomenon like ordinary solar water heaters b] Common solar water heaters have very low pressure-bearing capacity, and generally only have one exhaust hole, which is blocked by foreign objects or exhaust during installation If the caliber is too small, the pressure cannot be effectively relieved (positive or negative pressure) during water supply or drainage, or the local water pressure is too large, the water flow exceeds the flow capacity of the exhaust port, and the pressure on the bucket will make the water heater rise. Broken or deflated, such as poor heat insulation in winter, the exhaust port is blocked by ice, the material used for the overflow / exhaust port is long-term heated and steamed to soften the exhaust port; the exhaust port and overflow port used during installation The size of pipe fittings, etc.
Performance comparison between JDSOLAR flat panel solar water heater and vacuum tube solar water heater
1. Thermal efficiency
Tablet is higher, more than 95%
Vacuum tube is lower, 80%
2. Life
35 years
20 years or more
3. Pressure performance
It belongs to the connection between metal pipes and can fully meet the requirements of the pressure system.
Under pressure, not under pressure
4. Anti-scaling and anti-freezing performance
The double circulation system is adopted, which is not easy to form scales, can be discharged, and does not freeze at minus 30 degrees.
It is not suitable for the use of a double circulation system, the lower end is sealed, it is easy to scale, and it is difficult to discharge sewage, and the effect is not good in winter.
5. Safety factor
It will not burst the tube, high strength, durable, able to withstand the impact of eggs hail.
Easy to break and easy to explode.
6. Combination of product and construction
Regardless of the overall shape, structural strength and specifications are suitable for combination with the building.
Relatively poor
7. Beauty
Beautiful shape, skylight design, no visual pollution.
Relatively poor, no protective layer.
8. Installation performance
It can be installed on balconies, walls and roofs, which is convenient and simple to install.
Installed on the roof and balcony.
9. Management performance
Split
One-piece, split
10. Water temperature
More than 65 degrees Celsius in summer and more than 50 degrees Celsius in winter.
It is above 60 degrees Celsius in summer and around 45 degrees Celsius in winter.
11. Daily hot water production
Around 80KG / square
no
12. Safety anti-electric wall
All-round anti-electric wall technology solves the hidden danger of electric leakage and ensures the safety of bathing.
13. Liner
Injection pressure, enamel liner, magnesium rod antiseptic, longer life.
A stainless steel liner is used, which is easy to rupture.
14. Electric heating energy-saving design
Energy saving 70% -90% than ordinary electric water heater.
10% energy saving compared to flat panel solar energy15. Insulation water pipe
Built-in special insulation pipe for building, three-layer protection, better insulation and long service life.
16. Fully automatic controller
It can be set to assist heating at any time, for example: when electricity is used, it can be set regularly to use valley electric heating; so is gas.
17. Heat collecting materials
All red copper material, the surface adopts the world's advanced chrome plating or titanium plating coating, recyclable and environmentally friendly.
The glass material has no recycling value and is not environmentally friendly.
18. Environmental protection
Each use of a solar hot water product is equivalent to reducing the emissions of a car for the country and society every year.
19. Energy saving
The heat collecting plate per square meter can replace 150KG of coal burning, which is equivalent to 147 kWh, reducing sulfur dioxide emissions by 4.85KG, nitrogen dioxide emissions by 2.2KG, and soot emissions by 3.75KG.
JDSOLAR flat panel solar water heater product advantages
Thermal performance technology
Solar collectors can be basically divided into three categories according to the heat collection temperature, namely low temperature (below 100 degrees Celsius), medium (_zhong1) temperature (100 ~ 200 degrees Celsius) and high temperature (above 200 degrees Celsius). Flat plate collectors are suitable for low temperature range, vacuum tube collectors are more suitable for medium and high temperature range, low temperature can also be used, but they can not play its advantages.
The main use of solar water heaters in China is for bathing and domestic hot water. The water temperature is generally lower than 60 degrees Celsius. Flat plate collectors have better efficiency and personality. When the water temperature is greater than 60 degrees Celsius, the individuality of the efficiency of the vacuum tube collector is well displayed.
Effective lighting area
Whether it is a flat plate collector or a vacuum tube collector, the solar energy is obtained through the effective lighting area. Therefore, under the condition of the same large collector outer ring area, the larger the effective lighting area, the more solar energy is obtained And vice versa.
Effective hot water
The effective hot water volume of solar water heater refers to how much effective hot water can be obtained by the solar system every day. The hot water is required to be released and used. It is called effective hot water. The hot water that cannot be released is invalid. The effective hot water volume is also very different; the effective hot water volume of the flat panel system is greater than that of the vacuum tube system.
Pressure performance
The flat water heater is a link between metal pipes, which can fully meet the requirements of the pressure-bearing system, but the usual vacuum tube collector hot water system, because the vacuum glass tube is connected to the header or the water tank, it is explained that the silicone rubber sealing ring is used for the link. Cannot meet the requirements of the pressure system. Once the system pressure is high, the vacuum tube and the sealing ring can hardly resist the system pressure due to the friction, which forces the tube to move outward or slide off.
Prevent scaling and freezing
JDSOLAR flat solar water heater and its system use an important performance in the north is how to prevent scaling and freezing. Flat collectors running in the north are susceptible to freezing and freezing, so the JDSOLAR flat solar water heater system uses reflux evacuation technology, or double circulation (also known as indirect system or secondary system) to basically solve the anti-freezing problem of the system. For this reason, the solar collectors exported from JDSOLAR flat-panel solar water heaters to European and American countries, Australia and other regions all adopt a double circulation system. Flat-plate collectors are most suitable for the use of double-circulation systems, while ordinary vacuum tube collectors are not suitable for the use of double-circulation systems due to undesirable pressure bearing.