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Principle of Solar water heater heating collectorThe vacuum tube is the core of solar water heater,its structure is similar to an elongated thermos bottle which has vacuum space between inner and oute

Principle of Solar water heater heating collector


The vacuum tube is the core of solar water heater,its structure is similar to an elongated thermos bottle which has vacuum space between inner and outer glass.On the surface of inner glass is coated with spectral selective absorbing painting using a special process for maximum absorption of the solar radiant energy .When the sunshine on the heater,the photons hit the coatings making the solar energy transform into the heat energy.The water absorbs heat from the outer coating to make the water temperature increase and the water density decrease.Hot water moves upward while the proportion of cold water drops.Hot water is always at the top.



Principle of vacuum heating tube


Zijin efficient instant heating tube

     A variety of rare material and coating technology (copper target ,stainless steel target , aluminum target ,argon , nitrogen ) are adopted ,Zijin two-way absorbing coatings are applied to the inner tube to improve thermal efficiency through two-way heating .Heat-absorbing efficiency becomes better than ordinary vacuum tubes .The aborption rate of unique second-generation coating Cr-AL-N/Cu is averaged 0.95 plus.

    Technology upgrading: the performance is further upgraded by adopting materials of high deposition rate and advanced design techniques.Consequently , the overall performance is significantly enhanced:more high temperature(up to 300℃) , more efficient (heat absorption ratio of 0.95),lower heat loss (as low as 0.04).

    Optimized coating design:to absorb multi-band solar radiation by optimizing coating structure to improve integrated absorption of collector tube ; to change the physical structure of the traditional infrared reflective layer by careful design so as to effectively reduce the vacuum radiation heat loss.As a result, the coating adhesion becomes stronger and the density becomes even higher,which improves the anti attenuation effectively of vacuum light.

图片8.jpgPlease refer to structure of  vacuum heating tube as shown.

The sun shines through the glass on the heat-absorbing unit.The solar selective absorbing film turns the solar radiation into heat energy.The endothermic heat will quickly vaporize the small amount of mediums and quickly drive them to the end of condensation,which will become condensed fluid after the release of latent heat of vaporization .Then the condensed fluid will flow back into the evaporating part of the heating tube under gravity.In this way ,more and more water is produced under the circulation of vapor-liquid phase change due to less mediums in the heat tube.The vacuum heating tube should be placed at an angle more than 10°with the ground to ensure the condensed fluid can flow back into the evaporating part of the heating tube.

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Principle of Solar collector




1.Max. pressure bearing: 8 bar/116 psi.

2.Possible to be connected with existing energy source.

3.Water tank may not be installed together with the collector.

4.The pipeline is made of copper and conducted  by  heat  transfer medium liquid .The  vacuum  tube does not  take water . The coating is a     high strength stainless steel with air flow design, which is furnished in good style.

5.It's possible to withstand high pressure in working condition.

6.Module design ,free combination to meet the demand of large water consumption.

The heat pipe series of solar collectors are always connected with existing heating supply device . The selective coating on the inner glass of the evacuated tubes converts solar energy into heat energy and transfers heat to the heat pipes by aluminium fins. The liquid in the heat pipe changes into vapour and rises to the condensation end . The heat passes through the heat exchanger into the inner wall of the vacuum tube and then transfers through the copper pipes into the liquid. The transference of heat into the liquid creates a continuous circulation as long as the collector is heated by the sun.

Introduction to pressurized tank


With high pressure resistant design , the water tank adopts SUS304-2B or SUS316L stainless steel and special welding technology ,its thickness is 1.2mm-2.0mm,and directly connected to pressurized water supply is permitted.

Press resistance capability is 6 bar , if the pressure exceeds,the exclusively-used P/T valve will be released.

The outer tank material is imported from Korea which is high quality and its thickness  is 0.5mm.

The super long and big magnesium stick can protect the tank free of scale.

The long enough exchange stainless steel pipe (16m) assures very high exchanging efficiency in solar system .The outlet of copper adopts special copper, good in sealing performance and easy to install.

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Working principles of Split pressurized system

1522309579873640.jpgThe split pressurized solar water heater is a kind of split pressurized hot-water system of indirect heat exchange and forced bi-circulation. It can be installed on the roofs, walls, balconies and other locations, so as to achieve the perfect combination of solar heat collectors and buildings. The storage tank can be fixed in many places and the insulating tank is equipped with the standard heating device and automatic thermostat.In addition,it is also provided with the enlarged anode magnesium rod.The vacuum tube doesn’t foul and explode,but it can resist pressure, supply hot water in all weathers and automatically run, which represents the development orientation of solar water heater and of which application becomes wider and wider.

When the temperature reaches the set volume,the pump automatically starts to work in circulation.

The circulation pump makes heat-conducting liquid circulate automatically.

The heat-conducting liquid transfers heat to water by the heat exchanger.

The circulation pump will automatically stop working whenever water temperature is below the set volume.

The electrical heater is standby in case the temperature of the water tank is low.


Collector and storage tank may  be  placed in separate places . The tank can be placed in any places indoor. And the collector can be put on the inclined roof or flat place !

Module design, free combination, perfectly matches with the building plus automatic digital operation control.

                         Mini Diagram of Installation

Compact pressurized solar water heater




This is a new type of pressurized  water heater using  advanced heat pipe and all glass vacuum tube technology. The efficient collector tube heat  from sunlight and delivers heat to the condenser. Condenser does not contact water directly. It  is through the copper cap to release the vacuum tube and then to make water hot. The available size of the tank ranges from 100L to 300L. It has the following features.

1) High pressured water tank (Max testing pressure12 bar),using SUS304-2B,1.2mm

2) No outlet is arranged and less heat loss as compared to the non pressured model.

3) Highly efficient heat pipe technology.

4) Vacuum tube does not take water.

5) No sealing rubber is needed and hence no leaking worries.

6) Easy plug-in installation.

7) Freezing resistance.


Schematic diagram of Compact pressurized solar heater




1.It is applicable in cold climate as it has perfect anti-freezing    function.

2.Being pressurized , the unit can be freely installed.

3.It can be installed with the existing heating system such as gas heater ,oil heater.

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Flat type solar water heater

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Flat plate solar collector can be applied to split pressure type,compact pressure,non pressure type and also solar project, arbitrary combination.

Technical Specifications:

1. High quality Copper and Aluminum plate,heater pipe diameter up to 22mm,no welding seam, high intension,and strong pressure resistance.

2. Coating: black chrome or selective absorption coating , long life,high temperature.

3. Tempered glass:high thermal conductivity,high insulation ,long life, the thickness of 4mm or 5mm.

4. Aluminum frame : beautiful appearance and corrosion resistance.

5. Special insulation layer:low heat consumption,high efficiency  and nice looks.

Preheat compact pressurized solar water heater




Working Principle

     One copper coil is installed inside the tank as the heat exchanger. When water flows  into the copper coil, it absorbs the heat of the water in the tank via the copper coil therefore the water tank serves as heat storage tank.


1) All time available if need for hot water:The advanced design integrated with high efficiency preheating patented technique makes water warm up quickly when flowing   through special pipes. It overcomes the shortcomings of traditional SWH,such as slow heating,long waiting time.

2) Enlarged Capacity:We use a special heat exchanging model to avoid mixing water,so water can be heated at any time.

3) Strong water pressure:The water pressure from the heater is as strong as tap water and is very suitable for tired person.

4) Economical and Environmental protecting:clean energy plus green energy.

5) Easy operation: Automatic replenishment and easy operation.

6) Fashionable looks:Fashionable looks and workable with existing equipment.

7) No corrosion or scaling.