Split Solar Water Heater

I. Product Introduction

The flat-panel split solar water heater (Split Solar Water Heater) is a solar water heating system specifically designed for modern high-rise residences, villas, and small-scale commercial buildings. This product adopts a split structure, with the flat collector installed on the roof or balcony, and the stainless steel double-pipe water tank placed indoors or in the equipment room. They are connected through a circulation pipeline, which not only ensures the overall appearance of the building but also achieves efficient and stable hot water supply. 

The flat plate collector is equipped with a high-strength aluminum alloy frame and low iron tempered glass. The interior features a full copper flow channel, and the surface is covered with a highly selective heat absorption coating (blue titanium film). The absorption rate is ≥ 95%, and the emission rate is ≤ 5%. The thickness of the collector is only 80mm, which can be perfectly integrated with the building roof or balcony railing, achieving the integration of solar energy and architecture. 

The inner liner of the water tank is made of 304/316 food-grade stainless steel. It is equipped with a double-tube heat exchanger: the lower tube is connected to the flat collector for solar heating; the upper tube can be connected to auxiliary heat sources such as boilers, heat pumps or gas wall-mounted heaters to achieve multi-energy complementarity. The double-tube design not only improves the heat exchange efficiency but also provides users with flexible heat source selection, ensuring round-the-clock hot water supply. The water tank can withstand a pressure of 0.6 MPa, and the water output pressure is constant, providing a bathing comfort level comparable to that of an electric water heater. 

II. Technical Parameter Table

Split Solar Water Heating System

Stainless Steel Water Tank

III. Working Principle

The flat-panel split-type solar water heater adopts the principles of forced circulation indirect heat exchange and dual-pipe multi-energy linkage:

1. Solar heat collection: The flat-panel collector absorbs solar radiation and heats the internal anti-freezing medium.

2. Temperature difference circulation: When the temperature of the collector is 5-8℃ higher than the temperature of the lower part of the water tank, the controller activates the circulation pump, pumping the high-temperature medium into the lower pipe, and the heat is transferred through the pipe wall to the domestic water in the water tank, and the cooled medium returns to the collector.

3. Auxiliary heating: When the water temperature in the water tank is lower than the set value (such as 45℃) and solar energy is insufficient, the controller automatically starts the auxiliary heat source (electric heating, heat pump or boiler) connected to the upper pipe to supplement heat for the upper water layer of the water tank, ensuring constant-temperature hot water output.

4. Pressure-bearing water supply: The water tank is directly connected to the tap water, and when the hot water tap is turned on, cold water is pushed into the bottom of the water tank, and hot water flows from the top. The water pressure is constant.

5. Anti-freezing protection: When the temperature is low, the controller automatically starts the circulation or activates the heating belt to prevent the collector and pipeline from freezing.

IV. Product Advantages

1. Stainless steel double coil tubes, complementary functions

The water tank is equipped with a double coil heat exchanger. The lower coil is specifically designed for solar energy, while the upper coil can be connected to various auxiliary heat sources such as electricity, gas, and heat pumps, enabling year-round and all-day water supply. This is particularly suitable for regions with variable climates and commercial settings. 

2. Flat plate collectors, integrated with buildings

The appearance of the flat plate collectors is modern and smooth. They can be directly installed on balcony railings or sloping roofs without damaging the architectural beauty. They are the preferred choice for high-rise residences and villas. They have high efficiency in low-light conditions, and there is no tube explosion or dust accumulation. 

3. Stainless steel inner liner, pressure-resistant and corrosion-resistant

The inner liner is made of 304 food-grade stainless steel, combined with automatic argon arc welding and passivation process. It can withstand a pressure of 1.2 MPa test, has strong corrosion resistance, is economical and durable, and offers high cost-effectiveness. 

4. Split design, flexible installation

The collector and the water tank are separated. The water tank can be placed indoors, in a loft, or in a basement, effectively solving the problem of lacking roof space in high-rise buildings and reducing heat loss in the pipelines. 

5. Intelligent dual-source control, energy-saving and convenient

The intelligent controller can set the priority of solar energy or auxiliary heat source separately, and automatically switch between them. This maximizes the utilization of free solar energy, resulting in an annual energy cost savings of 60% to 80%. 

6. Pressure-resistant operation, constant temperature comfort

The system has a pressure of 0.6 MPa. The water pressure is the same as that of tap water, ensuring a stable bathing experience and completely eliminating the problems of thin water flow and large temperature fluctuations in traditional solar water heating systems. 

V. Factory Advantages

Our company has been dedicated to the research and manufacturing of split-type solar water heaters for over a decade, possessing a complete industrial chain and rich export experience.

1. Certifications: We have obtained international certifications such as ISO9001, ISO14001, CE, and Solar Keymark. Our products are exported to Europe, Central and South America, the Middle East, and Southeast Asia. 

2. Core production: We have an automatic welding line for flat plate collectors, a CNC processing and foaming line for stainless steel water tanks, and we produce key components independently. The quality is fully controllable throughout the process. 

3. Dual-coil tube expertise: The dual-coil tube structure independently developed by our company has been optimized through fluid simulation. It features high heat exchange efficiency, and the upper coil tube can be customized with interface specifications and power according to customer requirements. 

4. Customization capability: Supports OEM/ODM customization of parameters such as water tank volume, number of coil pipes, auxiliary heating methods, and collector size, to meet the requirements of various projects. 

5. After-sales Guarantee: The entire machine is covered by a 2-year warranty, the inner liner and coil tubes by a 3-year warranty. Installation videos, technical manuals and remote guidance are provided. 

VI. List of Accessories

VII. Installation Precautions

1. Orientation and inclination of the collector: Facing south or 15° to the west of south, the inclination should be within ±10° of the local latitude. Avoid obstructions.

2. Position of the water tank: The water tank should be placed near an interior load-bearing wall, with a reserved drainage floor drain on the ground. For double-pipe water tanks, an interface for auxiliary heat source piping needs to be reserved.

3. Circulation pipeline: The length of the solar side circulation pipeline should not exceed 20 meters. It should be insulated (≥30mm), and an electric heating tape should be added for anti-freezing on the outdoor section.

4. Anti-freezing fluid addition: The concentration of the anti-freezing fluid should be configured according to the local minimum temperature. Regularly check the liquid level and pH value after the system is running.

5. Electrical connection: The controller, circulation pump, and auxiliary heat source should be on separate circuits. Install an earth leakage protection switch and ensure reliable grounding.

6. Pressure test: After installation, conduct a 1.2 MPa water pressure test on the water tank and the collector side separately. Maintain the pressure for 30 minutes without leakage. 

VIII. Application Cases

1. Residential: Installed a 150L double-pipe system. The flat collector was hung on the south balcony, the water tank was placed in the living balcony, and the auxiliary heat source was connected to a gas wall-mounted heater. The winter gas cost was reduced by 40%.

Hotel: Configured 200L double-pipe water tanks + 4m² flat collectors for guest rooms. The auxiliary heat source was an air-source heat pump. The annual operating cost was only 1/3 of pure electric heating.

Villa: 300L double-pipe system. The lower pipe was connected to a 20m² flat collector array, and the upper pipe was connected to a ground source heat pump. It met the needs of floor heating and domestic hot water. The owner reported that "there was no shortage of free hot water in summer".

Dormitory: 3 parallel 300L double-pipe water tanks. The auxiliary heat source was electric heating. It met the shower needs of 120 employees. In summer, it was completely free, and in winter, the electricity cost was 65% lower than that of pure electric water heaters. 

IX. Development Trends

1. Split-type becomes the mainstream: With the widespread adoption of high-rise residential buildings, split-type solar energy systems, due to their separate collectors and water tanks, as well as their flexible installation, have seen a continuous increase in market share.

2. Dual coil tubes/multi-energy complementation becomes popular: As users' demands for stable hot water throughout the year rise, the dual coil tube design, which allows for the connection of various auxiliary heat sources, has become a standard feature in mid-to-high-end products.

3. Upgrade of stainless steel inner tanks: By adding magnesium rods for protection and improving welding techniques, the lifespan of stainless steel inner tanks has been extended, making them the preferred choice for both economic and engineering markets.

4. Smart IoT: The controller integrates a Wi-Fi module, allowing users to view water temperature, set auxiliary heating periods, and receive fault alarms through a mobile app.

5. Standardization of balconies: For residential buildings, the combination of a collector and a small-capacity dual coil tube water tank (100-150L) forms a standardized product, which is easy to install.

Summary: The flat-panel split-type solar water heater (Split Solar Water Heater) has become the ideal energy-saving hot water solution for modern residences and small to medium-sized commercial spaces. We sincerely invite all distributors and engineering contractors to join hands and work together to explore the market! 

Contact us immediately to obtain the dual-pipe system solution and cooperation policies!