Double Pass Vacuum Tube Solar Air Collector

1. Product Overview: A New Generation of Solar Air Heating

The DVC Solar Air Collector represents a breakthrough alternative in modern solar heating technology. Unlike traditional solar thermal systems that depend on water or glycol as heat-transfer media, the DVC series uses air as the working fluid, eliminating the risks of freezing, leakage, corrosion, and pipe burst failures that have long troubled liquid-based systems.

By combining direct-flow double-pass vacuum glass tubes, high-performance interference coatings, and a patented expansion-joint inner tube structure, the DVC collector delivers stable heat output even under extreme conditions. These innovations address long-standing pain points such as tube cracking, freeze damage, and thermal shock—making it an ideal solution for schools, office buildings, industrial workshops, rural houses, agricultural drying rooms, and other heating or drying applications.

The DVC air solar heater harnesses sunlight to heat air directly, forming a clean, efficient, and maintenance-free heating system. Whether used for space heating or industrial drying, the system ensures fast temperature rise, strong airflow, low operational cost, and long service life. For regions with cold winters, high altitude, or unstable sunlight, the DVC air collector offers a reliable energy-saving solution that delivers consistent performance year after year.

2. Product Features: DVC500 Double-Pass Vacuum Tube Solar Air Collector

1) Innovative Architecture: Air-Based Heat Transfer for Maximum Safety

Revolutionary working medium:
Instead of circulating water, glycol, or other liquids, the DVC system heats air directly inside the vacuum tube. The heated air is then delivered indoors or to a drying chamber through a forced-air circulation system, either directly or via a plate heat exchanger. Without liquid media, the entire system becomes inherently safe—no boiling, no freezing, no scaling, and no pipeline corrosion.

Core structural innovation:
The specially engineered double-pass vacuum tube with an expansion-joint design enables smooth airflow from the tube inlet to outlet. The head-to-tail open structure significantly reduces airflow resistance, allowing higher volume of heated air per unit of fan power. This design prevents common failures such as freeze bursting, cold–hot stress cracking, and material fatigue.

2) Advanced Coating Technology: High Absorptance and Low Emittance

Each DVC vacuum tube adopts a premium magnetron-sputtered selective absorption coating featuring:

· Solar absorptance: 93% ± 2% (AM 1.5)

· Thermal emittance: 6% ± 2% at 80°C

The interference coating captures maximum solar radiation while minimizing thermal re-radiation losses. Combined with the vacuum insulation layer, the tube maintains extremely high thermal efficiency even during cloudy days, high-altitude operation, or low-ambient temperatures. Under typical conditions, the system achieves over 80% solar-to-thermal conversion efficiency, outperforming many conventional air heaters.

3) Extreme Durability: A Lifespan of Over 50 Years

Wide operating temperature range:
The DVC air collector can withstand temperatures above 280°C, enabling use in industrial and agricultural drying systems. Because the working medium is air, not water, the system remains unaffected by freezing, ensuring consistent performance even in regions with harsh winters or severe temperature fluctuations.

Structural protection:
The inner expansion-joint design eliminates thermal stress and accommodates rapid temperature changes, preventing tube cracking or deformation. With no liquid inside the system, there is no risk of corrosion, scaling, leakage, or internal pressure build-up. Routine maintenance is essentially unnecessary, giving the collector an ultra-long service life exceeding half a century.

4) Multi-Energy Integration: Perfect Coupling with Heat Pumps

For ultra-cold regions, the DVC air collector can be integrated with an air-source heat pump. During daytime operation, the collector preheats the outdoor air, effectively improving the heat pump’s COP in low-temperature conditions. This hybrid approach reduces power consumption, minimizes defrosting cycles, and ensures stable, all-season heat supply, even when winter temperatures drop far below zero.

3. Four Core Advantages: Creating a True Competitive Edge

1) Double-Pass Vacuum Tube Design: Low Resistance, High Airflow

The unique straight-through structure reduces airflow resistance by more than 30% compared with conventional air tube collectors. With the same fan power, the DVC collector delivers significantly higher air volume, ensuring faster temperature rise and uniform heat distribution.

The optimized tube geometry prevents internal dust accumulation, maintains clean airflow channels, and prevents hot/cold zones—improving system stability and heating comfort.

2) Exceptional Heat Collection Efficiency: Lower Costs and Higher Output

Thanks to the interference absorption layer and magnetron-sputtered coating, the system’s thermal conversion efficiency reaches 80% or higher, compared with 60–70% for standard air collectors. This translates directly into:

· lower electricity consumption

· shorter payback periods

· reduced reliance on fossil fuels

· significant operational savings over time

Since no fuel or water is consumed, the DVC system becomes an eco-friendly, economical heating option for both residential and commercial applications.

3) All-Scenario Adaptability: Safe and Reliable in Harsh Environments

The collector is engineered for stability across a wide range of climate conditions:

· High temperature tolerance: up to 280°C

· Extreme cold resistance: unaffected by freezing

· High-altitude stability: withstands strong UV and low pressure

With no liquid medium to freeze, expand, or corrode equipment components, the collector offers true “set-and-forget” operation—ideal for remote sites, industrial facilities, and long-term heating projects.

4) Eco-Friendly Manufacturing: High-Quality and Sustainable

The DVC series utilizes German constant-temperature integrated foaming technology with high-pressure, eco-friendly polyurethane insulation. This process creates a uniform, dense insulation layer with excellent mechanical strength and weather resistance. The materials contain no harmful substances, supporting sustainable development and green building standards.

4. Application Scenarios: Meeting Diverse Heating and Drying Needs

The system’s high adaptability and pure-air design make it suitable for nearly all heating or drying environments, especially in regions with large seasonal temperature differences.

5. Why Choose the DVC Solar Air Collector?

· Total solution to freezing and cracking problems: No liquid medium, zero freezing risk, no leakage or scaling.

· Superior thermal performance: With >80% solar-to-thermal efficiency, the system significantly reduces energy consumption.

· Ultra-long lifespan: The vacuum tube and structural components are designed for 50+ years of operation.

· All-application flexibility: Compatible with heating, drying, agricultural processing, and hybrid heat pump systems.

· Reliable in extreme climates: Performs consistently in low temperatures, high altitudes, and strong solar radiation.

The DVC Air Collector leverages cutting-edge solar thermal technology to redefine the future of solar heating. With its stability, safety, and energy-saving performance, it supports global carbon-reduction goals and brings long-term value to commercial, industrial, and residential users.

6. Soletks Group Advantages

1) R&D Capability: Global Leadership in Solar Thermal Innovation

· Over 117 core patents in collector design, coatings, and system integration

· Among the few manufacturers worldwide mastering both BlueCore selective coating and black coating production

· Continuous breakthroughs in high-temperature solar thermal technology

2) Intelligent Manufacturing: Industry 4.0 Production Strength

· Six major production bases

· One collector produced every 55 seconds

· Full-chain quality control from raw materials to final assembly

· CE-certified products meeting European and global standards

3) Full Industrial Chain Integration: Comprehensive Service Capability

· Independent production of all core components

· Strength across materials, manufacturing, system design, project engineering

· Solutions covering 30+ industrial, commercial, agricultural applications

· End-to-end project support: survey → design → installation → commissioning

4) Global Recognition: Trusted by Customers in 40+ Countries

· World’s second-largest flat plate collector manufacturer

· Strong market presence across Europe, Latin America, Africa, and Asia

· Total CO₂ reduction: 16.7 million tons, equivalent to planting 700 million trees

· Recognized as a national “Solar Thermal Efficiency Leader” enterprise

Contact Us

For technical consultation, distributor cooperation, or project quotation:

Email: export@soletksolar.com
Website: www.soletksolar.com
Headquarters: Soletks Group, China