100L‑150L‑200L‑250L‑300L Roof Mounted Passive Solar Hot Water Heater
Roof‑mounted passive solar hot water heater adopts integrated compact thermosyphon design, both storage tank and solar collectors are installed on rooftop. It works by natural hot‑cold water density difference without circulation pump or external power supply, low failure rate and easy maintenance. Multiple capacity options from 100L to 300L fully satisfy domestic bathing, laundry and kitchen hot‑water demands for different‑size families. Optional electric auxiliary heating guarantees continuous hot‑water supply during cloudy‑rainy and low‑sunlight weather, ideal for residential rooftop solar hot‑water projects。
Working Principle
- Solar collectors absorb solar irradiation and convert sunlight into heat to warm the water inside collector channels.
- Hot water with lower density rises and accumulates in upper section of storage tank; cold water with higher density flows down into collectors. Continuous natural thermosyphon passive circulation is formed without any pump or electricity consumption。
- This is non‑pressurized gravity‑type system. Hot‑water flows out by water‑head height difference. It cannot be directly connected to high‑pressure municipal tap‑water to avoid tank damage. Matching elevated water tank is required for water supply.
- When solar irradiation is insufficient, optional built‑in electric heating element automatically supplements heat to secure stable hot‑water output for household daily usage.
Important note: Whole unit shall be mounted on load‑bearing rooftop. Anti‑freezing pipeline insulation is compulsory in frost‑prone regions. Magnesium sacrificial anode rod is consumable spare‑part and needs regular inspection and replacement. System must cooperate with gravity water supply mode, forbidden for direct mains pressure connection.
Core Technical Specifications
‑ Available Tank Capacity: 100L /150L /200L /250L /300L ‑ Inner Tank Liner: SUS304‑2B / SUS316L food‑grade stainless steel; replaceable magnesium sacrificial anode rod ‑ Insulation: 45‑55 mm high‑density closed‑cell PU integral foaming, reduce long‑time standby heat loss ‑ Working Pressure: Non‑pressurized gravity working condition ‑ Solar Collector: Evacuated vacuum tube / flat‑plate collector optional, high‑efficiency selective absorber coating ‑ Circulation Mode: Natural thermosyphon passive circulation, no circulation pump required ‑ Auxiliary Heating: Optional 1500‑3000W built‑in electric heating element ‑ Outer Casing & Bracket: Color‑coated galvanized steel / stainless‑steel heavy‑duty anti‑rust rooftop mounting frame ‑ Typical Service Life: 12‑18 years under standardized routine maintenance ‑ Certifications: CE, ISO9001 available for export shipments
Application Scenarios
‑ 100‑150L: 2‑4‑person small‑size family domestic hot‑water ‑ 200‑300L: 4‑7‑person large‑size family residential hot‑water ‑ Flat / sloped rooftop installation, rural housing, residential energy‑saving renovation projects ‑ Mild‑climate zones, regions equipped with gravity water‑supply system
Collectors require minimum 4‑6 hours effective direct sunlight daily. Keep away from shading of trees and surrounding buildings. Rooftop load‑bearing capacity shall be confirmed before installation.
| Feature | Roof‑Mounted Passive Solar Hot Water Heater | Split Pressurized Solar Water Heater |
|---|---|---|
| Installation Layout | Tank + collectors both installed on rooftop | Collectors outdoor, tank placed indoors |
| Circulation | Passive thermosyphon, no pump, no power needed | Pump‑driven forced circulation, need power supply |
| Water Supply | Gravity water‑head outflow only | Directly connect municipal tap‑water |
| System Cost | Cost‑effective for household | Higher investment |
| Maintenance | Simple structure, low failure rate | More components, higher maintenance requirement |
Key Buying Considerations
- Rooftop load‑bearing: Check roof bearing capacity before installation for full‑water unit safety.
- Water‑supply condition: Non‑pressurized model relies on gravity water head, strictly prohibit direct connection with municipal high‑pressure tap‑water.
- Climate adaption: Pipeline anti‑freezing insulation must be completed in frost‑prone areas.
- Tank material: SUS316L liner recommended for coastal salt‑spray and high‑hard‑water‑quality locations, confirm magnesium anode rod included.
- Quotation confirmation: Verify complete set including tank, collectors, bracket, sealing fittings and optional electric heating.
- OEM support: Custom tank capacity, collector quantity and brand logo for bulk export orders.
- Export compliance: Provide CE & ISO9001 certification documents for overseas customs clearance.
Installation & Routine Maintenance
Installation shall be finished by professional solar installers. Adjust collector tilt angle according to local latitude. Never activate electric heating before tank is fully filled with water.
‑ Every 3‑6‑month inspection: Clean dust on collector surface; inspect pipe joints for water leakage. ‑ Every 1‑2‑year professional service: Replace exhausted magnesium anode rod; clean tank internal sediment; check bracket anti‑rust condition.
FAQ
Q: What are the main advantages of roof‑mounted passive solar water heater?
A: Natural thermosyphon passive circulation without pump and power consumption, simple structure, low failure rate and competitive price. Whole set is pre‑assembled for convenient rooftop installation, perfect for family gravity‑supply hot‑water usage.
Q: Can I connect this unit directly to city tap‑water?
A: No. It is non‑pressurized gravity‑type equipment. Direct connection with mains high‑pressure tap‑water will cause tank deformation or damage. Elevated gravity water tank is required.
Q: How does it perform in winter?
A: Collectors work well under sunshine. Water pipelines must be wrapped with anti‑freezing insulation material to prevent pipe freeze‑cracking in cold nights.
Final Conclusion
100L‑300L Roof Mounted Passive Solar Hot Water Heater is economical integrated rooftop solar hot‑water solution for household application. Adopting natural thermosyphon passive circulation without pump, it realizes low‑failure‑rate solar water heating. Multiple‑capacity options cover different‑size‑family hot‑water requirements. Optional electric heating ensures hot‑water output in bad‑weather conditions. Please note it belongs to non‑pressurized gravity‑type product, cannot bear municipal tap‑water pressure. Rooftop load‑bearing check, matched gravity water‑supply and regular maintenance are essential for long‑term stable running.
