Solar Water Heaters Evacuated Tube Collector

Evacuated tubes are the absorber of the solar water heater. They absorb solar energy converting It into heat for use in water heating. Evacuated tubes have already been used for years in Germany, Canada, Chin and UK. There are several types of evacuated tubes in use in the solar industry. At Sunlit, we use the "Twin-Glass Tube" technology. This type of tube is chosen for its reliability and better performance.

Technical Specification

Length (nominal) 1800mm / 1500mm
Outer tube diameter 58 mm / 47 mm
Inner tube diameter 47mm / 37mm
Glass Thickness 1.6 mm
Thermal expansion 3.3x10-6 oC
Material Borosilicate Glass 3.3
Absorptive Coating Graded CU-N/CU)
Absorptance >92% (AM1.5)
Emittance <8% (80oC)
Vacuum P<5x10-3 Pa
Stagnation Temperature >200oC
Heat Loss <0.8W/ (m2oC)
Maximum Strength 0.8MPa

Insulated Storage Tank

Inner Tank Stainless Steel 304-L/Copper
Inner Tank Welding Seam Welding/Gas Welding
Turbulence Preventer Provided
Deep Drawn Dishes Provided
Outer Tank Stainless Steel 430 Grade / Coated sheet
Tank Side Dish Aluminum Powder Coated
Heat Retention 72 hours
Insulation PUF
Electrical Backup Provided ISI Make (Optional)
Supporting Stand MS Epoxy Coated


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Capacity No.of Persons Utility Points
100 LPD 3-4 Persons 1-2 points
200 LPD 5-6 Persons 3-4 points
300 LPD 6-8 Persons 5-6 points
500 LPD 10-12 Persons 7-8 points
  • Focusun Energy Systems :

  • Dr Jaganathan Nagar,

  • Opposite cmc Avinashi road,

  • Coimbatore 641 014.

  • Phone : +91 422 2591069

  • Mobile : +91 9842291069.

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