ETC Evacuated Tube Solar Water Heaters
High-efficiency vacuum tube solar water heaters engineered with 3-layer borosilicate glass, PUF thermal insulation, and scale-guard protection for hard water conditions.
Maximum Thermal Absorption, Even on Cloudy Days
ETC (Evacuated Tube Collector) Solar Water Heaters are built using concentric three-layered evacuated borosilicate glass tubes. The vacuum between outer and inner glass provides near-total thermal insulation, eliminating conductive heat loss to cool ambient air.
The inner tube is coated with high-grade multi-layer absorption materials that capture both direct and diffused sunlight. Water circulates naturally via thermosiphon dynamics, providing abundant steaming hot water (65°C – 85°C) for your entire family year-round.
Scale Guard for Hard Water
Borewell and hard water with high mineral TDS can cause scaling in ordinary heaters. Naesara ETC systems feature sacrificial anode scale guard protection and non-stick internal lining to prevent mineral crust build-up.
Key Performance Benefits
A cost-effective, long-life hot water solution requiring zero electricity.
Save Up to 70% on Power Bills
Water geysers consume massive electric power during peak morning hours. ETC solar heating eliminates this major electric expense with a 1 to 2 year ROI.
Scale Guard Protection
Equipped with sacrificial anode and smooth anti-adhesion inner finishes specially formulated for Bangalore and South Indian borewell water conditions.
Cloudy Weather Readiness
High-absorption selective chemical coatings capture diffused UV and infrared radiation on overcast monsoon days, keeping storage water hot.
20+ Years Lifespan
Built with SS304/SS316 food-grade stainless steel tanks, heavy mild-steel powder coated frames, and borosilicate 3.3 vacuum glass tubes.
Technical Specifications & Tube Configurations
Precision manufacturing ensuring leak-proof operation and minimal heat radiation loss.
System Specifications
- Vacuum Tube Outer Diameter: 58 mm
- Vacuum Tube Inner Diameter: 48 mm
- Vacuum Tube Standard Length: 1800 mm (2100 mm for 500L)
- Outer Tank Diameter: 480 mm
- Inner Tank Diameter: 380 mm
- Tank Insulation: 50 mm High-Density PUF (Polyurethane Foam)
- Operating Temperature: 65°C to 85°C
- Inner Tank Options: SS304, SS316, Galvanized Steel, CRCA with protective non-stick coating
- Outer Tank Cladding: Galvanized Pre-coated & Stainless Steel
- Mounting Stand: Mild Steel, high-grade anti-corrosive powder coating
- Grommets & Seals: Heat-resistant Food Grade Silicon Rubber
- Circulation Principle: Natural Thermosiphon Circulation
- Optional Backup: 1.5 kW or 2 kW electrical heating backup (optional)
Capacity & Tube Sizing Table
Select the optimal capacity according to the number of family members and daily hot water usage:
| Capacity | Tubes (58mm) | Recommended For |
|---|---|---|
| 100 LPD | 10 Tubes × 1800mm | 2 – 3 Members |
| 150 LPD | 15 Tubes × 1800mm | 3 – 4 Members |
| 200 LPD | 20 Tubes × 1800mm | 4 – 6 Members |
| 250 LPD | 25 Tubes × 1800mm | 5 – 7 Members |
| 300 LPD | 30 Tubes × 1800mm | 7 – 9 Members |
| 500 LPD | 34 Tubes × 2100mm | Villas, Hostels & Hotels |