Evacuated Tube Collector
ETC Solar Water Heater
Non-pressurised domestic systems with high-temperature variants. Efficient even on cloudy days and easy to maintain.
- Capacity 100 L – 500 L
- Collector Evacuated tube
- Use Domestic
Overview
An ETC (Evacuated Tube Collector) solar water heater uses rows of double-walled borosilicate glass tubes, each holding a vacuum that traps the sun’s heat with almost no loss. It is the most popular domestic solar water heater in India — affordable, efficient in cold and cloudy weather, and simple to maintain.
Surya Urja’s ETC systems run on the thermosiphon principle: as the water in the tubes warms it rises naturally into an insulated storage tank, giving you hot water by morning with no pump and no running cost.
Highlights
Why it stands out
The engineering details that make the ETC Solar Water Heater a dependable, long-term choice.
Vacuum-tube efficiency
Evacuated tubes cut heat loss to near zero, so they keep performing on overcast days and right through winter.
Up to 80% lower bills
Free solar heat replaces most of your electric geyser or gas load — year after year.
Zero running cost
Passive thermosiphon flow moves the water — no pump and no electricity required.
Easy to maintain
Individual tubes can be cleaned or replaced without disturbing the rest of the system.
Optional electric backup
An inline backup element with thermostat guarantees hot water through long monsoon spells.
Hard-water variants
High-temperature and hard-water-tolerant configurations available for India’s varied water.
Specifications
Technical specifications
System
- Capacity
- 100 L – 500 L (domestic)
- Collector
- Evacuated tube (ETC)
- Circulation
- Thermosiphon (non-pressurised)
Build
- Tubes
- Borosilicate 3.3, double-wall vacuum
- Storage tank
- PUF-insulated, SS / glass-lined inner
- Stand
- GI / powder-coated
Performance
- Water temperature
- Up to 60–80 °C
- Backup
- Optional electric element
- Standards
- Built to MNRE norms
Specifications are indicative and configured to your requirement. Ask for exact specs →
Scope of supply
What's included
- Evacuated-tube collector array
- PUF-insulated storage tank
- GI mounting stand
- Cold-water feed tank & float valve
- Insulated inlet/outlet piping
- Optional electric backup heater
Final scope depends on site conditions and capacity. We confirm everything during the survey.
Applications
Where it's used
From a single installation to a large project, the ETC Solar Water Heater suits a wide range of settings across homes, institutions and industry.
- Homes & bungalows
- Apartments (per-flat)
- Hostels & PG accommodation
- Small hotels & guest houses
- Hospitals & clinics
- Gyms & salons
Assurance
The Surya Urja standard
- Certified components, built to standard
- Savings of up to 80% on energy bills
- All-weather performance, built for India
- Low-maintenance, long service life
- 5-year manufacturer warranty*
Manufactured in Anand, Gujarat · installed and serviced by our own team.
FAQ
Questions, answered
ETC or FPC — which should I choose?
ETC is more efficient in cold and cloudy weather and costs less, ideal for homes. FPC handles pressure and hard water better and suits hotels and industry. We recommend based on your water and usage.
What happens on rainy days?
Evacuated tubes still capture diffuse light, so you get useful heat. For back-to-back overcast days, the optional electric backup keeps water hot.
How many litres do I need?
Budget about 50–60 litres of storage per person per day. A family of four is typically served by a 200 L system.
Does hard water damage it?
Scaling can affect any heater. We offer hard-water-tolerant variants and recommend periodic flushing; a softener helps in very hard-water areas.
Explore
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Request a quote for the ETC Solar Water Heater
Tell us your requirement and our engineers will size the right system and share pricing — no obligation.