The 3kW heating element is standard for instant geysers in India, but you should check the type and material of the heating element. Incoloy or copper heating elements are known for their durability and efficiency. Otherwise glass coated heating elements are the best. Only AO Smith provide glass coated heating element in Instant geysers in India.

Instant geyser must have safety features like a thermostat to prevent overheating and a pressure relief valve to release excess pressure. As the 3kw is considered high power which put a lot of load on wiring of the house specially old houses with decade old wiring. An ELCB inbuilt instant geyser are also need of the hour to avoid electric shock. Better to connect elcb plug/top separately to geyser.

Racold Pronto Pro 3L 3KW Vertical Instant Water Heater (Geyser) | Faster Heating | Suitable for High Rise Buildings | Italian Design|3 Levels of Safety|Convenient for Kitchen & Bathroom Applications
  • PUF INSULATION: the dense and thick insulation in the tank effectively retains heat, improving energy efficiency and lowering electricity costs
  • FASTER HEATING: the high-capacity heating element ensures rapid access to hot water
  • AUTO CUT OFF: the stem-type thermostat and cutout feature provide automatic temperature control and added safety for your water heater
  • NO BACK FLOW: the anti-syphoning system prevents water from flowing back into the container, thus avoiding dry heating
  • HIGH PRESSURE RESISTANCE: the water heater has high pressure withstanding capacity, which makes it suitable for high-rise buildings and high pressure pump applications
Racold Svelto 3L 3KW Vertical Instant Water Heater(Geyser) White | Free Electric Plug | Faster Heating |3 Levels of Safety |Italian Design| Convenient for Kitchen & Bathroom Applications
  • High Pressure Resistance: Your water heater has high pressure withstanding capacity, which makes it suitable for high-rise buildings and high pressure pump applications
  • Safety Plus: Three levels of safety against high temperature and pressure, provided by a hightech adjustable thermostat, cut-out and multi function safety valve according to international standards
  • Faster Heating: The high power heating element ensures you get hot water in minimum time
  • Anti-Siphon : The back flow of the water from cold inlet pipe is prevented by anti-siphoning system from inner tank of the water heater,Avoids dry-heating incase of no or less water inside inner tank due to back flow of water
  • Rust Proof Body : This water heater have rust proof body to prevent corrosion leaving no room for rust, ensuring, also its longer life Improves aesthetics in the bathroom
Black+Decker Galerus Geyser 3 Litre | Instant Water Heater for Home & Kitchen | 3KW | High Grade Stainless Steel Tank I Copper Sheathed Heating Element I 5 Year Tank Warranty | Water Geyser White
  • ★【3L Compact Capacity】: Ideal for kitchens and small water usage areas.
  • ★【3KW High-Speed Heating】: Ensures instant hot water with superior efficiency.
  • ★【Stainless Steel Tank】: Built with high-grade stainless steel for long-lasting durability.
  • ★【Copper Sheathed Heating Element】: Offers rapid heating and corrosion resistance.
  • ★【5-Year Tank Warranty】: Guaranteed durability with extended tank warranty.
Crompton Solarium Neo 3-Litre, 3KW Instant Water Heater/Geyser with Rust Free ABS Body (Ivory)
  • PRODUCT: Crompton’s energy efficient instant water heater with rust proof ABS body
  • TECHNICAL SPECIFICATIONS: Wattage: 3000 W; Capacity: 3L; Pressure 6.5 bar
  • 4 LEVEL SAFETY: Capillary Thermostat, automatic thermal cut-out, pressure release valve and fusible plug
  • ANTI-SIPHON PROTECTION: Designed to prevent any backflow of water and protect the heating element from dry heating damage
  • QUALITY COMPONENTS: ISI marked nickel coated special element to provide resistance against scale formation
NEXOMS Cup Type Heating Element ISI Marked 3KW Compatible for 3 Litre – 6 Litres Instant Geysers
  • Tube Material: Anti-Corrosive Copper
  • Power: 3KW
  • Heavy Quality ISI Marked Element
  • Compatible for Portable Geysers and Instant Geysers 3 Litre to 6 Litres
POLYCAB Intenso 3 litre, 3 KW Electric Instant Geyser (Water Heater) For Home & Kitchen | Efficient Heating Element | Enhanced Safety Measures | 5 years tank & 2 years product warranty【White】
  • ✅【Efficient Heating Element】Experience instant hot water with the highly efficient heating element.
  • ✅【Special Grade Heating Element 】Rapid heating, extended tank durability. Efficient performance meets lasting reliability.
  • ✅【Advanced 5 layers safety】 Advanced Thermostat and Thermal Cut-off. Advance Pressure Release Value. Anti-Siphon Protection. Shock-proof Plastic outer body. Multi-Layered Protection against Corrosion.
  • ✅【Versatile Usage】 POLYCAB’s compact Water Heater design is perfect for both Bathroom & Kitchen applications.
  • ✅【Durable Engineered Plastic Body】Our Water Heaters boasts a rust-proof engineered plastic body that ensures prolonged durability.
AO Smith EWS Plus Black Instant Water Heater 3 Litre with 3kW Incoloy Heating Element | 2X Corrosion Resistant Blue Diamond Glass Tank | Instant Geyser for Kitchen & Bathroom | 5-Year Tank Warranty
  • SLEEK DESIGN FOR YOUR KITCHEN AND BATHROOM: Elevate your space with the AO Smith geyser 3 litre. Its sleek and modern design seamlessly blends into any kitchen or bathroom, making it the perfect kitchen geyser 3 litre for compact spaces and stylish homes.
  • CORROSION RESISTANCE FOR HARD WATER DURABILITY: Designed to last, this 3 litre geyser features a Blue Diamond glass-lined tank that resists corrosion even in hard water. Trust the durability of this electric geyser 3 litre to provide years of reliable performance.
  • RAPID HEATING FOR INSTANT COMFORT: Enjoy hot water on demand with the instant geyser 3+ litre. Its advanced glass-coated heating element ensures quick and efficient heating, making it an ideal kitchen instant water heater for busy mornings.
  • PERFECT FOR HIGH-RISE APARTMENTS: Built tough, this geyser 3 litre is perfect for high-rise living with its 8 Bar pressure rating and heavy-duty 2mm tank. Whether as a kitchen geyser or a small geyser for bathroom, it handles high-pressure needs effortlessly.
  • SAFETY YOU CAN TRUST FOR YOUR FAMILY: Stay worry-free with the AO Smith geyser 3+ litre, offering 5-level safety protection. This includes an ISI power cord, pressure relief valve, and shockproof outer body, ensuring your geyser kitchen is safe for everyone.
AO Smith EWS-5 White Instant Geyser 5 Litre With 3kW Express Heating | High Rise Building Bathroom & Kitchen geyser | UL Rated Wiring & Pressure Relief Valve For Ultimate Safety | 5 Year Tank Warranty
  • INSTANT HOT WATER HEATER FOR YOUR HOME: Experience the comfort of instant water heater technology with our 3000-watt element. Whether for your bathroom or kitchen, this instant water heater delivers hot water in seconds, perfect for cold mornings.
  • DURABLE STAINLESS STEEL GEYSER 5 LTR: Our geyser 5 litre with a stainless steel tank is built to resist corrosion even in hard water. Designed for long-lasting performance, this 5 litre geyser ensures you enjoy dependable hot water every day.
  • ADVANCED SAFETY FEATURES FOR YOUR FAMILY: Stay protected with our electric geyser featuring a 5-level safety shield. From overheating control to a rust-proof body, this instant water heater for bathroom guarantees total peace of mind for you and your loved ones.
  • HIGH-PRESSURE READY FOR HIGH-RISE HOMES: Perfect for high-rise living, our water heater 5 litre handles up to 6.5 Bar pressure effortlessly. This hot water geyser for bathroom ensures consistent performance, even in multi-story buildings.
  • WORRY-FREE WARRANTY FOR YEARS TO COME: Invest in confidence with a 5-year tank warranty and 2-year product warranty by AO Smith. Our instant water heater is backed by comprehensive coverage, ensuring you get the best experience without worry.
Crompton InstaBliss 3-L Instant Water Heater (Geyser) with Advanced 4 Level Safety (White), Wall Mounting
  • Rust Proof Outer Body: High quality Thermoplastic engineering prevents rusting of the outer body
  • Food Grade Inner Tank: 304 Grade Stainless Steel Inner Tank; also suitable to be used in the kitchen
  • Powerful Heating: 3000-Watts Copper Heating Element for 33% faster heating
  • 4-Level Safety: Thermostat, automatic thermal cut-out, pressure release valve and a fusible plug to ensure complete safety
  • Withstands a pressure of 6.5 Bar: Suitable for high rise buildings and pressure pump applications

Another thing to check is pressure bar capacity of inner tank specially if you like high rise buildings as water pressure can be much more for tank to withhold. You can also consider 4.5kw instant geysers if the house is fairly new with new wiring.