What is the right size and how do you select one?
It’s crucial to figure out the size of tankless water heater you require. A heater that is too tiny won’t be able to supply your home with enough hot water, while a heater that is too big will cost you money you don’t need to spend. How much water will you need when there is high demand, such as when a load of laundry is being washed, the kitchen tap is running, and you are having a shower? How much water will be required to meet the demand? Before investing in a tankless water heater, you should take into account the flow rate or the amount of water used by a fixture or appliance measured in gallons per minute (GPM).
The average Gallons Usage for Common Fixtures and Appliances
| Appliance/Device | Household per Day | Percent of Total |
| Toilet | 33 gallons | 24% |
| Shower | 27 gallons | 20% |
| Faucet | 27 gallons | 20% |
| Washing Machine | 22 gallons | 16% |
| Leaks | 18 gallons | 13% |
| Bath | 4 gallons | 3% |
| Other | 4 gallons | 3% |
| Total | 138 gallons | 100% (99% with rounding) |
Based on the above figures you can figure out or have an estimate of how much water you need on a day-to-day basis.
Calculations
An average tankless water heater consumes 9–12 kWh. With that information we can calculate the total cost of electricity = total KWH used × per unit cost.
Electricity prices in your State
When do you need a tankless water heater?
A tankless water heater will be 20% to 40% more efficient if your hot water usage is little (less than 41 gallons per day). A tankless water heater is 8% to 15% more energy efficient if you use a lot of hot water (86 gallons per day on average).
Zanskar water heater
Zanskar provides performance-driven tankless or on-demand geysers for household bathrooms, kitchens, and all hot water needs. We also provide on-site free demo and installation with a price starting from Rs. 9,990 onwards. Our products are globally certified in performance and safety. We provide energy savings of up to 25% to 50%. The waiting period is less than 10 seconds with an unlimited hot water supply. Our products are compact and flexible to install, hence saving a lot of space in any household.