Buying a Tankless Water Heater 101

By: Smart Zero Home
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Tankless water heaters can be an excellent replacement or backup option for ypur existing stoage water heaters. Tankless water heaters, save energy and space, and provide a lot of flexibility to meet your hot water needs.

Considerations when buying a tankless water heater:

1) Size: The ideal size for your tankless water heater is driven by your needs. A tankless water heater is sized by its flow rate (gallons per minute), and the delta by which it can heat the water (difference of the water heater’s output water’s temperature and the water temperature supplied to the water heater) for a specific flow rate.

2) Efficiency & Energy Factor: A tankless water heater’s efficiency is measured by its Energy Factor (EF). Energy Factor is the total energy utilized (percentage of input energy) by the water heater to heat the water. Thus a water heater with a Energy Factor of 0.92 is 92% efficient and can utilize 92% of the input energy.  See the EF recommendations from our design generator.

Tankless water heaters save energy, space, and water compared to a storage water heater

3) Electric vs. Gas: An electric tankless water heater is almost 30% cheaper, (also cheaper to install). An electric tankless water heaters is also more efficient - upto 98% efficient (compared to gas ones topping at 85%), and are easier to maintain and operate. A gas tankless water heater uses a cheaper fuel and is thus cheaper to operate.

4) Main or Supporting Role: In larger homes, the tankless water heater may not be able to meet the higher simultaneous usage (higher GPM flow rates needed), and therefore 2 or more tankless water heaters may be needed (smaller ones including point-of-use water heaters for specific usage). A tankless water heater can also be used with an existing storage tank water heater or solar water heater. Smaller point-of-use tankless water heaters can be used separately in high and important usage areas such as the kitchen and master bathroom.

You can get tankless water specifications customized for your home from our intelligent design generator.

See the top 5 tankless water heaters available in the market today for your home.