Green Region
51-60 °F

Tankless Water Heater Recommendations for Regions with Temperatures Between 51-60 °F

We have taken some top tankless water heater manufacturers and evaluated them for several different criteria. Based on the criteria listed below, here are the best tankless water heaters to purchase.

  • Customer Satisfaction – This is determined by the total of reviews and stars received from various review sites.
  • Price – Just because something is expensive does not mean it’s worth buying. Price is a major determining factor for most consumers when making a purchase. So, we evaluated a product on its price compared to other similar products on the market. Based on price, we rated each with a “Great Value”, “Average”, “Expensive.”
  • Energy Factor – Energy Factor (EF) is a measurement that is used to describe the energy efficiency of a water heater. To calculate a water heater’s energy factor, you take the amount of energy the water heater puts to use and divide it by the total amount of energy that goes into powering the unit.
  • GPM – Gallons Per Minute is one of the most important factors when considering a tankless water heater. If the GPM is too low, then you will be unable to run appliances and showers simultaneously. It is important to understand this when selecting a tankless hot water heater because it won’t be able to keep up with your household needs.
  • Product Features – Some tankless water heaters have added features that add value to their products. Some examples of these are built-in maintenance alerts, product warranties longer than the industry standard, quality of materials used to manufacture their product, and any safety features to name a few.

The best point of use tankless water heater

Stiebel Eltron Single Point-of-Use Water Heater – DHC

Customer Satisfaction – 4.7
Price – Expensive
Energy Factor – 0.97
GPM – .26 minimum flow
Features – No Venting Required, Self Modulating

The best electric tankless water heater

Stiebel Eltron Tankless Water Heater – Tempra 36

Customer Satisfaction – 4.6
Price – Average
Energy Factor – 0.98
GPM – 7.5 GPM
Features – No Venting Required, Self Modulating, 7-year Warranty

The best gas tankless water heater

Rinnai RU199in – 11 GPM

Customer Satisfaction – 4.8
Price – Expensive
Energy Factor – 0.96
GPM – 11 GPM
Features – Warranty: 120 months (heat exchanger), 12 months (labor), 60 months (parts), Flame Failure Protection, Boiling Protection, Combustion Fan RPM Check, Over Current – Glass Fuse, and Automatic Frost Protection.

The best commercial tankless water heater

Rinnai CU Series Commercial Tankless Gas

Customer Satisfaction – 5
Price – Expensive
Energy Factor – 0.97
GPM – 11 GPM
Features – Maintenance alerts, multiple venting options, built-in freeze control, 8-year warranty.


Tankless Water Heaters are Vulnerable to the Problems Hard Water can Cause

Protecting your tankless water heater from hard water scale is very important. You can protect your unit by cleaning the unit manually at least once a year or you can simply attach a HydroFLOW device around the cold water line going into the tankless water heater. From the moment you plug in the HydroFLOW device your tankless water heater will be protected all year. You will also get the added benefit of killing bacteria, algae and reducing corrosion throughout your entire plumbing system.
For more detailed information about tankless water heaters please read our blog:
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