10 Best Natural Gas Tankless Water Heater of December 2025

• Endless hot water for your entire home
• V65eN HE High Efficiency Tankless Hot Water Heater - Natural Gas: Outdoor Installation Only
• Up to 6.5 GPM hot water flow rate (varies by groundwater temp)
• Control-R 2.0 mobile app features timers and schedules throughout the day and allows you to remotely put the system into vacation mode.
• Residential Factory Warranty - 120 months (heat exchanger), 12 months (labor), 60 months (parts)

Rinnai

• [Ease to Use] For whole home on demand indoor use with safe, efficient power ventilation , perfect for any small homes, cabins or apartments.
• [Modern Design] Exclusive color digital temperature display for easy to read.
• [Saving More Energy] Eco and Full gas switch for energy saving and get ideal hot water temperature.
• [More Safety] Flame-out protection, anti-freezing protection, over-heating protection, air flow pressure switch protection to ensure the safety.
• [Controls Water Temperature Easily ] Uses standard 1/2" NPT water fittings and is equipped with easy to use manual water temperature controls.

CAMPLUX ENJOY OUTDOOR LIFE

• Exclusive Water Savings technology conserving up to 1, 100 gallons per year
• 157, 000 BTU (gas consumed per hour)
• Exclusive Hot Start Programming minimizes cold water burst by staying in ready-fire state
• Recirculation pump ready kit ready
• For use outdoors with freeze protection up to -30 degrees
• Fuel Type: Natural Gas

Rheem

• Natural Gas Tankless Water Heater
• Direct Vent Indoor
• 8.4 gal/min. at 35-Degree Rise
• UMC-117 remote control and 10-Feet of thermostat wire is included
• Low Nox Version

Rheem

• Lifetime warranty
• Save up to 60-percent on your water heating cost with an ECOSMART electric tankless water heater
• Never run out of hot water with an ECOSMART tankless water heater
• Patented Self Modulating Technology and design
• ECOSMART tankless water heaters are 99.8-percent energy efficient.Uniform Energy Factor:0.98

Ecosmart

• RU199iN Sensei SE+ Super High Efficiency Tankless Hot Water Heater - Natural Gas: Indoor Installation Only
• Up to 11 GPM hot water flow rate (varies by groundwater temp)
• 15,000 BTU (Minimum) / 199,000 BTU (Maximum)
• Circ-Logic technology allows you to set recirculation patterns that coincide with your typical habits. Hot water is available when you need it!
• Endless hot water for your entire home
• Residential Factory Warranty - 120 months (heat exchanger), 12 months (labor), 60 months (parts)

Rinnai

• Modulates heat output in response to the flow rate of water running through the unit.
• Power vented directly vertically (rooftop) or sideways (wall) via Stainless Steel CAT III Flue 3.5" Diameter Included (20")
• NATURAL GAS - European Model - Digital Display is in Celsius
• Delivers 6.6 gpm of hot water with a 35°F Instant Temperature Rise (Equivalent to 5.5gpm with a 45F temp Rise)
• Certified for Installation in Manufactured (Mobile) Homes Pure Copper Heat Exchanger

GASFLEX

• Whole home indoor, gas powered tankless water heater, rated at 3 GPM that activates only on demand and no pilot light needed, reducing energy consumption
• Sleek, modern design with black tempered glass front panel featuring an easy to use LED display controls
• Features fully automatic temperature controls with an energy saving mode and child lock technology
• Safe electronic ignition system; Plugs into standard 110v electrical outlet with UL-listed cord. Field tested to 5500 ft. elevation (not recommended to be used any higher)
• Uses standard 1/2" NPT water fittings and comes with horizontal venting allowing for a convenient and quick installation

Eccotemp

• V65iN HE High Efficiency Tankless Hot Water Heater - Natural Gas: Indoor Installation Only
• Up to 6.5 GPM hot water flow rate (varies by groundwater temp)
• Control-R 2.0 mobile app features timers and schedules throughout the day and allows you to remotely put the system into vacation mode.
• Endless hot water for your entire home
• Residential Factory Warranty - 120 months (heat exchanger), 12 months (labor), 60 months (parts)

Rinnai

• Endless hot water
• Ideal for outdoor applications
• High Efficiency
• Low Nox

Noritz