Best Natural gas Tankless water Heaters
The Stiebel includes specialized volt inputs for both hot showers and Roman jacuzzi tubs.
Eccotemp FVI-12-NG High Capacity Gas Tankless Water HeaterThe Eccotemp FVI-12-NG Gas Tankless Water Heater has a flow rate of 3.4 GPM and a BTU rating of 74, 500. While BTUs are often quoted as "heat, ” a BTU is actually the amount of energy needed to cool or heat one pound of water by one degree Fahrenheit. In practical terms, most people find BTUs are good for comparison rather than as a specific measure.
The Eccotemp is designed for small and medium-sized homes. Considering the fact that a shower uses approximately 2 to 2.5 GPM, you can see that the Eccotemp could potentially provide hot water for a kitchen faucet at the same time someone is taking a shower – but not much more than that. This doesn't mean the Eccotemp is inefficient; it's simply designed for lower-usage households.
Ecosmart ECO 27 Electric Tankless Water Heater, 27 KW at 240 Volts with Patented Self Modulating TechnologyThe Ecosmart ECO 27 Electric Tankless Water Heater produces 27 kilowatts of energy, which is equivalent to approximately 92, 000 BTUs. Interestingly, the company quotes two different flow rates for this product, depending on your location. If you're in the northern U.S., where incoming water temperature can be only a couple of degrees above freezing – and therefore quite sluggish – the rate is quoted at 3 GPM. If you're in the south, flow rate is quoted as high as 6 GPM. We give kudos to Ecosmart for this refreshingly honest marketing approach.
Takagi T-KJr2-IN-NG Indoor Tankless Water Heater, Natural GasThe Takagi T-KJr2-IN-NG Gas Tankless Water Heater's energy output is rated at 140, 000 BTUs. Flow rate is quoted at 6.6 GPM. Takagi's product description rates this model as ideal for small homes, yet the company also boasts that this product has the capacity to supply radiant floor heating. Given that the Ecosmart, at 6 GPM, can run several showers simultaneously, it's reasonable to expect that the Takagi can deliver a similar real-world output.
Stiebel Eltron Tempra 24 Plus Electric Tankless Whole House Water Heater, 240 V, 24 kWWhere the Ecosmart provides two different flow rates based on temperature, the Stiebel Eltron Tempra 24 Plus Electric Tankless Water Heater provides two entire charts: one for 240-volt input and the other for 208-volt input. Using the former, this 24 kW (82, 000 BTU) water heater boasts a flow rate of 2.6 GPM at 40°F, rising to a maximum of 5.4 GPM at 75°F. According to the company, the lower output is more than sufficient for a hot shower, while the higher output is suitable for Roman or jacuzzi tubs.
Rheem RTGH-95DVLN 9.5 GPM Indoor Direct Vent Tankless Natural Gas Water Heater
Home Improvement (Rheem)
Rinnai RL94eN Natural Gas Tankless Water Heater, 9.4 Gallons Per Minute - Outdoor
Home Improvement (Rinnai)