We have helped many families evaluate their hot water consumption needs for a decade now. There really isn’t just one BEST on-demand water heater for everyone. Why? It depends on your requirements – installation type (gas or electric) and what water demand you need (high, medium, low).
So, when we are requested to present a top-rated list every year, we use the data from our best-sellers, reliability data and customer feedback to compile our list.
Here are our top-rated tankless water heaters, sorted by capacity of high-demand, medium-demand and low-demand: Here we go:
Our pick of the Best Tankless water heaters:
High Demand: Takagi T-H3-DV-N Condensing High Efficiency Natural Gas Indoor Tankless Water Heater
Model: Takagi T-H3-DV-N Condensing High Efficiency Natural Gas Indoor Tankless Water Heater
Type: On-demand Natural Gas Tankless, for single point-of-use or multiple applications
Flow rate: 10 GPM. It can produce sufficient hot water for a large house, including multiple bath rooms and other appliances
Demand type: High-demand, most suitable for high-occupancy of 3-4 bathrooms household, or commercial application.
Why choose Takagi T-H3-DV-N Natural Gas Tankless Water Heater? Here are the top features and benefits:
- Warrenty: 15-year limited heat exchanger for residential; 5-year limited for commercial use.
- Environmental friendly – Lead free standards.
- Ultra-Low NOx Condensing Technology – minimizes pollution and allows easy, low-temperature venting. The vent design provides flexible and convenient venting with PVC, CPVC or ABS.
- Energy Star® Qualified – one of the most efficient tankless gas water heaters on the market with 0.95 Energy Factor results in substantial cost savings.
- Durability – commercial-grade copper primary heat exchanger and type 316L stainless steel secondary heat exchanger.
- No Pilot Light – IID Electronic Ignition.
- Easy trouble shooting – its temperature controller also displays diagnostic information.
- Easy to link up to 4 Units with no Additional Parts or Accessories Needed. With a multi-unit controller, it can link up to 20 units.
- Internal Freeze Protection System
The Takagi T-H3-DV-N Natural Gas Tankless Water Heater is a super-efficient condensing water heater that supplies large volumes of hot water for high-occupancy residential or commercial application. Easy link-up to 4-20 units, durable and environmental friendly. Excellent warranty: 15-year limited heat exchanger for residential, 5 for commercial. Read our full review.
Medium Demand:Takagi T-H3J-DV-N Natural Gas Indoor Tankless Water Heater
Model: Takagi T-H3J-DV-N Indoor Tankless Water Heater, Natural Gas
Type: On-demand Natural Gas Tankless, for single point-of-use or multiple appliance applications in a moderately sized house.
Flow rate: 6.6 GPM. It can produce enough hot water for two bathrooms at the same time in warmer climates.
Demand type: medium-demand, most suitable for medium-occupancy of two bathrooms household
Why choose Takagi T-H3J-DV-N Natural Gas Tankless Water Heater? Here are the top features and benefits:
- Warranty – 15 years limited on the heat exchanger and a 5 years limited warranty on parts (residential use)
- Environmentally friendly -Energy Factor of 0.82 for Natural Gas (quite high for a non-condensing model)
- Numerous safety features including freeze, overheat, and surge protection.
- Easy maintenance with trouble shooting diagnostic codes.
- Includes both a remote control and power cord as standard features.
- Inlet, outlet thermistors for constant temperature monitoring.
The Takagi T-H3J-DV-N Indoor Tankless Water Heater has great reviews from purchasers. It provides adequate capacity for a moderately sized house and an attractive price with an excellent warranty. Note: This Takagi model requires 4-Inch category III stainless steel venting. It is a non-condensing model with good energy factor of 0.81-0.83 which is lower than condensing heaters. It is a great tankless option for a medium demand residential applications. Excellent warranty. Read our full review.
Low Demand: EcoSmart ECO 11 Electric Tankless Water Heater
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Model: EcoSmart ECO 11 Electric Tankless Water Heater.
Type: On-demand Electric Tankless, for single point-of-use or for small homes.
Flow rate: 2 GPM. It can produce enough hot water for one low-flow shower head and one sink at the same time.
Demand type: low-demand, suitable for one-bathroom application. Or, consider installing this unit near your primary hot water source to as a “water heater booster”
Why choose EcoSmart ECO 11 Electric Tankless Water Heater? Here are the top features and benefits:
- Advanced self-modulating technology – will adjust how much energy needs based on how much hot water is needed.
- Digital temperature control in 1-degree increments.
- Heating elements are durable and are threaded for easy replacement.
- Compact size – saves valuable storage space.
- Lifetime warranty for residential use.
The EcoSmart ECO 11 Electric Tankless Water Heater is a smaller capacity water heater that provides attractive performance at a low price-point for either small home applications or for use in point-of-service applications. This unit can also be used as a “water heater booster”. With its advanced self-modulating sensor technology, it can save up to 60% on the water heating cost. It is suitable for both warmer and colder climates. Lifetime warranty. Read our full review.
Best seller: Rheem RTEX-13 240V Electric Tankless Water Heater
Model: Rheem RTEX-13 240V Electric Tankless Water Heater
Type: On-demand Electric Tankless, for single point-of-use or multiple applications
Flow rate: 3.17 GPM. It can manage two low-flow shower heads the same time, or a standard bath tub.
Demand type: low-demand, most suitable for low-occupancy of 1-2 persons household.
Why choose Rheem RTEX-13 240V Electric Tankless Water Heater? Here are the top features and benefits:
- Compact, modern and clean-line design
- Digital temperature control from 80°F to 140°F (increments of 1°F)
- Easy installation – It comes with a 3-foot electric cable and 1/2 NPT adapters
- Durable with sturdy copper immersion heating elements and brass top
- Energy Star certification – 99.8% energy efficiency.
- Warranty: 5-year limited warranty by Rheem.
- Manufacturer reputation: Excellent. Rheem has been in business since 1925.
The Rheem RTEX-13 is a super popular tankless water heater with purchasers, a best seller for low-demand tankless water heater. And, Rheem is a well-known brand that delivers on its promises for almost 100 years! Read our full review.
Best Value: Ecosmart ECO 27 Electric Tankless Water Heater
Model: Ecosmart ECO 27 Electric Tankless Water Heater
Type: On-demand Electric Tankless water heater, for single point-of-use or mid-sized home applications
Flow rate: 6 GPM. It can manage four low-flow shower heads at the same time, or two standard shower heads and a standard bath tub.
Demand type: medium-demand, most suitable for medium-occupancy of 2-3 bathrooms household.
Why choose Ecosmart ECO 27 Electric Tankless Water Heater? Here are the top features and benefits:
- An impressive flow sensor technology, self-modulating –precisely regulates the energy required to heat up the amount of hot water needed.
- Highest quality copper and stainless components designed for durability, energy efficiency, and easy maintenance.
- Digital temperature control from 80°F to 140°F provides convenient and precise temperature control in 1 degree increments.
- Performance in low temperatures, e.g. delivering 3GPM at 37°F.
- Lifetime limited warranty
- The Ecosmart ECO 27 is well reviewed by purchasers.
The Ecosmart ECO 27 Electric Tankless Water Heater is a great value (as much as 50% savings on the cost of heating water) in terms of performance for a moderate price. It is well reviewed by new purchasers and long-time owners – quality and durability. Read our full review.
Summary: What is the best tankless water heater for you?
The best model is the model that meets your specific needs. So, determine your hot water needs, identify the tankless water heater that has an appropriate flow rate, decide whether gas or electric best matches your needs, and determine which specific product options best match your budget.
Because of their features, reliability, and customer reviews, we recommend the following units to provide endless, instant, on-demand hot water:
If you want additional models for your evaluation, check out our recommended list of :