Looking for the Best Condensing Tankless Water Heater available to buy right now on Amazon but don’t want to have to do all the research on the pros and cons of the different types of Condensing Tankless Water Heater?
Pop Expert have put together this list of the top 10 selling Condensing Tankless Water Heater on Amazon – sorted by overall popularity and positive consumer reviews.
The Pop Expert list of top selling Condensing Tankless Water Heater is the ideal place to start when you are trying to find the Best Condensing Tankless Water Heater for your neeeds.
Popular Condensing Tankless Water Heater on Amazon
Details on the Best Condensing Tankless Water Heater
Bestseller No. 1
Rheem Natural Gas Condensing Tankless Water Heater Indoor Up To 9 GPM, 180,000 BTUs Continuous Super High Efficient Hot Water
- Flow rate of 0.4 - 9 GPM
- Available temperature settings range from 100 to 140F (default setting of 120F)
- Includes electric ignition
- Covered under 1 year labor, 15 year heat exchanger, and 5 year parts manufacturer warranties
- Width 17-11/16-in
Bestseller No. 2
ThermoMate CZ480NG 5.28GPM Condensing Tankless Water Heater, 0.86 UEF High Efficiency Instant On-Demand Hot Water, Residential Indoor Natural Gas Water Heater with Multi-Point Heating
- [Save 15% & Dual Heat Exchanger] - With potential savings of 15% compared to non-condensing units, this condensing tankless water heater delivers outstanding 0.86 UEF efficiency, dramatically reducing energy usage and operational expenses. This performance is made possible by an innovative dual heat exchange system, which combines a corrosion-resistant stainless steel condensing heat exchanger with a highly conductive oxygen-free copper heat exchanger, captures and reuses waste heat that conventional units lose, to maximize heat recovery.
- [5.28 GPM & 114,000BTU] - The ThermoMate instant hot water heater can supply two showers simultaneously, each delivering 105°F water at a flow rate of 2 GPM, based on an inlet water temperature of 65°F. No waiting time, no cold water shocks, perfect for busy households. Adopting advanced water flow sensor, the built-in chip can adjust the heating power 20,000 times per second, ensuring that the hot water within ±1℉ fluctuations for a comfortable shower experience.
- [Safety & Reliable] - This natural gas tankless water heater integrates 8 protections: boil-dry, freeze, flame-out, overheating, over-temperature, pipe blockage, high-temperature lock, and excessive air pressure. Equipped with 4 ceramic heating cores, it auto-activates frost protection when temperatures hit 41°F (5℃). The energy-smart system uses minimal electricity to generate gentle warmth, preventing pipe ice buildup without high energy costs.
- [Smart Diagnostic Display] - Equipped with a 3.5-inch LED touchscreen, it allows you to effortlessly adjust and monitor output water temperature（90°F to 140°F）while providing real-time tracking of water flow, fan operation, and flame status. Advanced error code technology enables rapid diagnosis of water heater malfunctions. The UL-certified 120V/5-foot power cord ensures continuous power supply for real-time monitoring systems.
- [Discharge and Treatment of Condensate Water] - As a condensing unit, this water heater produces mildly acidic condensate water that you will need to discharge into a drain. We recommend installing an economical external condensate neutralizer kit (not included) at the drainage point. This simple add-on neutralizes the acid, protecting your pipes from potential corrosion.
Bestseller No. 3
NEW Rinnai RX199iN Condensing Smart Sense Natural Gas or Propane Tankless Water Heater, Indoor or Outdoor Water Heater, Up to 11.1 GPM, 199,000 BTU
- One Model, Anywhere: This Rinnai tankless water heater is installable indoors or outdoors thanks to our new Versa Vent and powered by either propane or natural gas thanks to a Smart Sense gas control system; RX-OVC vent cap required for outdoor install
- Never Run Out of Hot Water with this Compact Tankless Gas Water Heater: This condensing propane and natural gas tankless water heater from Rinnai is only the size of a small suitcase, but provides up to 11.1 GPM (7 fixtures at once)
- Smart, Efficient Design: This water heater's modern design includes an easy-to-use interface, Quick Flush feature for simplified flushing, as well as a super-high energy efficiency factor of UEF .98; See Controlr module for WiFi control (not included)
- Professional Installation Recommended: Visit the Find a Rinnai PRO page on our website to find a qualified technician to install your tankless water heater, and use the Rinnai Central App for help with setup, service & troubleshooting; We do not recommend installing a water heater without a technician
- Find Your Rinnai: See our product guides, manuals, energy guide, warranty information, videos, and tables to find the right tankless water heater size for your home; Check our Ground Water Temperature Map to see if this heater is optimal for your region
Bestseller No. 4
NEW Rinnai RX130iN Condensing Smart Sense Natural Gas or Propane Tankless Water Heater, Indoor or Outdoor Water Heater, Up to 7.1 GPM, 130,000 BTU
- One Model, Anywhere: This Rinnai tankless water heater is installable indoors or outdoors thanks to our new Versa Vent and powered by either propane or natural gas thanks to a Smart Sense gas control system; RX-OVC vent cap required for outdoor install
- Never Run Out of Hot Water with this Compact Tankless Gas Water Heater: This condensing propane and natural gas tankless water heater from Rinnai is only the size of a small suitcase, but provides up to 7.1 GPM (4 fixtures at once)
- Smart, Efficient Design: This water heater's modern design includes an easy-to-use interface, Quick Flush feature for simplified flushing, as well as a super-high energy efficiency factor of UEF .97; See Controlr module for WiFi control (not included)
- Professional Installation Recommended: Visit the Find a Rinnai PRO page on our website to find a qualified technician to install your tankless water heater, and use the Rinnai Central App for help with setup, service & troubleshooting; We do not recommend installing a water heater without a technician
- Find Your Rinnai: See our product guides, manuals, energy guide, warranty information, videos, and tables to find the right tankless water heater size for your home; Check our Ground Water Temperature Map to see if this heater is optimal for your region
Bestseller No. 5
Rheem RTGH-95DVELN-3 Super High Efficiency Condensing Indoor Tankless Natural Gas Water Heater, 9.5 GPM with WiFi
- Delivers up to 9.5 GPM and 199,900 BTUs, supporting large homes with 3–4 bathrooms for simultaneous showers and appliance use without running out of hot water.
- Energy-efficient condensing design (.93 UEF) saves up to 52% more energy than a standard 50-gallon tank, reducing utility bills while delivering endless hot water.
- Powered by natural gas with 199,900 BTUs, this durable tankless unit ensures fast, reliable hot water—even during peak household demand.
- Flexible venting with PVC runs up to 150 ft (3") and compact design makes installation easier, even in tight spaces—ideal for retrofits.
- Built-in EcoNet Wi-Fi and LeakGuard technology let you monitor, control, and receive alerts from your smartphone for convenience and peace of mind.
Newest Condensing Tankless Water Heater
New
Westinghouse Tankless Water Heater Propane Indoor Installation Max 7.9 GPM 180,000 BTU, WIFI Enable Temp Self Modulating Non Condensing High Efficiency for House or Commercial, APOLO Performance
- 【On-Demand Efficiency】 Westinghouse tankless water heater works only needed, saving energy and costs. Compact yet powerful for whole-home or commercial use. LED display shows temperature, working state and error codes
- 【Smarter Temp Control】 Effortlessly adjust propane tankless water heater via smartphone app or LED panel. The advanced water flow servo maintains water temperature within ±1°F for consistent comfort, eliminating sudden temp fluctuations
- 【High Power】 This tankless water heater propane's 180,000 BTU and up to 7.9 GPM output delivers ample hot water for simultaneous showers and faucets, Can supply water to 3-5 fixtures at the same time
- 【Safety Certified】 This CSA-certified propane water heater indoor delivers worry-free operation with its precision variable-speed fan and freeze protection system. Westinghouse stands behind its durability with strong warranty coverage - 2 years for the full unit plus 5 years for the heat exchange
- 【Easy Installation】 Featuring standard 3/4" NPT connections for seamless integration with most residential plumbing systems, this tankless hot water heater is designed for indoor installation only. Professional assistance is recommended for optimal safety and performance
New
APUS 4 Gallon Electric Mini-Tank Water Heater,Small Under Sink Water Heater for Point of Use, 110V-120V, 1500W Instant Hot Water for RV, Kitchen, Bathroom, Space Save Design
- Fast Heating with Adjustable Temperature：This 4 gallon water heater features a powerful 1500W heating element . With an adjustable thermostat ranging from 86–167°F, this mini tank water heater provides steady, comfortable hot water for washing dishes, cooking, cleaning, and daily use.
- Durable Construction with Multiple Safety Protections：Built with a corrosion-resistant glass-lined or stainless-steel inner tank, this electric hot water tank is designed to prevent rust, leaks, and long-term wear. A built-in temperature & pressure relief valve, dry-fire protection, and overheat shutoff ensure safe and reliable operation at all times.
- Compact Under-Sink Design for Small Spaces：This mini under sink hot water heater fits easily under kitchen or bathroom sinks, inside cabinets, RVs, garages, and tight spaces—ideal for homes, offices, studios, or tiny houses. Compatible with 110–120V, it works as a 120V hot water heater or 110 volt water heater for point-of-use hot water.
- Easy Installation with Flexible Mounting Options：This under sink water heater (120V plug-in design) supports wall-mount, shelf-mount, or floor-mount installations. It features standard 1/2" NPT water connections and includes a complete mounting kit. Use it as a standalone 4 gallon hot water heater or connect it in-line to boost your existing system.
- User-Friendly Operation with Smart Features:LED temperature indicators, a simple knob control, and auto heat-preservation mode make everyday use easy and intuitive. The unit supports both hot and cold water lines, providing a smooth, comfortable experience whether used in the kitchen, bathroom, RV, or utility room.
New
Ranein Tankless Water Heater Outdoor, Up to 1.32 GPM 34,000 BTU, Portable Propane Camping Water Heater with Eco-Mode
- Instant Hot Water for Camping: Unleash 34,000 BTU power for on-demand hot water in seconds! Flows 1.32 GPM at 95°F~149°F (35~65℃) with ultra-low 3.6 PSI start.Perfect for camping showers, pet baths, or RV trips.
- Ultra-Portable Design for Outdoor Use: Weighing just 8.7 lbs, this portable water heater features a foldable handle and hanging chain for tree/RV mounting. Compact size fits backpacks or campers. Setup in under 90 seconds for beach showers or mountain adventures.
- 6-Safety Mode for Reliable Performance: Equipped with auto shut-off at 176°F/80°C, overheat protection, dry-fire shield, and low-flow detection. Freeze-proof drain plug prevents cold-weather damage—ideal for winter camping. Always test gas lines before use.
- No Waiting, Instant Hot Water: Unlike traditional tank heaters, this tankless water heater eliminates 30-minute preheating delays. Get unlimited hot water instantly—perfect for spontaneous outdoor adventures.
- Durable Brass & Weatherproof Build: Crafted with corrosion-resistant brass fittings and a weatherproof housing. Ergonomic dials let you adjust flow/temperature. Built to last for years of rugged outdoor use.
New
ECOTINYMACH Tankless Water Heater Electric 110V, 6000W Instant Water Heater Under Sink, Conversion Between Fahrenheit and Celsius, Remote Control
- Remote Control Convenience: Enjoy unparalleled convenience with the built-in remote control feature. Easily adjust settings from afar, making it perfect for busy households or commercial spaces where accessibility is key.
- Dual Temperature Scales: Switch effortlessly between Fahrenheit and Celsius temperature scales to suit your preferences. This versatile feature allows for precise temperature control, ensuring optimal comfort and efficiency in any environment.
- Compact and Space-Saving Design: Designed for modern living, the ECOTINYMACH 110V tankless water heater takes up minimal space while delivering maximum performance. Its sleek and compact design fits seamlessly into kitchens, bathrooms, or utility rooms without clutter.
- Energy Efficiency and Cost Savings: Save on energy bills with this highly efficient electric tankless water heater. By heating water only when needed, it reduces energy waste and lowers your overall utility costs, making it an eco-friendly and economical choice.
- Installation instructions: Wire requires 8mm ² (8AWG), circuit breaker＞ 60AMP, thread size: 1/2 "NPT, please contact a person with an electrical license to help you complete the wire connection.
On Sale!New
GEN II Ranein Natural Gas Tankless Water Heater Max 8.5 GPM, 190,000 BTU Indoor On Demand Instant Hot Water Heater with LED Temperature Control Panel
- High-Efficiency Endless Hot Water: Boasts max 8.5 GPM flow and 190,000 BTU output, supporting 4–6 taps (shower / kitchen / bar / laundry) for continuous household hot water needs.
- Ranein's Generous Gift: By clicking "Bundles with this item" for purchase, you can get a free vent pipe. (The product itself does not come with an exhaust pipe.)
- Steady Temperature for Daily Comfort: Advanced tech maintains stable water temp, auto-adjusting flow and heat to avoid sudden changes—perfect for showers and daily use.
- Powerful & Safe Bottom Blower: Bottom-mounted blower prevents smoke backflow; auto-adjusts speed for full gas combustion, plus low noise and longer service life.
- Energy-Saving to Lower Bills: Heats water on demand, cutting standby energy waste versus traditional tank heaters—reduces utility costs and supports eco-living.
$699.00
−$69.90
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