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Westinghouse

Westinghouse Natural Gas Tankless Water Heater Indoor Installation Max 5.1 GPM 120,000 BTU, WIFI Enable Temp Self Modulating Non Condensing High Efficiency for House or Commercial, APOLO Performance

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Availability: In Stock.
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Arrives Saturday, Dec 13
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Material Type: 5.1 GPM, Indoor Installation


Style: Natural Gas


Features

  • 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 tankless water heater gas via smartphone app or LED panel. The advanced water flow servo maintains water temperature within 1F for consistent comfort, eliminating sudden temp fluctuations
  • High Power This natural gas tankless water heater's 120,000 BTU and up to 5.1 GPM output delivers ample hot water for simultaneous showers and faucets, Can supply water to 2-4 fixtures at the same time
  • Safety Certified This CSA-certified gas tankless 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 water heater natural gas whole house is designed for indoor installation only. Professional assistance is recommended for optimal safety and performance
  • Usage Reminder Ensure the unit is connected to a 120V AC power source. In temperatures below 5F or during extended periods of non-use, fully drain the system to prevent potential damage

Brand: Westinghouse


Product Dimensions: 12.5"W x 23.9"H


Special Feature: 2-5 Years After-Sale Support, CSA-Certificated, Easy to Install, WIFI&APP Control, ±1℉ Temp Control See more


Color: Gray


Wattage: 42 Watt-hours


Brand: ‎Westinghouse


Product Dimensions: ‎12.5"W x 23.9"H


Special Feature: ‎2-5 Years After-Sale Support, CSA-Certificated, Easy to Install, WIFI&APP Control, ±1℉ Temp Control


Color: ‎Gray


Wattage: ‎42 Watt-hours


Voltage: ‎120 Volts (AC)


Maximum Flow Rate: ‎5.1 Gallons Per Minute


Heat Output: ‎120000 BTU per Hour per Foot per Degree Fahrenheit


Efficiency: ‎High Efficiency


Maximum Operating Pressure: ‎150 Pound per Square Inch


Mounting Type: ‎Wall


Is Electric: ‎No


Manufacturer: ‎Westinghouse


UPC: ‎850057631982


Manufacture Year: ‎2025


Part Number: ‎HW120A1G-NG


Item Weight: ‎30.6 pounds


Item model number: ‎HW120A1G-NG


Size: ‎APOLO-120K


Finish: ‎Coated


Pattern: ‎Indoor Installation


Installation Method: ‎Wall-Mounted


Type of Bulb: ‎LED


Special Features: ‎2-5 Years After-Sale Support, CSA-Certificated, Easy to Install, WIFI&APP Control, ±1℉ Temp Control


Included Components: ‎Tankless Water Heater x 1, User Manual x 1


Batteries Included?: ‎No


Batteries Required?: ‎No


Date First Available: June 15, 2025


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Saturday, Dec 13

This item is non-returnable:

Non-returnable. Transportation of this item is subject to hazardous materials regulation

View our full returns policy here.

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Top Amazon Reviews

    • Poor shipping choice USPS is awful
Material Type: 8.1 GPM, Outdoor Installation Style: Natural Gas
Try to avoid usps shipping obviously dropped as box was heavily damaged and left in open wet from rain . Luckily product looks ok ? USPS IS ALWAYS A PROBLEM . Avoid USPS
Reviewed in the United States on October 2, 2025 by Robert lockward
    • Solid performance, stable temperature, easy setup with app control
This tankless water heater from Westinghouse works consistently in our indoor setup. The temperature remains stable, and the digital control panel makes it simple to monitor. Connecting to the Wi-Fi and using the app was straightforward — it allows for quick adjustments without walking over to the unit. The unit's compact size fits well in the space we had planned. It operates quietly and the materials look durable. The install process followed the included instructions, and everything aligned as expected. We didn’t experience any error codes or operational problems. The display is responsive and the design is clean and modern. ... show more
Reviewed in the United States on December 5, 2025 by Amazon Customer
    • Got my basement closet back!
Review Image by Joyce Yien Joyce Yien
Review Image by Joyce Yien Joyce Yien
Review Image by Joyce Yien Joyce Yien
The media could not be loaded. Getting rid of that massive, rusty old tank heater freed up so much space! This little box living on the outside of my house is magic. The installation was clean, and now I have a whole new storage area where the tank used to be. If you're tight on space indoors, outdoor tankless is the only way to go We put this tankless in last week replacing the old tank heater. I can tell you it was an unbelievable pleasing upgrade to free up so much space! Installation was straightforward for my plumber, and the unit’s compact size freed up a ton of space in the utility area, and now I have a whole new storage area where the tank used to be. It's much lighter and smaller than my old tank, and I love that it doesn’t sit there heating water all day long. This little box living on the outside of my house is magic. If you're tight on space indoors, outdoor tankless is the only way to go. ... show more
Reviewed in the United States on December 5, 2025 by Joyce Yien Joyce Yien
    • Nailed all the specs I cared about
I spent weeks comparing BTU, GPM, and warranty. This Westinghouse hit the sweet spot. 120k BTU is plenty for our size home, the 5-year heat exchanger warranty is solid, and it's CSA certified. Some other brands skimped on those details. It performs exactly as the specs promised. Do your homework and you'll see this one is a top contender. ... show more
Reviewed in the United States on December 4, 2025 by Jeff Bezos
    • Going strong
There's not much to say but it works. My uncle was doing a new home and was installing natural gas lines, so he needed a new water heater. This was available with 2 day delivery, 5 days faster than the local home improvement stores. Westinghouse is also a reputable brand, so there weren't any concerns about quality. Ordered on a Tuesday, delivered and installed on a Thursday with hot water that night. We did have one question, but a quick call to the included support line got us taken care of in less than 15 minutes. I can say that, as of now, if we need another natural gas water heater, this company is the first I'm looking toward. ... show more
Reviewed in the United States on November 17, 2025 by darthmasterbane
    • No More Shutdowns in Windy Chicago
Material Type: 5.1 GPM, Indoor Installation Style: Natural Gas
The media could not be loaded. My 20th-floor Chicago apartment used to have heater shutdowns weekly due to strong winds. This water heater’s 12-level wind resistance actually works – the DC fan adjusts speed based on real-time wind pressure. Installed it myself in 90 minutes thanks to the clear manual. Buy it, please! ... show more
Reviewed in the United States on June 27, 2025 by Tehya LaMere

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