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ORBEK Natural Gas Tankless Water Heater - Max 5.1 GPM 120,000 BTU Outdoor Installation - CSA Certified On-Demand Instant hot Water Heater 3/4" NPT Connector Size

  • Based on 234 reviews
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Availability: Only 5 left in stock, order soon!
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Arrives Tuesday, Jun 2
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Color: Pearl White


Features

  • Endless On-Demand Hot WaterThe Orbek tankless water heater gas outdoor delivers 120,000 BTU heating capacity with 5.1 GPM high flow rate, featuring innovative 0.53 GPM low-flow start technology. It can provide a continuous supply of hot water to 2-4 outlets at the same time, making it suitable as a whole-house water heater or a practical gift for friends and family
  • Efficient & Energy-SavingThe highly efficient oxygen-free copper heat exchanger heats water rapidly, while a built-in chip intelligently adjusts the water temperature 20,000 times per second, keeping fluctuations within 1F to provide a stable and comfortable water flow. It also keeps stable combustion even at low flow rates, achieving efficient energy utilization
  • Certified Safety & ReliableThe natural gas tankless water heater is CSA certified, meets stringent North American safety standards, and integrates multiple protections including anti-dry burning, anti-overheating, anti-leakage, anti-flameout, and anti-high water pressure. Whether showering, washing, or using water in the kitchen, you and your family can enjoy a stable supply of hot water with peace of mind
  • Easy Installation & UseThe gas water heater's compact design (15.5"L x 7.3" W x 24.0"H) blends seamlessly into homes, cottages, and apartments. The gas tankless water heater fits standard 3-inch exhaust pipe, 3/4-inch NPT connector, and 120V household power, it's designed for outdoor installation only. We recommend professional installation to help you can enjoy reliable and comfortable hot water instantly
  • Convenient & Worry-freeA 2-year protection on the entire unit and a 5-year protection on the heat exchanger provide you with reliable support. The ttankless water heater is equipped with a smart remote control and LED display, you can easily and precisely set the water temperature between 95F and 149F, and there's no need to reset it after a power outage. Its low-noise operation and energy-saving features create a quiet and worry-free home environment for you

Brand: Orbek


Capacity: 5.1 Gallons


Power Source: Natural Gas


Product Dimensions: 15.51"W x 23.94"H


Special Feature: 2 to 5 Years Warranty, 24/7 Customer Service, CSA Certified with Many Protections, Easy Outdoor Installation with remote controller, Energy Saving & High Efficiency See more


Power Source: Natural Gas


Special Features: 2 to 5 Years Warranty, 24/7 Customer Service, CSA Certified with Many Protections, Easy Outdoor Installation with remote controller, Energy Saving & High Efficiency


Wattage: 42 watts


Voltage: 120 Volts (AC)


Flow Rate: 5.1 Gallons Per Minute


Maximum Temperature: 149 Degrees Fahrenheit


Heat Output: 120000 British Thermal Units


Maximum Pressure: 150 Pound per Square Inch


Mount Type: Wall


Is Electric: No


Smart Home Compatibility: Not Smart Home Compatible


Color: Pearl White


Style Name: Natural Gas


Material Type: Natural Gas


Brand Name: Orbek


Model Number: HS120


Manufacturer: Orbek


Manufacturer Warranty Description: The entire unit is covered by a 2-year warranty, The heat exchanger is covered by a 5-year warranty


Included Components: ‎Tankless water heater x 1 User's manual x 1 (english and french Version) Quick installation poster x 1 Assembly kit x 1


Unit Count: 1.0 Count


Capacity: 5.1 Gallons


Item Dimensions W x H: 15.51"W x 23.94"H


Item Weight: 29.3 Pounds


Item Depth: 15.51 inches


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Tuesday, Jun 2

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


  • Works at or above spec given my setup
Style: Natural gas Material Type: 80,000BTU, 3.6GPM, Indoor
I bought this awhile ago but just installed it. I’ve only got a 1/2” gas line running about 90 feet from the meter @ just under .26 psi and the 80K BTU unit can handle 2 fixtures continuously which is 3.5 gpm. I’m in the yellow zone so it’s working at or slightly above the stated spec which is great. I’ve also got it set to 118 degrees which is above the factory setting of 107. If I try a 3rd fixture it still works but it drops the water temp to accommodate —it doesn’t shut down which is nice. It was easy to install as I had all the connections there and the integrated cord meant I didn’t have to wire a cord to it. Gas is tricky so unless you’ve got all your numbers and calcs done, it’s easy to be disappointed with the performance. All the numbers I quoted above are very important before trying a tankless and the reason I didn’t go with a lager unit. Be aware. So far so good now let’s see if it lasts. ... show more
Reviewed in the United States on September 10, 2025 by Krame

  • Excellent customer service!
Style: Propane Material Type: 120,000BTU, 5.1GPM, Outdoor
I own two of their water heaters, one with electric heat and this one using propane. They were well supplied with parts and any owner supplied parts are easily obtained from Amazon or Lowes/HomeDepot. The propane unit sort of worked but was having issues and soon stopped to ignite at all. I contacted customer service and received a prompt reply. It was quickly determined by them to replace the unit and they sent a shipping label for the return paid by them. They were aware as soon as it was in the UPS system and shipped the new one. Regardless there was an issue, it can happen, it's the best customer service experience. The replacement unit was easily installed in 15-min and for several weeks now its working without issue. The electric unit has had no issues. I'm quite happy with the units and the company. I will note that the names Fogatti and Westinghouse appeared in service communications or on return label. ... show more
Reviewed in the United States on June 27, 2025 by Gary W Gary W

  • Great heater at a great price!
Style: Natural gas Material Type: 100,000BTU, 4.3GPM, Indoor
We've had an on demand water heater installed for years now. This one replaces the last one after it failed during a flood occasion. The new heater is even better than the last at a really good price. Reinstall was simple and the controls are easy to use. If you have a tank hot water heater, try this one! It will save you money on gas and take up much less space. Recommended! ... show more
Reviewed in the United States on August 29, 2025 by Richard Sutton

  • Zero Stars If I Could – Worst Purchase Ever
Style: Natural gas Material Type: 100,000BTU, 4.3GPM, Indoor
This water heater has been a disaster since the day I bought it. It runs for two minutes, then errors out. Every time I need hot water, it’s a fight. Customer service promised, “Don’t worry, we’ll take care of you!” but their “solution” was a video for a different model showing settings that don’t even exist on this unit. When I told them it didn’t apply, their response was to ask me for a video—like the problem is me, not their defective product. Insulting and useless. This heater is garbage, and the support is worse. It’s getting worse by the day, and I’m done wasting time and patience. Save yourself the nightmare—don’t buy this product. ... show more
Reviewed in the United States on September 20, 2025 by Sara

  • On demand water heater
Style: Propane Material Type: 120,000BTU, 5.1GPM, Outdoor
Good heater, need to tape and putty joints to prevent leaking. Otherwise works good for small mobile homes.
Reviewed in the United States on September 27, 2025 by George Mattos Jr

  • good little unit
Needed to replace a 13KW heater that quit after some years of service. Liked this one since it was 14KW and had a 3.6 GPM flow rate. I'm limited to a 60 AMP breaker and this seemed to be the best alternative. Installation was quick and easy. Long hot showers aren't a problem. I had needed a flow restrictor on my tub with the old unit and it took forever to fill. I found that the next larger restrictor works with this unit and tub fills more quickly but a restrictor is still necessary as I would expect it to be with any smaller water heater. Can't speak to longevity yet but so far really like this little heater. My old one only showed the desired water temp. This one shows actual temp which is kind of cool. ... show more
Reviewed in the United States on March 7, 2025 by rich odonnell

  • Orbek on-demand
Style: Natural gas Material Type: 100,000BTU, 4.3GPM, Indoor
Installation was simple. At this early stage, performance is as expected.
Reviewed in the United States on October 4, 2025 by Eric

  • Easy to install, works as it should.
Style: Natural gas Material Type: 100,000BTU, 4.3GPM, Indoor
I bought and installed this one all on my own. Little to no knowledge of plumbing or running gas line, but its so simple and if you follow the instructions, anyone can do it. Highly recommend buying one size up from what you think you need. Ex: if you need it for 3 location, bump up to one that covers 4 or 5. It will give you an extra boost in hot water. ... show more
Reviewed in the United States on June 28, 2025 by Jason Miller

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