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
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Availability:
Only 5 left in stock, order soon!
Arrives
Tuesday, Aug 11
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Color: White
Set name: 5.1GPM|Natural Gas|Out
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: 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, Aug 11
This item is non-returnable:
Non-returnable. Transportation of this item is subject to hazardous materials regulation
View our full returns policy here.
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
Color: Snow White
Set name: 4.3GPM|Propane|Ind
So far working great, and one of the best things about it is that it turns on with minimal flow that my prior heaters of this gpm would not operate at. So we no longer need to have faucets at full blast just to get the heater to turn on. Also like that it had 3/4 sized water connections where as other heaters only do 1/2" size which limits flow especially when using plumbing like pex. The only negative is that it does take about a second longer to actually cut on once it detects flow compared to other heaters I have had, just makes it a bit longer to wait for hot water to start coming out. Otherwise, seems like a high quality heater, hopefully it will last without throwing error codes like I have had with these style heaters in the past. Keep in mind, these style of water heater do not need to mix with cold water like a traditional heater. You want to set the temperature to the hottest setting that you need out of the tap without mixing with cold water. then use the cold water to adjust down as needed. You do NOT need to set it to some high temp to then mix with cold water like you normally do with a tank in order to not run out of cold water in the shower. these are on demand so you will never run out. I see alot of reviews saying it cuts off when they mix it with cold water. likely they are having the temp up too high and mixing too much cold water with it causing the flow to drop down too much and causing it to cut off. this will happen with ANY of these tankless style water heaters. Especially in an RV where flow is often lower to begin with.
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Reviewed in the United States on April 11, 2025 by Deshi!
Color: White
Set name: 5.1GPM|Propane|Out
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.
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Reviewed in the United States on June 27, 2025 Reviewed in the United States on June 27, 2025 by Gary W
Color: Snow White
Set name: 4.3GPM|Propane|Ind
E8 code left cold showers increasing in frequency. Exhaust temperature increasing over time. Finally dropped to 30 seconds of hot water at a time. 2 months of use before it was thrown away. Last Japanese made hot water heater lasted 20 years. Unit works well after you program it. Installed correctly with 3" vent pipe you may see "E8" code displayed when you jump out of your ice cold shower. This is the Fan speed exceeding programmed maximum of '74' (no units displayed). 1. turn display off with power button, 2. unplug, 3. re-plug and after 2-3 seconds press the down arrow, 3. PP should appear on display, 4. press power button you will be in the programing parrameter list- use up arrow to navigate to Hc= fan speed, select by pressing power button, increase from 74 to 95 (max is 99), press the power button to exit to main menu, use up arrow to find QU (looks a lot like 9U because of poor pixelation). press power button to select, This saves the setting changes. press power again if you aren't back to the general temperature display. Now your shower will stay warm. :)
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Reviewed in the United States on January 23, 2025 by Just make it camo
Home is 3500+sq ft, built in 1960. Previous water heater was typical 40 gallon gas. PROS --easy installation process (husband set up, but I supervised), small, compact and wall mountable for tight spaces, works well --when it turns on, heater makes a light clicking sound, followed by a low rumbling hum that continues until hot water tunes off. (So you know it's working) -continuous hot water supply, water heater quality is great- feels very hot at 125 CONS -Cannot use more than one appliance at time(washing machine/shower/dishwasher) bc the water pressure and temperature will go in and out (would need a water heater with a higher btu) -cost was a bit steep but it is continuous hot water supply so I suppose one could justify it like that. OVERALL I'm pretty satisfied with the purchase. As the replacement of an ancient appliance, the (+)s for this product def outweigh the (-) which there weren't many. We bought this as sort of test to see what it could do or if it was worth it to splurge for the more costly product. But in the end, we ended not upgrading bc we didn't have to.
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Reviewed in the United States on November 13, 2025 by Denise
Color: White
Set name: 5.1GPM|Propane|Out
I’ve been on Amazon since 1998 and this is the best 3rd party seller I have ever encountered. After buying the water heater there was an issue with the igniter. I emailed this seller and got an immediate response on what to test and how to test it. If it failed they said send it back and we will swap asap. I did not have to buy their water heater again when I return this one. I chose to buy it because prior to purchasing the first one. I did some research and it seemed to be a very good in-line water heater for that price range. I felt good about my purchase. When there was a minor issue, I was not deterred so I thought I would purchase it again. Throughout the way, they remain in constant contact with me even when I didn’t. This water heater was installed in a home and while I was returning it, there was no hot water. I emailed them my situation and they received the water heater at 10 AM on a Tuesday. They credited my account by 11 AM that same day. I ordered the replacement that same day, and they shipped the replacement all in the same day. The new unit arrived two days later. I installed it and it has been operating now flawlessly for over a month. It’s a very good machine. I highly recommend this water heater and the seller. They really stand behind their product and their communication skills are excellent.
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Reviewed in the United States on February 8, 2025 by santa_cruz_man
Color: White
Set name: 3.6GPM|Natural Gas|Ind
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.
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Reviewed in the United States on September 10, 2025 by Krame
This works great and we never run out of hot water. We are a family of five.
Reviewed in the United States on March 31, 2026 by Lindsey Ann
Color: White
Set name: 5.1GPM|Propane|Out
Leaking electronic servo in lower right corner above cold water inlet pipe. I like the fact it is an outdoor unit so that water drips onto landscaping. However water leaks are bad using excessive well water. I do not know how to repair or replace leaking valve. Ii like this product very much except for leaking valve ((see photos attached)
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Reviewed in the United States on February 13, 2026 Reviewed in the United States on February 13, 2026 by Harry Dawson