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Natural Gas Tankless Water Heater - ORBEK 100,000 BTU Up to 4.3 GPM Indoor Installation - CSA Certified On-Demand Instant Hot Water Heater 3/4" NPT Connector Size

  • Based on 182 reviews
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Availability: Only 5 left in stock, order soon!
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Arrives Saturday, Jun 21
Order within 22 hours and 50 minutes
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Style: Indoor Installation


Material Type: 100,000BTU Natural Gas


Features

  • Endless On-Demand Hot Water: The Orbek tankless water heater gas provides up to 4.3 GPM and 100,000 BTU, serving 2-3 fixtures simultaneously for comfortable use throughout your home
  • Safety & Reliable: The Orbek tankless gas water heater is CSA certified and packed with advanced safety features, including dry combustion protection, overheat protection, water leakage protection, flame failure protection, and high water pressure protection etc
  • Energy Efficient: Crafted from high-quality oxygen-free copper, the Orbek heat exchanger delivers superior heat transfer and corrosion resistance. It can adjust between three heating modes to meet seasonal hot water needs, saving energy costs for you
  • Compact Design: With a compact size of 20.5"H x 13.0"L x 7.0"W, gas tankless water heater indoor saves over 50% of space compared to traditional tank water heaters, fitting easily into most corners of your home
  • Stable Temperature Control: The built-in chip adjusts heating power 20,000 times per second, keeping water temperature stable within 1F for a comfortable shower experience
  • LED Digital Display: The Orbek natural gas tankless water heater indoor features a clear screen for sensitive temperature adjustments between 95F and 149F. The power outage memory function ensures you won't have to reset the temperature repeatedly
  • Water Pressure Range: The Orbek tankless water heater natural gas indoor is equipped with low water pressure start technology, allowing it to operate at water pressures ranging from 15 to 150 PSI, even in remote homes far from city centers. Additionally, the operational noise is very low, ensuring it will not disturb your family
  • Easy to Install: Applied with a standard 3- inch OD vent, 3/4" NPT connector size and 120V AC voltage. it's compatible with most homes. Professional installation is recommended for better performance and safety

Brand: Orbek


Product Dimensions: 13"W x 20.5"H


Special Feature: Four Seasons Function, 24/7 Customer Service, 2 & 5 Years Warranty, CSA Certified with Many Protections, Compact Design & Easy Installation See more


Color: White


Wattage: 17 Watt-hours


Brand: ‎Orbek


Product Dimensions: ‎13"W x 20.5"H


Special Feature: ‎Four Seasons Function, 24/7 Customer Service, 2 & 5 Years Warranty, CSA Certified with Many Protections, Compact Design & Easy Installation


Color: ‎White


Wattage: ‎17 Watt-hours


Voltage: ‎120 Volts (AC)


Maximum Flow Rate: ‎4.3 Gallons Per Minute


Maximum Temperature: ‎149 Degrees Fahrenheit


Heat Output: ‎100000 BTU per Hour per Foot per Degree Fahrenheit


Efficiency: ‎[High]


Maximum Pressure: ‎150 Pound per Square Inch


Mounting Type: ‎Wall


Is Electric: ‎No


Style: ‎Indoor Installation


Manufacturer: ‎Orbek


Item Depth: ‎7 inches


Item Weight: ‎25.6 pounds


Country of Origin: ‎China


Item model number: ‎HW100


Special Features: ‎Four Seasons Function, 24/7 Customer Service, 2 & 5 Years Warranty, CSA Certified with Many Protections, Compact Design & Easy Installation


Included Components: ‎Tankless Water Heater x 1 User's Manual x 2 (English and French Version) Quick Installation Poster x 1 Assembly Kit x 1


Batteries Included?: ‎No


Batteries Required?: ‎No


Date First Available: December 22, 2023


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Saturday, Jun 21

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Top Amazon Reviews


  • Better than I expected water heater at a great price.
Style: Indoor Installation Material Type: 100,000BTU Propane Gas
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. ... show more
Reviewed in the United States on April 11, 2025 by Deshi!

  • For the price it's worth it
Style: Indoor Installation Material Type: 100,000BTU Natural Gas
I wanted to come back and leave a review after having it a few months. Installation went fine. Water is hot, but takes a while to get hot to the tap. I will say for our home only 1 thing can use water at a time to get hot water, but you could get warm water on up to 3 things at once. Overall it works for us. If I were to buy again I would get a larger one but this one works and we can manage ... show more
Reviewed in the United States on May 11, 2025 by James

  • Ice cold shower? E8 code: how to make it work
Style: Indoor Installation Material Type: 100,000BTU Propane Gas
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. :) ... show more
Reviewed in the United States on January 23, 2025 by Just make it camo

  • Fairly straightforward install. Heats very fast, easy controls
Style: Indoor Installation Material Type: 80,000 BTU, Propane
I’m excited this is my first tankless water heater. Was fairly straightforward to install. I had it done since I wasn’t the most experienced with plumbing lines. Got a feeling this propane heater is going to work wonders on my electric bill. Something’s I’ve found so far , system heats really fast but takes the lines about a minute to reach my outlet where I’m using the water shower, kitchen sink etc. once it’s there very hot. Did try reducing flow of water in shower and notice if you slow the gpm to much it does indeed shutdown and water gets cold. I’ve taken fairly long showers for me and water stays constantly hot. So far very happy. This will also keep me from having to use my 220 heater and it’s great for my supplemental/ backup solar which supports only 120v. ... show more
Reviewed in the United States on January 24, 2025 by Lee Simmons

  • Great water heater. EXCELLENT Customer Service
Style: Outdoor Installation Material Type: 120,000BTU Propane Gas
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. ... show more
Reviewed in the United States on February 8, 2025 by santa_cruz_man

  • Great value
Style: Indoor Installation Material Type: 100,000BTU Natural Gas
It works great, exactly what it should do, easy to install, and a great price. What's not to love?
Reviewed in the United States on April 19, 2025 by Rob

  • Good solid unit.
Style: Indoor Installation Material Type: 100,000BTU Propane Gas
It is a good solid tankless water heater. IF you look at the picture before you buy, you'll see that the burner set up is superior to most others. I can recommend this unit.
Reviewed in the United States on April 29, 2025 by Mac

  • Perfect
Style: Indoor Installation Material Type: 100,000BTU Natural Gas
Love this was fairly easy to install and works wonderfully
Reviewed in the United States on April 24, 2025 by Candace Carroll

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