Ranein 18kW Electric Tankless Water Heater, 240V On Demand Instant Endless Water Heater with LED Temperature Display, Control Knob, Space Saving Design, Up to 4.3 GPM for Whole House Water
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Availability:
In Stock.
Arrives
Monday, Jun 8
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Color: RE18K, Silver
Features
- Important: This 18 kW, 240 V tankless electric water heater requires 2 dedicated 240 V circuits (2 40 A double-pole breakers and 2 8 AWG cables). Product dimensions: 13.8" 3.1" 18.7". Water connection: 3/4" NPT.
- Powerful Performance: With 99% thermal efficiency and a maximum flow rate of 4.3 GPM, this 18 kW tankless water heater can support 23 household water outlets simultaneously. Enjoy continuous hot water for showers, sinks, or dishwashing without waiting for a storage tank to heat up.
- Save Energy & Space: Unlike traditional tank heaters, this on-demand water heater only heats water when needed, eliminating standby heat loss and helping reduce energy consumption by up to 60%. Its compact wall-mounted design saves valuable space and fits easily in small areas.
- Precise Temperature Control: Easily adjust the temperature from 86F to 131F in 1F increments using the intuitive control knob and LED display. Set your preferred temperature once and enjoy consistent, stable hot water every time.
- Safe & Certified: CSA certified to meet U.S. and Canadian safety standards. Built with leakage protection, overheat protection, drop-tested durability, and a moisture-resistant design. High-quality stainless steel heating elements help reduce scale buildup for longer service life.
- Instant Hot Water Experience: Advanced rapid heating technology provides near-instant hot water, minimizing wait time. Enjoy a comfortable and reliable hot water supply whenever you need it.
Brand: Ranein
Power Source: Electric
Product Dimensions: 13.8"W x 18.7"H
Special Feature: Flame Failure Protection, LED Display, Lightweight, Overheat Protection
Color: RE18K, Silver
Power Source: Electric
Special Features: Flame Failure Protection, LED Display, Lightweight, Overheat Protection
Wattage: 18 KW
Voltage: 240 Volts
Flow Rate: 4.3 Gallons Per Minute
Maximum Temperature: 140 Degrees Fahrenheit
Heat Output: 18 Kilowatts
Mount Type: Wall
Is Electric: Yes
Maximum Pressure: 130 Pound per Square Inch
Item Dimensions W x H: 13.8"W x 18.7"H
Item Weight: 7.9 Kilograms
Material Type: Stainless Steel
Brand Name: Ranein
Model Number: RE18K
Manufacturer: Ranein
Manufacturer Part Number: RE18K
Included Components: Installation Template x1, Parts Kit x1, User Manual x 1, Water Heater x1
Item Type Name: RE18K
Color: RE18K, Silver
Style Name: 18 kW
Frequently asked questions
If you place your order now, the estimated arrival date for this product is:
Monday, Jun 8
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.
To initiate a return, please visit our Returns Center.
View our full returns policy here.
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Bought for our fifth wheel trailer and this performs perfectly.
Reviewed in the United States on May 19, 2026 by Aaron J Carr
Color: RE18K, Silver
I have a small condo and have gone thru 2 water tanks in the last 10 years. When my last one leaked I decided to go tankless. I called my friendly handyman and he recommended this one. I ordered and he installed. I love It!. It was easy to install (per his feedback) and it has so far been an excellent choice. I always have plenty of hot water (just me living here) it has allowed me to control the water temperature and has given me additional space from that ugly cumbersome tank that I had grown to hate. I am saving money on my electric bill (not huge but it all counts) and the cost to install was much less than buying another tank. All in all I highly recommend this unit to anyone that is considering a tankless unit. It is a 5 Star PLUS.
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Reviewed in the United States on August 22, 2024 by SusanB
Color: RE13K, Silver
Bought this unit for a cabin at our lake property, worked great for about a month for doing dishes, after I completed the shower constructions I tried to take a shower and it quite working. Only had the unit 2 months and it quit. Tried calling the support center and sit on hold for a few min and then get a message saying all agents are busy and hangs up. Took the unit back down to see if I could trouble shoot more, still not heating up. Call again and hung up right away. Poor customer support, I would recommend not using this unit. Its been a headache once it quit working.
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Reviewed in the United States on December 23, 2025 by Anthony Cochran
Color: RE18K, Silver
The unit came extremely well packed and protected----nothing funky or weird. It is not very big and looks very simple to install. The actual unit looks really good and is very well constructed, nice materials and finish---also the water inlets and outlets are brass/metal and not plastic ----the temperature etc looks easy and straight forward to operate-----everything on this unit is very clean and assembled well----I only have one issue and its part the manufacturer and maybe in Amazon. This company makes several different models for different uses and water loads----the numbers don't really indicate (at least to me) very clearly that one unit is higher capacity as opposed to lower capacity so it confusing---the Amazon description (to me) makes it not as discernible---it says it, yes, but they make several models and I probably would have gotten the next unit up just to not have issues---I have not installed it yet but am relocating the unit closer to the usage so I am sure not to have issues, failures or lag in hot water----I have confidence because the unit is so well made but still concerned I may come up short. So 4 stars for not having installed it yet and also the lack in clarity in overall models available.
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Reviewed in the United States on July 30, 2025 by David Bro
Well got water heater a few days ago it was replacing an old tank water heater that started leaking. So had to do some replacement of connection a wiring an up grade my breaker, but definitely a lot smaller doesn’t take up any room hardly at all lol. Had to do some reforcement to wall to accommodate the mounting. Seems to work great but not had long enough to really say will update when had time to know more. But think I’m really going to like it. Up dating my previous review now that I’ve had water heater for over a month now will say I definitely glad I bought it love it plenty of hot water for old aching muscles lol works great just hope it holds up as good time will tell on that but well pleased 😀 with it if holds up as well then 5 Stars from me. It is instant hot water but got to remember water that’s in the lines isn’t heated it can’t do that but get there much quicker than old one lol still playing with temperature settings figuring out the best temperature setting did turn down a few degrees lol was getting to hot 🥵 lol but it last I be very happy with it lol do love that doesn’t use any energy when not in use so expecting a little break in my electric bill lol I hope!!!!
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Reviewed in the United States on June 15, 2024 Reviewed in the United States on June 15, 2024 by Randal S.
Color: RE13K, Silver
Effective in producing hot water
Reviewed in the United States on May 6, 2026 by David S Richards
Color: RE18K, Silver
My 18-year-old, 50-gallon water heater failed, and I found this unit on sale. Installing it took me most of the day, including two 30-mile trips to Home Depot for parts. My old heater was in a bedroom closet, leaving little storage space. At my wife’s insistence, I added a water filter to the feed line to catch sediment from our well water. Our two-bedroom, two-bath home led me to choose an 18kW system, which seemed sufficient. After installation, I turned on the water, opened the feed valves, and set the temperature to 120°F, gradually adjusting it to our preference. While I was showering my wife tested the system by running hot water at the kitchen sink. The temperature dipped, but I easily adjusted the faucet to restore heat, similar to our old tank system. I highly recommend this unit. It meets our hot water needs well, and I’m curious to see its impact on next month’s electric bill.
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Reviewed in the United States on August 9, 2025 Reviewed in the United States on August 9, 2025 by TBird
Color: RE18K, Silver
I bought two of these things and one of them started immediately leaking from the top of the interior cylindrical water tank/heater I have tried to repair it with high temperature epoxy, and there’s nothing I can do to get it to stop leaking other than shut the water off to my whole house. I just ordered another one because I’m desperate before I go out of town Can I get a refund on the one that doesn’t work. It was the more recent of the two. The other one works great.
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Reviewed in the United States on March 4, 2026 Reviewed in the United States on March 4, 2026 by J. A.