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APUS

APUS 18kW Tankless Water Heater Electric, 240V Instant On Demand Hot Water Heater, Up to 4.4 GPM with LED Display, Space-Saving and Energy-Saving Whole House Water Heater Design

  • Based on 108 reviews
Condition: New
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Availability: In Stock.
Fulfilled by Amazon
Arrives Saturday, Aug 1
Order within 18 hours and 29 minutes
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Set name: AP-18kW(NEW),Knob


Features

  • Enjoy continuous hot water whenever you need it. The whole-house models 18kW tankless water heater electric delivers up to 4.4 GPM for 23 uses at once, such as showers, sinks, or laundry. No preheating, no waiting, and no temperature drops
  • This electric water heater ultra-slim wall-mounted heater (13.7" 11.42" 3.54") saves up to 90% more space compared to traditional tanks, freeing up valuable space in your home. With 3/4" NPT connections and 240 V compatibility(requires 240 A breakers, 2 set of 8 AWG cable), installation is easy and flexibleideal for whole-house or point-of-use setups in bathrooms, kitchens, or laundry rooms
  • Achieving 99.8% thermal efficiency, this electric tankless water heater on-demand water heater heats only when water flowscutting up to 60% on energy bills. Zero standby heat loss and an anti-scale interior extend lifespan and maintain strong performance for eco-conscious households
  • Adjust your preferred temperature between 86F131F using the LED digital display with 1F accuracy. The electric hot water heater built-in memory keeps your settings even after power outages. Self-modulating technology optimizes power usage based on flow rate, ensuring stable temperature and lower energy waste
  • Engineered with 6-layer protection, including anti-leakage, overheat, and surge safeguards. The separated water-electricity design prevents corrosion and ensures long-term reliability

Description

NEW 18kW Water Heater 14kW Water Heater 18kW Water Heater 27kW Water Heater 4.5kW Water Heater

Brand: APUS


Power Source: Breaker：2 x 40 AMP，Cable Required：2 set of 8 AWG， Hard Wiring Required


Product Dimensions: 11.42"W x 13.7"H


Special Feature: 24/7 Customer Service and Warranty, Demand Hot Water, High Efficiency, Separation of Water and Electricity, ±1°F Stable Temperature Control See more


Color: Gray


Power Source: Breaker：2 x 40 AMP，Cable Required：2 set of 8 AWG， Hard Wiring Required


Special Features: 24/7 Customer Service and Warranty, Demand Hot Water, High Efficiency, Separation of Water and Electricity, ±1°F Stable Temperature Control


Wattage: 18000 watts


Voltage: 240 Volts


Maximum Temperature: 131 Degrees Fahrenheit


Heat Output: 18000 Watts


Efficiency: 99%


Mount Type: Wall


Is Electric: Yes


Item Dimensions W x H: 11.42"W x 13.7"H


Item Weight: 15.21 Pounds


Item Depth: 3.54 inches


Brand Name: APUS


Model Number: AP-ADSK180-H18


Unit Count: 1.0 Count


Manufacturer: APUS


Included Components: Instant electric water heater x1; Instruction manual x1; Rubber x5; screw x5; Installation guide card x1; sealing ring x2


Color: Gray


Style Name: AP-18kW


Material Type: Sheet Metal with Insulating Paint


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Saturday, Aug 1

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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Leasing options through Acima may also be available during checkout.

Learn more about financing & leasing here.

Similar Products

Top Amazon Reviews

    • Professional quality and excellent value.
Set name: AP-27kW,LED Touch
Review Image by Rong
Bought this for a client's home. It’s a powerful 27kW unit that delivers consistent hot water. Much more affordable than big-box store brands but works just as well. The digital display is user-friendly and the gray finish looks premium. Great choice for any home renovation.
Reviewed in the United States on May 1, 2026 by Rong
    • Under sink water heater
Instant hot water at our sink that used to take at least 5-10 minutes to warm at all
Reviewed in the United States on June 25, 2026 by Dawna
    • Love it
Set name: AP-18kW,LED Touch
Easy install, doesn't heat as fast as my previous unit but does the job and once it's hot it's hot and stays hot.
Reviewed in the United States on May 27, 2026 by ant
    • Temp range misleading
Set name: AP-18kW,LED Touch
Unit will not reach 140°@4gpm unless in coming water is already at 90° per customer support. Other then that it's a good unit. So if you own a garden tub and want to keep your wife happy don't but this one
Reviewed in the United States on April 12, 2026 by wesley chappell
    • Nice choice!
So far so good, works excellent, you'll need fittings from your local supplier and make sure you tighten them well to prevent any leaks. Be careful with your heat setting as this thing will heat water to a scalding temperature!
Reviewed in the United States on April 17, 2026 by Fast Eddie
    • Lots of hot water
Set name: AP-18kW,LED Touch
Great value. Upgraded from 13kw heater. Required 1 more wire.
Reviewed in the United States on June 14, 2026 by RM.
    • Water Heater
Set name: AP-27kW,LED Touch
I haven't installed it yet but looks like it will do the job for what I need. A friend bought the same one & absolutely loves it so I'm hoping for the same results.
Reviewed in the United States on May 22, 2026 by Alan Hart
    • Great product and super customer service
After an error of installation on my part, caused the unit to not work. Customer service sent me a replacement free of charge even though it was my fault. Installed the replacement correctly and it worked perfectly. This company stood behind their product. Super customer service. I would highly recommend them. ... show more
Reviewed in the United States on March 24, 2026 by j9wern

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