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4 Gallon Water Heater Under Sink Instant Hot Water Heaters 1500W 110V 120V Mini Tank,Under Counter Water Heater with T&P Vavle 1/2" NPT for Kitchen,Bathroom,Camper,RV,Grey

  • Based on 181 reviews
Condition: New
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This item's return window has been extended for the holiday season: FREE refund/replacement until Jan 31, 2026

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Availability: Only 10 left in stock, order soon!
Fulfilled by Amazon

Arrives Saturday, Nov 22
Order within 13 minutes
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Color: Gray


Style: 4 Gallon with T&P Valve


Features

  • Rapid Hot Water Supply and Recovery-Kenuos 4 gallon water heater features a 1500W heating power and an upgraded L-shaped 316 stainless steel heating tube, enabling rapid heat conduction with a thermal efficiency of up to 98%. which makes our mini tank water heater can provide hot water in as little as 8 minutes,meeting your demand for a fast water heating solution
  • Customer Friendly 4 Gallon Water Heater-Our under sink water heater comes equipped with a 3-way diverter valve that splits the water flow into two, meeting multi-point water supply needs.It also includes two 24 inch 3/4" ID to 1/2" ID adapter hoses, solving the problem of pipe compatibility with different regional specifications.Additionally,a temperature and pressure relief valve and mounting kit are provided, eliminating the need for you to purchase any extra accessories
  • Safety Design and Exterior Patent-We always prioritize the safety and reliability.Kenuos mini tank water heaters have passed UL,CE,and DOE certifications.Coupled with a seamlessly welded high-strength body,enamel coating,and a temperature and pressure relief valve,making our under sink water heater leak-proof and corrosion-resistant,ensuring the safety of your person and property. and we have applied for exterior patents for all our products,meeting consumers' needs in terms of practicality and novelty
  • Durable Quality And Excellent-The water tank is made of high-quality materials, such as an enamel-coated glass-lined inner tank.It not only effectively prevents water leakage but also boasts excellent thermal insulation performance, reducing heat loss and saving energy.Meanwhile, it has strong corrosion resistance,which can extend the service life of under sink water heater.High-quality insulation materials and design are adopted to reduce heat loss from the hot water in the tank, ensuring that the water temperature is maintained even when the water heater is not in use for a long time
  • Large Capacity,More Uses-This 4 gallon water heater, despite its compact size, offers a relatively large hot water output. It can easily meet the hot water needs of various scenarios, such as providing enough hot water for washing dishes in a small kitchen, cleaning fruits and vegetables, or even for a quick hand - washing session in a bathroom
  • Precaution 1 for This 4 Gallon Water Heater-According to the questions raised by the customer based on the picture,if the pressure relief valve is not tightened and the waterproof Tape is not needed,it may increase the change of water leakage.It is recommended that you install the pressure relief valve and tighten it.If you have any problems or malfunctions,please notify us in a timely manner, and we will provide you with thoughtful after-sales solutions
  • Precaution 2 for This 4 Gallon Water Heater-When your water pressure exceeds 0.75 MPa,it may cause water leakage,which is a normal phenomenon.You need to equip the product with a pressure reducing valve and install it above the cold water outlet.Or replace a 0.9mpa T&P valve
  • Precaution 3 for This 4 Gallon Water Heater-Please fill the water heater with water before turning on the power for the first time. Otherwise, the internal overheat protection function will activate and the water heater will stop working. Do not immediately fill with water at this time. Please disconnect the power and wait for 10 minutes for the stainless steel tank to cool down before refilling with water

Brand: KENUOS


Product Dimensions: 13.5"W x 13.8"H


Special Feature: Dry Combustion Protection, Easy to Install, Overheat Protection, Pressure Release Valve, Waterproof


Color: Gray


Wattage: 1500 watts


Brand: ‎KENUOS


Product Dimensions: ‎13.5"W x 13.8"H


Special Feature: ‎Dry Combustion Protection, Easy to Install, Overheat Protection, Pressure Release Valve, Waterproof


Color: ‎Gray


Wattage: ‎1500 watts


Voltage: ‎120 Volts (AC)


Maximum Flow Rate: ‎0.45 Gallons Per Minute


Maximum Temperature: ‎149 Degrees Fahrenheit


Heat Output: ‎1500 Watts


Efficiency: ‎98%


Maximum Operating Pressure: ‎116 Pound per Square Inch


Mounting Type: ‎Wall


Is Electric: ‎Yes


Manufacturer: ‎KENUOS


Item Depth: ‎13.5 inch


Manufacture Year: ‎2025


Part Number: ‎KENUOS 678


Item Weight: ‎13.52 pounds


Item model number: ‎SY-15


Shape: ‎Square


Installation Method: ‎Floor-Mounted


Special Features: ‎Dry Combustion Protection, Easy to Install, Overheat Protection, Pressure Release Valve, Waterproof


Included Components: ‎24" Length 3/4" ID to 1/2" ID Adapter Hose x 2, 3-way Diverter Valve x 1, 4 Gallon Under Sink Water Heater x 1, Mounting Bracket Kit x 1, Temperature and Pressure Release Valve x 1


Batteries Included?: ‎No


Batteries Required?: ‎No


Date First Available: June 11, 2025


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Saturday, Nov 22

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


  • COMPACT AND EFFECTIVE, BUT WITH A FEW LIMITATIONS
CONVENIENT SIZE FOR UNDER SINK USE The KENUOS 2.5 Gallon Instant Hot Water Heater is designed to fit easily under the sink, and it truly delivers on that front. Its compact size is perfect for small spaces – I installed it in my kitchen, and it fit neatly without taking up much room. For anyone looking to get hot water quickly without needing a full-size heater, this mini tank is a practical solution. QUICK HEATING BUT LIMITED CAPACITY With a 1500W heating element, this water heater gets the water hot pretty quickly. Within minutes, I had piping hot water available, which is impressive for its size. However, with a 2.5-gallon capacity, it’s best suited for smaller tasks, like washing dishes or rinsing produce. For extended hot water use, like filling up a larger sink or running continuously, it may run out of hot water quickly and need a bit of time to reheat. EASY INSTALLATION Installation was straightforward, and the 110V power makes it accessible for most home setups. I had everything up and running in under an hour, and it didn’t require any special tools or additional fittings beyond the basics. This makes it a great choice for a DIY installation if you’re comfortable with some basic plumbing. PERFORMANCE & EFFICIENCY For smaller applications, it performs well, delivering consistent hot water on demand. It maintains a steady temperature, and I didn’t notice any significant fluctuations while using it. However, it’s worth noting that because it’s on the smaller side, the 2.5-gallon tank is limited in terms of sustained hot water supply. VALUE FOR MONEY For the price, the KENUOS Mini Tank Water Heater is a solid choice. It’s budget-friendly, and if you’re looking for a quick, efficient hot water source under the sink, it does the job without breaking the bank. But if you have higher hot water demands, you might find the capacity a bit lacking. FINAL VERDICT Overall, the KENUOS 2.5 Gallon Instant Hot Water Heater is a compact and efficient option for point-of-use hot water in smaller areas. It’s quick, easy to install, and a great solution for small households or light kitchen tasks. Just keep in mind its limited capacity if you need a larger supply of hot water. For the price, it’s a worthwhile investment that performs well within its intended use. ... show more
Reviewed in the United States on November 7, 2024 by Adam Smith

  • Once you go tankless, you never look back!
Color: White Style: 4 Gallon with T&P Valve
I had already ordered one of these for the small bathroom in my husbands shop. It worked out so well, since we don't have access to hot water that far away from the house, that I ordered another unit for a dog wash project on my back patio. Installation is super simple! Literally all you need is an electrical outlet and access to a water outlet in order to use one of these tankless water heater units. You can store one away in a cabinet or leave it out in the open with it's sleek design and quit operating function. The size is perfect and they are super light as I am able to carry this and place it with no issues. It has a dial on the front which allows you to control the water temp on the fly, or you can leave it set to the desired water temp for endless flow of temperature controlled water with no heat fluctuation. What I absolutely love about these tankless water heaters is they end up paying for themselves in the end with the ability to save energy. I can tell you this for a FACT as we have had a whole house system installed for the past 12 years now. Nothing like ENDLESS hot water! We will NEVER have a hot water tank again! ... show more
Reviewed in the United States on March 25, 2025 by The Lions Den

  • Water heater failure after 38 days
Color: White Style: 4 Gallon with T&P Valve
The male pipe connection threads on the water inlet and outlet are not cut properly so you have to over tighten them to keep from leaking. The unit stopped working after 38 days of use. It did not lose water and it had power. There is no contact information for the manufacturer. IT was difficult to relay to Amazon that it should be a warranty issue as it was beyond the 30 days return period. Finally Amazon authorized the return. Unfortunately because of my limited space this was the only unit that would fit so I had to reorder the same water heater. I hope this unit will work for a longer period. If I had a choice I would not buy this water heater. DO NOT PURCHASE IF YOU HAVE SPACE FOR A DIFFERENT UNIT. ... show more
Reviewed in the United States on August 14, 2025 by Virgina B.

  • Decent heater.
Color: White Style: 4 Gallon with T&P Valve
Replaced my existing 2.5 gallon electric heater so already had the correct 1/2 to 1/2 inch water hoses installed. Like other reviews mentioned there is a slight leaking issuse with the pressure valve, the threads seems to be slightly off not allowing a tight connection. I did double up on the pipe tape and it still leaks. However to be fair there is a thick rubber black gasket that would fit tightly into the pressure valve hole. The instructions lack any information so I am going to add it and try again. Update: I installed the thick rubber black o-ring gasket into the pressure valve hoke, pressed down on all sides to make sure it was seated, double wrapped the pressure value threads with plumbing tape and installed. This stopped that leak. As for the water input and output lines, DO NOT USE ANY ADAPTERS ( double or triple the plumbing tape on the treads and connect the hoses directly. As of now there is no leaking. But will check again for the next few days to insure its ok. Other then that the water heats up quickly and unit operates fine. As for the 1 post of that a wire fried and front controls fell off, this heater should not be installed outside on a porch without being inclosed because most of these heaters are not weather resistant which appears to have caused that person's malfunction. ... show more
Reviewed in the United States on September 7, 2025 by wayne paiva wayne paiva

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