Best Under Sink Water Heater Reviews In 2023

Have you faced the bitter experience of cold water when washing anything under the sink? We are sure you are thinking of having a water heater under the sink to relieve you from the worst experience of winter-affected areas.

The under-sink water heater is an efficient electric device. It is energy-saving and designed to provide instant hot water for small usage in the kitchen, garage, and patio, where a larger water heater is difficult to install.

Besides, these heaters are compacted, lightweight, and trendy to fit with your elegant kitchen. This device is essential for the cook, chef and continuously wash and clean at the kitchen, garage, or patio.

We are reviewing on top 8 best under sink water heaters. These are budget-friendly, efficient and reliable. If you don’t want to miss then let’s dive.

Our Top Picks

Durable, environment-friendly, 1440 watts of electric power, fast recovery rate

Elegant design, compatible with the versatile application, automatic temperature control

2.5-gallon capacity, versatile using, fast heating, temperature control

Battery-powered, compacted design, 1440 power wattages, glass-lined construction

It is included all essential components, is corrosion-resistant, and energy-efficient.

8 Best Under Sink Water Heater Reviews in 2023

There have versatile brands for under sink water heaters, but very few are credible for producing quality and affordable products. We have researched numerous items and write this best under sink hot water heater reviews. Our reviewed models are elegant, energy-efficient, affordable, and convenient.

Bosch Electric Mini-Tank Water Heater 2.5 Gallon

Bosch Electric Mini-Tank Water Heater


Bosch is well-known for manufacturing durable, convenient, environmentally safe, and fascinating water heaters. The 2.5-gallon mini tank water heater is no exception, and its simplicity, compact, and sturdy characteristics provide safe and enjoyable water usage.


This Bosch water heater weighs 15.5 pounds. And the measurement of this product is 13.75 x 10.75 x 13.75 inches. It uses 120 volts and 1440 watts of electric power.  

Key Features:

  • It provides 2.5 gallons of hot water per minute and supplies up to 2 sinks of water with a fast recovery rate.
  • It has a 36-37″ cord plug that allows independent installation on the shelf and wall.
  • It reduces power usage and electricity bills with 98% thermal efficiency.
  • The premium quality materials ensure durability and long service. And the simple design enhances the beauty of the existing decor.
What Customers Are Saying:

Since this mini-tank heater stores a couple of gallons of water inside it, we can reduce total water usage. All we need to do is to heat the stored water to have instant access to it. Plus, the easy installation with the plug and two water inlets save physical energy a lot. 

However, the magnesium anode inside of the tank requires frequent inspection and replacement with great hassles.

Camplux ME25 Mini Tank Electric Water Heater 2.5-Gallon

Camplux ME25 Mini Tank Electric Water Heater 2.5-Gallon


The Camplux ME25 2.5 gallon is the best under the sink water heater for its elegant design and high-quality structure. It not only makes heating water handy but also fits well for multiple applications.


This mini-tank water heater measures 11.75 x 10.38 x 17.25 inches and weighs 14.4 pounds. It uses 120 volts and 1440 watts of power and runs on batteries.

Key Features:

  • The thermostat automatically controls water temperature, works against freezing, and the T/P release valve provides overheating protection.
  • With the fast recovery rate, it supplies 2.5 gallons of hot water instantly and two sinks at a time.
  • The built-in insulation foam, glass-lined tank, and high-efficiency heating element ensure durability, long service, easy maintenance, and savings.
  • It is lightweight, conveniently designed, easily mounted and installable on the floor, shelf, or wall.
What Customers Are Saying:

We can use it for motorhomes and fit it under the sink or basin or inside the cabinet. Also, it reduces our worries about getting hot water from distant tanks.

The main problems are, non-professional installation voids the warranty, and no drain valve is included. The included 43.3″ cord plug is a big fat lie, which is only 18″ in reality.

Stiebel Eltron 233219 2.5 Gallon

Stiebel Eltron 233219 2.5 Gallon


In short, Stiebel Eltron 2.5 gallon mini-tank is the best under sink instant water heater under $200. Its sleek and attractive European design seamlessly blends with any decor for industrial, commercial, or residential purposes. 


This product measures 11 x 10.63 x 18.69 inches and weighs 15.9 pounds. It comes with a mounting bracket and factory-installed power cord and plug and runs on batteries. And it uses 110/120 volts and 1300 watts of electric power.

Key Features:

  • The convenient thermostat with a special frost protection setting makes temperature adjustment easier than ever.
  • It can deliver hot water instantly as a stand-alone supplier or inlined with a remote tank.
  • It provides up to 2.5 gallons of hot water using temperatures between 86–140°F within 10 minutes maximum.
  • Compact design and easy and versatile installation save space, power, energy, and water at their best.
What Customers Are Saying:

This German water heater is specially made for those who hate waiting a long time for getting hot water in their shower. Be it an indoor or outdoor sink; it works perfectly in every setting. 

Though it comes with a 6-year warranty, the tank leaks at the 5th year of usage, moreover, the product doesn’t include a drainpipe and requires buying it individually to complete the installation. 

Ecosmart POU 6 Point of Use Electric Tankless Water Heater

Ecosmart POU 3.5 Point of Use Electric Tankless Water Heater


Bosch Electric Mini-Tank Water Heater 4 Gallon

Bosch Electric Mini-Tank Water Heater


If you are looking for a battery-powered mini water tank for the kitchen, you can consider this amazing model from Bosch manufacturing brand. It is super compacted, elegant, and has a 4-gallon larger capacity.


The dimension of the Bosch 4-gallon water tank is 13.75 W x 13.75 H x 13.5 D inches, and the weight is 17.3 Pounds. At the same time, this device has come with a 120-volt outlet and ‎1440 power wattages.

Key Features:

  • It comes with a 2.5-to-4-gallon capacity that can provide hot water within
  • This water heater is designed with a powerful 120-volt outlet plugin and 1440 power watts
  • The premium glass-lined construction material ensures long-lasting service
  • It has come with a corded plug and battery function for easy use and installation
What Customers Are Saying:

 The existing customers have said a lot of positive about this model. First of all, they are happy with the quick hot water supply, long-lasting performance and easy installation. Besides, they are pleased with the fast recovery rate.

However, some customers are disappointed about the price point of this device. And they said that it was quite expensive.

Stiebel Eltron Tankless Water Heater – Tempra 36 Trend

Camplux Tankless Water Heater Electric with LED Display

Camplux Tankless Water Heater Electric with LED Display


Ariston Andris 2.5 Gallon 120-Volt Corded Point of Use Mini-Tank Electric Water Heater

Ariston Andris 2.5 Gallon 120-Volt Corded Point of Use Mini-Tank Electric Water Heater

Specifically, the Ariston Andris 2.5 gallon mini-tank heater is the most suitable for hot water to distant locations. It instantly provides hot water at desired temperatures and does not require a recirculation line.


It measures 14.25 x 14.25 x 10.75 inches and weighs 15.5 pounds, uses 110/120 volts and 1440 watts of power. And it comes with mount brackets, rubber feet, a T/P valve, and a corded plug.

Key Features:

  • The titanium glass-lined tank protects the heater from corrosion. And the CFC-free foam insulation increases energy efficiency.
  • It works both as a primary and secondary source of hot water and instantly delivers 2.5 gallons.
  • It eliminates waiting time, prevents water from getting wasted, reduces bills, and saves space.
  • It comes with a 6-year warranty along with a 2-year warranty for parts.
What Customers Are Saying:

Apart from showering, we can use this convenient mini-tank water heater for washing our face, hands, utensils, wine glasses, etc. The temperature remains constant all the time, and no noise comes from the inside. Even the heated water stays hot inside for a long time.

However, we find the installation process a bit challenging and requires heavy force. Sometimes water leaks and the anode rod needs yearly maintenance to protect the warranty.

The Considering Things Before Buying a Best Under Sink Qater Heater

It is highly important to pick up the right water heater under the sink that has enough efficiency to meet your requirements. Here are some tested factors that can help to choose the best heater for the under the sink.

Heater Size:

An under-sink water heater must be installed in limited space under the sink, so consider the right size. Otherwise, you can’t install it in the exact place. However, you have to ensure how much space you have under the sink. And choose a water heater that will perfectly fit as per the under-sink place.

GPM or Flow Rate:

GPM refers to the water flow per gallon per minute. This measurement is used for the water heater flow rate. We recommend buying a water heater with a higher flow rate. Do note that as higher the flow rate as instant a water heater can provide hot water. For example, a one-gallon flow rate heater can warm one gallon of water per minute. However, you will get more GPM water heaters.


In terms of best under sink tankless hot water heater, it is not essential to think about tank capacity. But tank capacity is a very important factor for a tank included water heater. Good to know that 2.5 – 7 gallons are a standard tank capacity to get continuous hot water. However, you can buy a water heater with a larger or smaller tank according to your water demand.


Voltage is related to the power of an electric device. So, it is crucial to consider the voltage power of your water heater. Make sure about voltage and your electric outlet. The heater will not charge properly if the supplied voltage does not match with the electric outlet.

Recovery Rate:

This rate refers to the amount of water gallon that a water heater can warm. The standard recovery temperature rate is 90-degree Fahrenheit per hour. If the recovery rate is 6.8 gallons, a water heater can heat 6.8-gallon water in one hour.

Heating Power:

Considering the heating power is important because it is the required energy of a water heater to provide hot water. Less heating power is not good for a larger water heater because it can’t provide enough energy. Try to pick up a heater with higher KW heating power. Then you can get more water quickly.

Maintenance and Installation:

The maintenance and installation processes are different based on water heater types, functions and features. You can take a plugin heater for easy installation. However, there are also some heaters with wiring, plumbing and difficult installation process. At the same time, remember to buy a water heater with a user manual.


It is important to compare the water heater price according to the features and functionality that the heater has. You must want to invest in the right place for a worthy product.


Warranty is a great factor for any product. Some manufacturers only offer a warranty for external parts, and some offer a warranty for all internal parts. It is best to choose a water heater with a long warranty.

Benefits of An Under-Sink Water Heater

An under-sink water heater is designed to support additional hot water requirements, and it provides hot water for smaller usage and saves the electricity of a larger heater. This type of heater is compatible with anywhere like rv, boat, cottage and apartment.

Compacted Size:

The under sink warmer is very compacted in size, so it is easier to set up in the small space under the kitchen sink.

Easy To install:

This device comes with a simple installation. So, the user doesn’t need to have depth knowledge of plumbing or electricity.

Fast Heating Time:

Under sink water heater may supply hot water with a fast time. So, it doesn’t use much electricity. Besides, it is highly efficient to reduce your water waste.

Constant Hot Water Supply:

This water heater supplies constant hot water. So, whenever you require water, it can provide instantly.


Under sink water heater need less energy for producing hot water.

What Is An Under Sink Water Heater?

The under-sink water heater is a specially designed electric device for the kitchen. It is powerful to provide instant hot water for dishwashing, hand washing and another small usage. Although this device has come for, you can put it with a wall or mount it on the floor under the sink.

Types of Under Sink Water Heaters

An under sink hot water sink is available in two types, tank and tankless.

Water Heater With The Tank:

Having a tank means a water heater may produce hot water and store it for further use. These heaters can store up to 2.5 – 7-gallon water, convenient for those who want to store hot water. Moreover, a tank included water heater reduces the waste and is easy to set up.

Tankless Water Heater:

When the user doesn’t require hot water, a containerless water heater is the best choice. It can supply hot water instantly and can run till the device is not turned off. This type of heater is convenient for the cookhouse and small space.

How To Take Care of An Under Sink Water Heater

As with any device, an under-sink water heater can be long-lasting with proper maintenance. So, it is essential to check up regularly on all of the problems with your heater, and it also reduces your repair cost.

  • Check up the pressure relief valve to keep the heater safe from overuse
  • Flush out your heater once a year to prevent POU composite
  • Observe the leakage and other faults regularly
  • Check out the thermostats and regulators regularly


  • Are under sink water heaters valuable?

Yes, an under-sink water heater is worthy for kitchen use because it is consistently powerful, efficient, affordable and energy-saving. Besides, it can provide hot water instantly without storing hot water inside the device.

  • How do you get instant hot water under the sink?

Generally, you often need instant hot water in the kitchen in winter, and it is essential to have a recirculation pump that can produce instant hot water. This pump reduces your waiting time for hot water, and it can retain hot water inside the pipe after turning off the heater.

  • What are the best brands for under sink water heater?

Do you know what is the best under sink water heater? although many brands are available in the water heaters, all are not worthy of versatile aspects. Here are some most popular brands that are reliable, affordable and high-quality.

  1. BOSCH
  2. Stiebel Eltron
  4. Ariston
  • Is an instant water heater good for the kitchen?

The instant water heater is good for the kitchen because it is energy-saving as it has no storage system, so there is no chance to waste electricity and hot water.  Most importantly, you may require instant hot water in your kitchen task that a traditional heater can’t provide.

Final Words

Overall, a best under sink water heater is a blessing for a small amount of water requirement in the kitchen and RV. This device is respectively energy efficient, compacted and affordable. We noted our top notch 8 best under sink water heater for your convenience.

We have also mentioned the important buying factors and maintenance tips for you. We hope this guide will help you much when going to buy a water heater for small usage.

Please share your experience with us about this guide. If you have any queries about the under a sink water heater, let us know to update this guide.

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