Small Water Heater: Reviews and Buyer Guide

Small Water Heater

A small water heater can help provide hot water to even the most difficult places. Whether you need hot water in a bathroom that's not well served by your main water heater or you need a stand alone unit to service a shop, garage or other outbuilding, a small storage tank water heater can do the job.

Frequently called point-of-use or utility water heaters, they typically range in size from 2.5 to 19 gallons. In this article we'll provide you with a buyers guide and individual reviews to help you determine the right unit for the job.

How to Buy a Small Water Heater

Since small storage tank water heaters come in a variety of sizes, it's important to know how to properly select a unit that will be able to deliver the proper amount of hot water necessary.

For the most part, the same rules apply in sizing a small water heater as you would use to select a water heater that'll service your home. Simply focus on the specific area you want to provide with hot water, such as a bathroom. 

There are 2 important factors to consider when sizing a tank-style water heater:

  • Tank Capacity: The tank capacity is simply how much water the tank is designed to hold. Obviously, a water heater that has a large tank will be capable of delivering more hot water than a unit with a small tank.
  • Recovery Rate: The recovery rate is the amount of time required to reheat the water within the tank. The main factor is the efficiency and wattage of the water heater's heating elements. A heating element with a high wattage should be able to heat hot water faster, and therefore the unit should have a shorter recovery rate.

Consider Your Needs

One of the most important steps in determining the correct size water heater for your project is to have a good understanding about the amount of hot water you'll be needing at the location. If you'll only be using the unit to heat water for a hand sink, a 2.5 gallon tank will most likely meet your needs. However, if your new small water heater will be servicing a dishwasher, shower or other higher demand output, you'll need a larger sized tank. 

Since a tank-style water heater can only deliver the amount of hot water that's stored within the tank, we highly recommend overestimating your needs. Once the tank has depleted it's hot water supply you'll be left with cold water until the unit recovers (heats more hot water).

There is a way to get around the fear of depleting your hot water capacity. Most point-of-use water heaters can be used to boost your home's main water heater. By installing the unit in-line with your main system, the smaller tank will deliver hot water until your main tank can take over. Thus, eliminating the wait time as the hot water flows thru your home's plumbing.

How a Tank-Style Small Water Heater Tank Works

Advantages of a Small Water Heater

There are many advantages to installing a small water heater in your home. Although many are used as standalone units, it's also very common to use them to boost your home's main water heating system at the point-of-use. Here are a few of the advantages:

  • Water Temperature - When a water heater is installed closer to the faucet the hot water can arrive nearly instantly. Saving you time (waiting for hot water) and money (lower utility bills).
  • Water Pressure - The water pressure will increase immediately since the point-of-use unit is installed near the faucet. If you own an older home, this can be especially helpful.
  • Less Waste - If reducing your carbon footprint is important to you, a point-of-use water heater can make a big impact on reducing the amount of wasted water while you're waiting for hot water to run thru your home's water lines.

Small Water Heater Reviews

Stiebel Eltron has been building high quality water heaters for over 90 years. These small water heaters can easily deliver hot water for hand washing and kitchen applications.

No special wiring is necessary. Simply fill the tank with water and plug it into a standard 120-volt outlet. There are several options available for installation:

  1. Stand alone water heater.
  2. In-line with your main hot water heating system.
  3. Domestic Hot Water recirculation loop to buffer temperatures.

Just the Facts

Dimensions: 26.5 x 16 x 16"

  • 4-gallon Tank
  • 120-volts, plugs into a standard outlet
  • 1200-watts
  • Glass lined tank
  • Wall mount bracket included
  • 6-year tank warranty
  • 2.5-gallon and 6-gallon tank sizes available
Our Rating: 5 out of 5

Reliance Water Heater Company knows a thing or two about manufacturing water heaters. They back up their products with a solid 6-year warranty and deliver a unit that deserves to be on your short list.

The compact series is designed to fit into tight spaces. The water inlet and outlet connections are installed on the side, yet can be switched to the top if necessary.

Whether you want to hide this unit in a crawl space, under a cupboard or mount it on a shelf, it should fit nearly everywhere. 

Just the Facts

Dimensions: 15.2 x 14.1 x 14.1"

  • 6-gallon Tank
  • 120-volts, plugs into a standard outlet
  • 1650-watt element
  • Glass lined tank
  • 6-year tank warranty
  • 10-gallon tank size available
Our Rating: 4.5 out of 5

The Bosch ES4 Tronic 3000 can easily fit under your sink and function as a standalone unit or it can be installed in-line with your home's main water heating system.

The unit comes with a 36" power cord and plugs into a standard 120-volt outlet. The external dial, located on the front of the unit, will make temperature adjustments easy. This point-of-use small water heater is not only a strong performer, but it also has a sharp, sleek look.

Just the Facts

Dimensions: 13.75w x 13.75h x 13.5d

  • 4-gallon Tank 
  • 120-volts, plugs into a standard outlet
  • Glass lined tank
  • Wall mount optional
  • 6-year tank warranty
  • 2.5-gallon and 7-gallon tank sizes available
Our Rating: 4.5 out of 5

Rheem is a big player in the hot water heating industry. They build high-quality, no-nonsense units that are backed with a solid 6-year warranty.

 The Rheem Professional Classic series offers a wide range of tank sizes. The 20-gallon unit is a great fit for spaces where your demand for hot water is high, such as a bathroom. 

However, keep in mind, this is still a small hot water heater, and if you don't properly size your hot water demand, you may be left with cold water. If you're looking for a work horse of a water heater, Rheem should be on your short list. 

Just the Facts

Dimensions: 15" x 15" x 30"

  • 20-gallon Tank 
  • 120-volts, plugs into a standard outlet
  • Rheemglas lined tank
  • 6-year tank warranty
  • 2-gallon and 6-gallon tank sizes available
Our Rating: 4.3 out of 5

EcoSmart water heaters are rapidly gaining in popularity. As a relatively new company, they focus on building quality products for a fair price. 

Their Mini-tank series is a great fit for people looking for point-of-use water heaters, whether it be for a home, RV or even a boat.

With 4 units to choose between, ranging in size from 1-gallon to the larger 6-gallon tank, you should be able to find a unit that meets your needs. All plug into a standard 120-volt outlet, with the exception of the 6-gallon unit, which will need to be hardwired. 

Just the Facts

Dimensions: 20" x 13.8" x 14.5"

  • 6-gallon Tank 
  • Must be hardwired (6-gallon tank only) 
  • Wall mountable
  • 5-year warranty
  • 2.5-gallon and 4-gallon tank sizes available
Our Rating: 3.9 out of 5

The Eccotemp Mini Tank series offer 3 different tank sizes to choose between, and the glass-lined welded steel tank is designed to help prevent corrosion.

Mount the unit on the wall or position it on the floor, whichever works for you. The LED lights on the front will keep you informed when the tank is heating, and the temperature dial will make adjustments a snap.

Just the Facts

Dimensions: 14.5" x 11.8" x 10.4"

  • 2.5-gallon Tank 
  • 120-volts, plugs into a standard outlet
  • Wall mount optional (bracket included)
  • 5-year warranty
  • 4-gallon and 7-gallon tank sizes available
Our Rating: 3.5 out of 5