Top 10 19-Gallon Water Heaters for Compact Spaces

Water heating eats up more than 20% of most household energy budgets. That’s a bigger chunk than most people realize. Choosing the right 19 gallon water heater can make a real dent in that number.

The decision usually comes down to gas versus electric, and lately more people are going electric for the easier installation and lower upfront cost. With so many similar-looking products on the market, though, figuring out which one actually delivers can be tricky.

Quick Comparison Chart

1. Ecosmart POU 3.5 — Best Overall

The Ecosmart POU 3.5 electric tankless water heater has a specific modification for under the sink and a flow rate of 0.5 GPM. The heating temperature adjusts according to the water flow rate.

It’s tankless and small in size, which allows under the sink installation. The smallest Ecosmart size doesn’t allow more than a sink or an inlet flow of water with temperatures below 57 degrees Fahrenheit.

The heater is ideal for wet bars, doctor’s offices, strip malls, boats, bathroom sinks, and recreational vehicles. Verify to make sure the heater suits your electrical requirements and your demand before purchasing.

When using the heater, remember to slow down the water flow if it comes with a lower temperature than you expect.

2. American Standard CE-20-AS — Best Point-of-Use

The American Standard 19-gallon water heater is the best solution for situations where it’s not practical to run long water pipes. You can install the heater in spaces under the cabinet, mop sink, counters among other confined regions.

The heating appliance comes with a 6-year warranty for the tank and a year warranty for the parts. The water heater tank comes with an installed brass valve for pressure and temperature relief.

The point of use water heater has a 150 PSI working pressure and 300 PSI test pressure with a 100 percent hydraulically factory test. It has a dimension of 18.5 x 18.5 x 24.88 inches and a 73.6-pound weight.

The heater tank is a gauge steel tank with a dura glass lining that withstands 1600 degrees Fahrenheit and optimum protection against corrosion.

3. Bosch Tronic 3000 — Best Mini-Tank

Looking for a convenient water heater that fits under your sink and provides hot water right to where you want? Bosch Thermo technology water heater is an efficient water heater with premium glass-lined material for longer service life.

The 37-inch cord plugs into a 120 volts outlet allowing independent installation or in the same line with a significant water source. It supplies two sinks simultaneously and with a fast recovery rate, eliminating the long waits for hot water at the sink.

The point of use water heater comes in three compact sizes: floor-mounted or wall hung. The water heater is small and lightweight, which occupies space on your shelf, wall mount, or floor.

The sleek aesthetic color and its design is attractive for blending with the decor.

The external dial enables you to control the temperature range while the temperature and pressure valves take care of your safety. The tank has a thick CFC-free foam material for insulation and maximum energy efficiency, including the glass-lined tank for improving durability.

4. Rinnai V65iN — Best Tankless

The Rinnai V65iN is a high-efficiency tankless warm water heater that uses natural gas and is only suitable for indoor installation. It has a 6.5 GPM hot water flow rate, which varies with the temperature of the ground.

It comes with a Control-R 2.0 mobile application timer that allows remotely tracking of the temperature. You don’t need to continue scheduling your hot water supply, and with the Rinnai heater, you’ll never run out of hot water.

The ThermaCir360 technology recirculates the hot water in pipes allowing you to get a steady supply. Unlike other heaters, you won’t wait for hot water to travel from a tank to your shower.

The compact design saves your space by allowing installation in non-traditional areas such as crawl spaces, attics, or closets. It consumes 40% less than conventional tanks because you only heat water when you’re in need.

The tankless heater is sustainable and reliable. Each part is replaceable, so you don’t need to buy the whole system in case of a single section malfunction.

5. Camplux ME25 — Best Compact

The Camplux lets users have a happy lifestyle as they get a real service that guarantees value for their money. Camplux is a 2.5-gallon point of use small tank that can fit under your sink and provide hot water to the points you need.

It has an approximate weight of 20 lbs. The heater tank is perfect for patio kitchen stations, garages, basement wet bars, attics, on a boat, or RV to check that hot water is quickly on your hand.

It’s easy to maintain with a glass-lined interior that makes it more durable. The heater has a thermostat fitting for temperature regulation, including a limit device that protects against overheating.

The red indicator lamp lights up when heating water.

The fast recovery makes sure a steady supply of hot water, eliminating long waiting times. You can connect the heater in line with a hot water line or plug it directly to a 120 Volts outlet for independent connection.

It’s easy to install, and you can do a floor mount or shelf wall for easy tapping into the cold water line. The CSA-listed temperature and pressure relief valve provides safety.

6. ATMOR AT-EJSH-5 — Best Shower

Are you looking for a different and unique water heater for your shower? This 6kW/240V electric tankless water heater provides an endless hot water supply in your showers.

The tankless water heater is ideal for showers and areas with a tropical climate.

The heater comes with a handheld shower, hose, a soap dish, and a rise rail. You’ll enjoy a hot water shower when you want without delays.

It’s easy to install the compact design, which already has a connecting wire for electrification.

Once you install the heater successfully, it’s ready to release hot water within a few seconds. It requires a 30-amp double pole breaker.

The product weighs just 4.41 pounds with a warranty of 2 years for parts and seven years leak-free. The water heater has an IP25 splash-proof certification for high-quality standards.

It has a good design for wall mounting that saves your space. You only heat water when in need for precise temperature control.

7. Stiebel Eltron Tempra 24 — Best Efficiency

The Stiebel Eltron Tempra 24 Plus water heater has a continuous flow with advanced German technology that helps with steady water temperature maintenance. The flow reduces slightly if the demand for hot water exceeds capacity.

However, this won’t have an interruption in the shower’s hot water flow.

The water heater has a sleek design that saves space and energy while supplying the entire household with hot water. Unlike other tank heaters that use oil and gas and lose much energy through the vent, the tankless Stiebel Eltron doesn’t have the same challenge because it doesn’t store hot water awaiting use.

It only heats water for use when the need arises.

The water heater saves you electrical energy, and it has an auto-modulation that electronically measures the water flow. The Tempra 24 Plus uses 15-20% less energy than other traditional water heater tanks on the market.

It’s easy to operate with an electronic flow sensor that switches on the powerful interior heating system made of copper. It’s noise-free with a digital preset temperature memory button and digital temperature display.

The model is 24kW, 240V/208V, and runs with a minimum recommended household electrical service of 150A. It produces an output water temperature of 86 to 140 degrees Fahrenheit.

It has several certifications for quality purposes such as ANSI/UL, ISO 9001, CSA, and NSF/ANSI 372 compliances for lead-free operation.

8. Cobalt Aquatics Neo-Therm — Best Aquarium

Are you looking for a water heater for warming your aquarium? The Cobalt Aquatics Neo-Therm is a fully submersible electric heater with a super flat modern design and a one-touch central system that’s easy to set.

The heater has an LED display which shows the tank and the set temperature simultaneously.

It’s a very accurate water heater that works with high accuracy of plus or minus 0.5 degrees Fahrenheit and a set temperature range of 66 to 96 degrees. Adjust your temperature to 66-96, and the system will maintain heating within that set temperature value.

The heater has an ultimate safety feature that allows the shutting off before overheating. The Neo-Therm will automatically do it for you.

The heater isn’t of the same quality as its cheap counterparts on the market. It has a resin with a shatterproof outer casing that makes it safe and durable.

With the heater, you can raise your aquarium water 11 degrees above the ambient temperature, unlike their counterparts which increase with only 2-3 degrees. It’s easy to set the water heater using the one-touch system.

The heater has a full-electronic thermostat with a thermistor display for both set and tank temperature. An integrated thermal protection circuitry shuts down the heater for safety and prevention of overheating.

It comes in a super flat design for efficient heating.

9. Marey ECO150 — Best Smart Tech

The Marey ECO150 14.6kW unit is suitable for up to two points of use, with a temperature of 41 degrees Fahrenheit and a water flow of 5 GPM. The heaters are among the few German design patented water heaters made with stainless steel water channels.

They’re of high-quality components resistant to erosion, and build-ups from calcium and chlorides. The heater uses smart technology that lets the user adjust the temperature on the LCD panel, maximizing energy consumption.

They have a good design that saves on your space during installation. The water heaters are suitable for simultaneous use at two points, keeping an endless supply of hot water.

The tankless water heater is affordable, allowing everybody to enjoy an undisrupted water supply.

The water heater needs a 70-amp double pole breaker and a 220V-240V power supply. The installation should be by a qualified electrician who understands how to do it right.

When purchasing the heater, you benefit from excellent customer care and support services.

10. Portable Propane Tankless — Best Portable

No more outdoor cold baths with this type of water heater. It’s easy to use this detachable water heater to wash your pets and make them feel happy.

The water heater comes with multiple accessories such as a high-pressure showerhead, gas regulator, stainless steel shower, and hose holder. Wrenches, dust cover, garden hose, universal gas connector, and fitting kits with Teflon tapes are also included.

The water heater is easy to install with a low-pressure startup. Multiple safety protections be sure to oxygen depletion safety, overheating protection, thermal protection, anti-freezing protection, and flameout protection, including the open design for the prevention of excess surface temperature.

The tankless water heater has a good quality that provides endless hot shower to the users. The product ignition is battery-powered, which makes it applicable in different areas, including areas with no power supply.

With the water heater, there’s no preheating and waiting for hot water. You’ll enjoy your hot shower within 3 seconds.

Directly connecting to the water supply in the right position will help your family and pets enjoy a hot shower.

The water heater is small in size and doesn’t eat into your space. You only heat water on demand, which saves on energy costs.

How We Evaluated

To find the best 19 gallon water heaters, we evaluated each model across several key criteria:

Heating Performance: We assessed each heater’s ability to deliver consistent hot water at the rated temperature. Models with self-regulating technology, fast recovery rates, and reliable temperature maintenance scored highest.

Energy Efficiency: Water heating can account for over 20% of your household energy budget. We prioritized models that minimize energy waste through tankless on-demand heating, electronic flow sensing, and auto-modulation technology.

Installation and Size: Since many 19 gallon water heaters are designed for point-of-use applications, we evaluated how easy each unit is to install in confined spaces. Compact designs that fit under sinks, in closets, or on walls received higher marks.

Build Quality and Durability: We looked at construction materials including glass-lined tanks, stainless steel water channels, and corrosion-resistant components. Warranty length was also factored into our durability assessment.

Safety Features: Every water heater on our list includes essential safety features such as temperature and pressure relief valves, overheating protection, and relevant certifications like CSA, IP25, and NSF/ANSI compliance.

Value for Money: We compared the purchase price against features, warranty coverage, and long-term operating costs to determine which models offer the best overall value.

Buying Guide: Choosing the Best 19 Gallon Water Heater

Fuel Source

Most residential water heaters use either gas or electricity as an energy source. Remember to confirm if your heater uses gas as an energy source if it runs with propane or natural gas.

Gas heaters generally have an upfront cost and require ventilation for safe and healthy use. The gas heater, however, outweighs their upfront cost by their relatively low operation cost.

On the other hand, the electric heater tends to have a lower initial cost but higher operational cost than its gas counterpart. The critical thing to note when buying the heater is the type of energy available and reliable at home.

Energy Efficiency

Regardless of the energy source you choose for your heater, water heating can be among the heavy energy consumers in your home. Therefore, you need to select a new heater that doesn’t waste your energy and cut on the cost of heating your water.

A right water heater should be efficient and meeting the federal energy standards. Energy efficiency measures the effectiveness of using energy and the rate of energy loss during water heating.

Go for a water heater with a better energy factor.

Storage Type

The most popular water storage is the tank water storage system. For a tankless alternative, see our best electric tankless water heater guide. The system operates by continuous heating of water and storing it in a tank that water flows through a tap.

Cold water enters the bottom of the tank to replace hot water, so that that it’s always full. There’s a heat loss with this system because there’s continuous heating of water in the tank.