7 Best 120v Tankless Water Heater Reviews – Under Sink Electric Point of Use 2020

The tankless water heater has been essential gear for home washing or showering, and the normal types based on the voltage needed are 120v tankless water heaters for point of use as well as 240 heaters for shower use.

The small electricity supports low water flow range, that is why in this 120v tankless water heater reviews, the majority of which is the point of use or under sink use available. Apart from introducing the best 120-volt instant hot water heaters on the market of 2020, there are also experts buying guides that you can never miss.

Now, let’s start the trip!

7 Best 120v Tankless Water Heater of 2020

120 volt instant hot water heaterBosch Electric Mini-Tank Water Heater4.5
instant water heater priceStieble Eltron Point of Use Heater4.5
on demand water heater electric 120 voltEcosmart ECO Mini Heater4.6
120 volt tankless water heater reviewsCamplux ME40 Mini Tank Heater4.3
120 volt electric tankless hot water heaterEcosmart POU Heater4.0
120 volt tankless hot water heaterSio Green IR30 POU Electric Heater4.2
point of use water heater 120 voltThermoflow UT10 Electric Mini-Tank Heater4.3

120v Tankless Water Heater Reviews

#1. The Overall Best Type – Bosch Electric Mini-Tank Water Heater

120 volt instant hot water heater



Being the top pick mini-tank water heater of 120volt, this compact heater shows its brilliant performance. Maximum 7 gallons of water flow rate enables residential under sink use, supplying constant hot water for dishes washing. Its compact shape spares much space and you can mount it either vertically or horizontally under the water sink.

The maximum temperature range is 65-145 degrees F, while the thermal efficiency reaches up to 98%. For different flow rate demanded, there are multiple types, with the maximum gallons reach 2.5, 4 and 7. The gorgeous quality level fastens the output time, which, accordingly, minimizies the stand-by loss in use.

#2. Runner Up – Stieble Eltron Point of Use Heater

instant water heater price



The most praiseworthy feature of this point of use heater is the solid water temperature in shower use. it perishes the trouble of coldwater sandwich. The modern and sleek design makes it the similar like of a tank heater, yet the performance exceeds the counterpart a lot. Open up the tap and hot water flows out in a few seconds.

It requires no maintenance but lasts twice longer than tank types. The hydraulic control reduces the working noise. Small in size, it is capable of providing hot water for a shower use in a warm climate. Plus, the controller outside eases the way of setting the water temperature. In a word, it is a deal you can never miss.

#3. Best Under Sink Type – Ecosmart ECO Mini Heater

on demand water heater electric 120 volt



This is a perfect water heater for kitchen under sink use, the sleek design comes with portable size adds up home decor and also saves much space. You can opt to different models based on your demanded water flow. 99.8 percent of high energy efficiency reduces the using expense.

One knob design makes it easy to operate, you need only turn the knob for adjusting the water temperature. No matter for hand washing or cloth washing, it offers ceaseless hot water for you.

#4. Best for Point of Use – Camplux ME40 Mini Tank Heater

120 volt tankless water heater reviews



Here comes a mini tank, featuring shelf, wall or floor mounted in installation. The flow rate of it reaches 4 gallons per minute, and meet your demand for supplying hot water for daily use. Backed up by its glass-lined tank, it delivers wonderful working performance as well as long service life.

Its easy operation design is enhanced by the thermostat control, which allows adjusting water temperature by button design. The compact shape frees you from shuffling your house up and down to accommodate it.

#5. Best Small Electric Tankless Water Heater – Ecosmart POU Heater

120 volt electric tankless hot water heater



If you have little demand for water flow rate, then you may consider this model. With a maximum flow rate reaching 0.5 gallons, you can use it under the water sink for handwashing. Though small in shape, it provides consistent on-demand hot water in a few seconds. The digital panel shows error signs as well as the exact temperature of the water.

The copper and stainless steel components are equipped for high efficiency. It requires no maintenance, lasts for a relatively long time if used under recommended instructions. Costs no more than $150, you can get a modern point of use tankless water heater home.

#6. Functional 120v Tankless Water Heater – Sio Green IR30 POU Electric Heater

120 volt tankless hot water heater



This model proves to be the most functional instant water heater within $200. It is 4 level available from level 1 to 4. Adjusting the current amp from 5 to 30, you can get power from 1kw to 3.4kw, fitting any home appliance.

It adopts patented technology, preventing the hot water getting direct touch with metals, to reduce the corrosion and prolong the service life. The water flow regulator that comes with the model allows you to adjust the water temperature handily.

#7. Cheapest Water Heater – Thermoflow UT10 Electric Mini-Tank Heater

point of use water heater 120 volt



Have a tight budget? Then this model is your best option. Costs around $130, its performance far more than that. The 120v design with 2.6 gallons flow rate enables under sink hot water supply for dishwashing or handwashing. The sleek appearance with classic color matching lights up your home decor even when you hang it on the wall. Thanks to the compact shape, it occupies no much floor space for small apartment use.

The thermostop function reduces stand-by loss power consumption and enhances safety in use. EPS Foaming technology brings fast recovery rate, resulting in short waiting time for hot water.


The normal voltage of residential electric machines are of 120v and 240v; However, the types of water heaters vary a lot based on the using conditions and required water flow. In order to choose the proper one for long-term use, you need to be aware more of the types.

120v Electric Tankless Water Heater

I am sure that you are not strange to the tankless water heater, as the name suggests, it is powered mainly by electricity. For its cheap price and simple operation, most of you will take note of the electric type. Indeed, it requires less skill in installation, anyone knows the basic knowledge on installing can replace the job of the paid installer, which in other words, saves much unnecessary expense accordingly.

Plus, unlike a gas water heater and propane water heater, there is no waste gas emitting in using process, and thus no venting facilities are needed. The compact shape design of 120v electric hot water heater enables you to use it anywhere that possible, for a short hot bath or for plates washing when installing under the water sink.

120v Tankless Water Heater for RV

With the growing trend on the RV traveling, the selection of life accessories used on the RV has been a hot topic. And the primary and the most urgent need for outdoor long-term travel is hot water. You need hot water to wash the dishes messed up by a relaxing picnic; a hot bath becomes necessary after getting close touch with nature; washing the dirty clothes also requires constant clean water. Under such conditions, a 120v tankless water heater for RV is doomed to be the thing you can never miss.

Before buying the RV use heater, you need to make sure it is compatible with your vehicle. If for shower use, the flow rate and power should be high; while for under sink use, the portable and small type is enough.

120 Volt Point of Use Tankless Water Heater

The point of use heater is, to some extent, under sink water heater. It is designed small in size and low in rate, supplying the limited amount of hot water for one point use, typically for plates washing under the water sink or for washing machine use.

The under sink tankless water heater of 120v serves also as a complement of shower use water heater. The major advantage of it is the unlimited hot water you can get through the smart device. It activates only when you need it, thus no adding waste occurs; After turning the tap on, the stable hot water gushes out in few seconds.

120v Tankless Water Heater for Shower

To be honest, seldom 120v tankless water heaters are capable of supporting hot water for a relaxing bath; but for a quick bath, the low power heater is still available. Differs from the residential shower heater, 120v type serves as the ideal one for outdoor use. The portable shape spares more space; its lightweight design enables you to carry it along with you anywhere you go; the functional shower head that comes with the heating machine brings the comfy bath.

120v Hot Water Tank

What is the difference between the tank and the tankless water heater? Well, we have discussed the problem in our best tankless water heater reviews, here we make a brief introduction on the topic.

The tank water heater stores much water in its tank, and heat the stored water whenever you need it, which requires some minute to wait. While for the tankless heater, turn the tap on anytime and constant hot water flows out immediately. The difference between the tank and tankless hot water heater affects not much when you use it under the sink as a point of use machine.

120v Inline Water Heater

The inline water heater is a fast-heating device, heating the fluid passing through the device instantly. Unlike a tank or tankless water heater, it fails to maintain the temperature in a closed system, but impart heat for temporary hot water use only. The major fuel in supporting inline heater include electricity and gas. Most of which are portable and small in size, that you can use it in a shower tub, cleaning equipment or steam cleaners.

In terms of inline water heater, the sheath material and insulation types are what you should pay great attention to. Always stick to the recommended using instructions and take care in use.

Does Tankless Water Heater Use More Electricity?

Well, it depends. There are three types of the tankless water heater if we classify them according to the power source, which includes electric types, propane types, and natural gas types. The latter two models use electricity only for ignition, therefore, only electric water heaters need much electricity.

The flow rate and usages also determine the electricity needed. Compare the point of use one with the whole house use heater, the under sink saves much expense in use because the lower flow rate it needs. Aside from this, the quality and design also affect the electricity costs to a large extent. That is why you should take all the factors into considerations before buying. Read more about the products reviews and experts buying guides, and that is the best way to get the great bang for the buck.

What is a Good GPM for a Tankless Water Heater?

GPM refers to the flow rate needed in using a tank or tankless water heater, which means gallons per minute. According to the usages, the required GPM varies. For a small flow rate demanded such as under sink or point or use, it requires 1.5 GPM; Similarly, for a showerhead, you need also 1.5 GPM for a quick bath. However, if you have multiple bathrooms to use simultaneously, then the small flow rate is no longer suitable.

FixtureAverage Flow GPMAverage Temperature
Tub4.0 GPM102°F
Shower2.5 – 3.0 GPM104°F
Washing Machine2.0 GPM120°F
Dishwasher1.5 GPM110°F
Kitchen Sink1.5 GPM110°F

What Size Tankless Electric Water Heater Do I Need?

The maximum temperature rise at the given flow rate determines the water heater size. Therefore, the two factors, flow rate, and temperature rise are what you should calculate in sizing.

Step 1. Determine the flow rate

For the beginning, you should first determine where you intend to use the device, whether for a whole house or for a small under sink use? And then check the maximum number of heaters you intend to use, add up their total flow rate, which equals the desired flow rate.

For example, if expecting to run 1 shower head with a flow rate of 2.6 gallons per minute, and simultaneously run 1 faucet with 1.5 gallons per minute. Then the desired flow rate should be at least 4 gallons per minute.

Step 2. Determine the temperature rise

To calculate the desired temperature rise, you should subtract the incoming one from output temperature. Let’s say you live somewhere warm, then the demanded water heated should be around 105-115 degree. The temperature rise is around 55 degree.

120v Tankless Water Heater Accessories

Apart from the top 7 best 120v tankless water heater reviews we have given, here are also some accessories that you may need.

120v tankless water heater for rv

Ayouyue Instant Electric 120v Water Heater Showerhead

The shower head of instant hot water heater electric 120v type features 3 temperature settings, in controlling cold water from warm. The ABS plastic material allows you to take it along with ease. Long durable design enables to save much money on purchasing brand new types for a short period of use.


120 volt electric tankless water heater

SpaGuts Bath Heater Kit

The automatic smart thermostat keeps the water temperature stable. Stainless steel material enables a long service life. Placing it into a large bathtub, and it heats the water up in a short minute, providing you the constant source of hot water and bringing relaxing bathing time.