Download the Heatworks mobile app to control and monitor your hot water usage from anywhere.
$ 899 Regular price

No rust or scale. No annual maintenance. No energy efficiency loss. No worries.

The MODEL 3 is a tankless electric water heater which provides endless hot water on-demand for houses, apartments, points-of-use, and certain commercial applications. As with all tankless electric units, the MODEL 3 is highly efficient as it only uses power when hot water is needed. Install the MODEL 3 nearer to the point of use for up to 10% in water and 25-40% in energy savings each month. And because the MODEL 3 has no metal heating elements to scale and rust, it maintains its energy efficiency throughout the life of the unit.

MODEL 3

NOT ALL ELECTRIC WATER HEATERS ARE MADE THE SAME.

INTRODUCING OHMIC ARRAY TECHNOLOGY

Take a peek inside our electric tankless water heater. No metal heating elements here.

For the last 100 years, electric water heaters have been designed with one fundamental flaw: their metal heating element(s) will rust, scale and eventually fail. The MODEL 3 Water Heater is different. It uses electronic controls to pass controlled electric currents through the liquid. This transfer converts electrical energy into thermal energy, creating endless and efficient heating with temperature stability better than resistive heating elements.

ohmic array technology

Take a peek inside our electric water heater, you won’t find metal heating elements here.

With our advanced all-electric technology, the MODEL 3 is able to monitor incoming data points and make adjustments 50-60x a sec. This means we maximize energy efficiency and use less electricity to heat water.

Using graphite electrodes and electronic controls, we pass controlled electric currents through the water. This transfer of electrical energy into the water increases the thermal energy, creating heat.

With no metal heating elements to scale or fail, no maintenance is ever required. That’s why we can offer the industry's only 6-year, full-unit replacement warranty.

The MODEL 3 Water Heater is the only water heater in the world that uses Ohmic Array Technology to heat water. All others use metal heating elements, which will rust, become covered with limescale, and eventually form hotspots. This 100-year-old technology causes sediment to form in the water, poor temperature control, and because the metal heating elements have to work harder to heat water over time, wastes energy.

The best electric water heater available on the market today.

We get it. Buying a new electric water heater is about as fun as getting a tooth pulled. That’s why we designed the MODEL 3 to be the best in its class. It heats water in the simplest, purest and most efficient way.

Ohmic Array Technology

The MODEL 3 is the only water heater in the world to use Ohmic Array Technology instead of metal heating elements to rust or scale.

features-energyefficient

Energy Efficient

The MODEL 3 is highly efficient as it only uses power when hot water is needed. Install it nearer to the point of use for up to 10% in water and 25-40% in energy savings.

features-zeromaintenance

Zero Maintenance

The MODEL 3 requires NO annual maintenance or NO heating elements to change out.

features-worryfree

Worry-Free

Not only will you get endless hot water, the MODEL 3 comes with an industry-leading, 6-year full unit exchange warranty.

How many will you need?

The number of units you will need is based on several variables: How are you going to use your water heater? Where in your home will you put it? Where do you live? How much water you need at any given time?

MODEL 3

How are you going to use your water heater?
Step One: Determine how you will use and where you will put your water heater

Step Two: Determine how much hot water you need (or flow rate) at any given time then look at the map to find your location. The colors will tell you how many model 3 units you will need.

2.0 Gallons Per Minute (GPM) Flow Rate

to achieve 110° F water temperature

  • Need 1 MODEL 3 Water Heater, set at 100 A
  • Need 1 MODEL 3 Water Heater, set at 50 A

4.0 Gallons Per Minute (GPM) Flow Rate

to achieve 110° F water temperature

  • Need 2 MODEL 3 Water Heaters, both set at 100 A
  • Need 2 MODEL 3 Water Heaters, one set at 100 A and one at 50 A
  • Need 1 MODEL 3 Water Heater, set at 100 A
Average Temperature of Shallow Ground Water

Temperatures In Degrees Fahrenheit

Note: All ground water temperatures on map are weighted with winter fluctuations.

2.0 GPM flow Rate

with 110°F water temperature

  • Need 1 MODEL 3 Water Heater, set at 100A
  • Need 1 MODEL 3 Water Heater, set at 50A
Average Temperature of Shallow Ground Water

Temperatures In Degrees Fahrenheit

Note: All ground water temperatures on map are weighted with winter fluctuations.

4.0 GPM flow Rate

with 110°F water temperature

  • Need 2 MODEL 3 Water Heaters, both set at 100A
  • Need 2 MODEL 3 Water Heaters, one set at 100A and one at 50A
  • Need 1 MODEL 3 Water Heater, set at 100A
Average Temperature of Shallow Ground Water

Temperatures In Degrees Fahrenheit

Note: All ground water temperatures on map are weighted with winter fluctuations.

Control and monitor your hot water usage from anywhere.

Our WiFi-enabled mobile app allows you to remotely control the temperature of the water, monitor the amount of hot water and energy used each day in your home, and even estimate how much hot water is actually costing you. Turn the water heat down when the babysitter comes for peace of mind (or to get that teenager out of that too-long shower).

MODEL 3 app

Technical Specs


Product Information

technical specs of MODEL 3

Product Information

Weight
35 lbs.
Connections
3/4” NPT male connections
Digital Controls
LED panel, Full Wi-Fi connectivity & mobile app
Max Temp Rise
41° F rise at 4 GPM / 82° F rise at 2 GPM
Standard Warranty
6-year full unit exchange; Optional 4-year extended warranty available
Download Specs

 


Operating Ranges

technical specs of MODEL 3

Operating Ranges

Voltage
208-240 V
Frequency
50/60 Hz
Power
6.2-24 kW
Max Inlet Temp
140° F / 60° C
Working Pressure
30-80 psi / (2.06 bar-5.52 bar) 206 kPa-552 kPa
Conductivity
80-2000 µS
Current
User selectable 30-100 A
FREQUENTLY ASKED QUESTIONS

MODEL 3 FAQs

Though not required, we highly recommend that you download the Heatworks app and connect the MODEL 3 to your Wi-Fi network at the time of installation or as soon as wireless internet is available. Connecting the MODEL 3 to your Wi-Fi network will allow our team to update your MODEL 3 over-the-air, ensuring your product is always operating with the most recent version of software. Also, you will be able to take advantage of additional features such as being able to remotely control temperature settings. It should be noted that the Heatworks App is only supported on the Apple and Google Play stores. Amazon or Microsoft app stores do not have a version of the Heatworks app available currently.

No. Heatworks products are designed for use with potable water only. We do not recommend using our products with unapproved chemicals or with water containing chemicals. Please contact Heatworks before using any chemicals with your Heatworks product or using the product for any application outside of what is described in the User Guide & Installation Manual so not to void your warranty.

Yes. The MODEL 3 has a minimum activation rate of 0.4 GPM.

Some competitors have minimum activation rates up to 0.75 GPM, depending on manufacturer and model. An activation rate above 0.5 GPM means that even a low flow fixture, such as a hand sink, may not trigger the tankless water heater to begin heating. With an activation rate of 0.4 GPM, we provide our customers with hot water, even at lower demand hot water draws.

No. All Heatworks products run on AC power. You can use an inverter (which converts DC power to AC power) to run Heatworks water heaters. The inverter needs to be at least as large as the kW of power needed to produce the desired amount of hot water at the desired temperature.

Heatworks requires a licensed plumber and electrician to install the MODEL 3 water heater. In some areas, HVAC professionals may have both plumbing and electrical licenses under the same roof. It is required that any licensed installer read the User Guide and Installation Manual prior to installing the unit. Additionally, all water lines in the plumbing system need to be flushed of debris entirely before installing the MODEL 3 for both retro-fit and new construction projects. This is required to keep all foreign matter from entering the MODEL 3. Failure to do so prior to installing the MODEL 3 will void the warranty.

Unfortunately, we cannot provide you with an exact cost of operation as that number will vary depending on your location and application. The MODEL 3 is a non-continuous device and only draws power when there is a need for hot water. Meaning, the MODEL 3 does not continue to draw power once hot water is turned off. 

The MODEL 3 is built to perform. Unlike other water heaters, it can be adjusted from 30-100 A upon installation, depending on your specific hot water needs. The higher the power setting, the more hot water you can expect.

For a unit set to 30 amps:

    - 4 gallon per minute demand will yield a 12° F rise in temperature.
    - 3 gallon per minute demand will yield a 16° F rise in temperature.
    - 2 gallon per minute demand will yield a 24° F rise in temperature.
    - 1.25 gallon per minute demand will yield a 39° F rise in temperature.

For a unit set to 50 amps:

    - 4 gallon per minute demand will yield a 20.5° F rise in temperature.
    - 3 gallon per minute demand will yield a 27° F rise in temperature.
    - 2 gallon per minute demand will yield a 41° F rise in temperature.
    - 1.25 gallon per minute demand will yield a 65° F rise in temperature.

For a unit set to 100 amps:

    - 4 gallon per minute demand will yield a 41° F rise in temperature.
    - 3 gallon per minute demand will yield a 54° F rise in temperature.
    - 2 gallon per minute demand will yield a 82° F rise in temperature.
    - 1.25 gallon per minute demand will yield a 131° F rise in temperature. 

Click here to download the MODEL 3 Expected Temperature Rise chart to see what temperature rises you can expect at different voltages, amperages, and flow rates.

Your water company can come test your water, or you can purchase a water conductivity meter that can give you a reading in as little as 5 seconds. We recommend ordering one from Amazon.

No, not at this time. Pool water heaters fall under a different category of UL standards and are tested accordingly. We have not yet tested the MODEL 3 as a pool heater; however, we do plan to put our units through the appropriate UL testing for this application when possible.

No. We have not yet tested our products for specific use on boats. Further, salt water should never be heated with any Heatworks products.

No, not currently. We have not yet tested our products with fish tanks.

No. Heatworks products will not function properly with GFCI, GFI, RCB, RCD, or any other ground-fault breakers. Because the water coming out of our products is grounded, there are current characteristics unique to the water heaters that cause these types of breaker to trip when the unit first powers up. We do not recommend using ground-fault breakers with Heatworks products.

No. At this time, the MODEL 3 is only certified to be installed within the United States. Any installations outside of the United States will void the MODEL 3's warranty. While we do plan on selling the MODEL 3 internationally, we do not yet have a timeline for when that will occur, unfortunately. If you would like to check in for updates, please sign up for our mailing list. You can do so at the bottom of this page!

You’re correct. Unlike other water heaters, the MODEL 3 can be adjusted from 30-100 A upon installation, depending on your specific hot water needs. The higher the power setting, the more hot water you can expect. We have found that inspectors tend to rate the MODEL 3 assuming its maximum power, 100 A. As a general rule, electric tankless water heaters shouldn’t exceed 50% of the service to the home. So, assuming yours is at 200 A, you should be fine. We always recommend hiring an electrician to do a load analysis to confirm. For more information, refer to the National Electric Code (also known as NFPA 70).

Once your MODEL 3 is installed, we do not recommend changing the current setting. (The current setting can be found underneath the unit; the installer should have circled the maximum current he selected in which the unit could be used.) Keep in mind your installer chose the breaker and branch circuit wires according to this maximum, which is particularly important to avoid over heating of the wires. This will cause nuisance or premature breaker trips.

No. According the NEC 220-83, the MODEL 3 is considered a non-continuous heating appliance. This means the MODEL 3 load is generally added to the service load at only 40% of its maximum nameplate rating. So if you choose to use the MODEL 3 at its maximum power, 100 A, 40% of this rating is 40 A. The 40 A is typically the load added to the overall service load of the dwelling, not the full load current rating of 100 A. Keep in mind that the conventional electric water heater that you are replacing is probably rated for use on a 30 A circuit and draws 4.5 kW or 18.75 A. Using the same calculation method, 40% of the nameplate rating for a conventional 4.5 kW electric tank water heater is 7.5 A. So, one MODEL 3 will add 32.5 A (40 A minus 7.5 A) additional amps to the service load since 7.5 A were already available for the existing tank.

No. The installer will determine the maximum power setting (between 30 A and 100 A) and should use the appropriate wiring based on that setting. Please refer to page 17 of the MODEL 3 Users Guide and Installation Manual for the wiring table.

Compare Top Electric Water Heaters

Whether you are replacing an old water heater, building a new home, or adding to an existing one, there are several things you should to compare before deciding on an electric water heater. Tank vs tankless water heaters, energy efficiency and reliability are just a few.

Heatworks Model 3 for compare

Heatworks Model 3 Tankless Electric Water Heater

Type

Tankless

Heating Technology

Ohmic Array Technology

Wi-Fi Enabled

Yes

Maximum Temperature Rise

41° F at 4 GPM, 82° F at 2 GPM

Energy Efficiency

.94 UEF for the life of the unit

Minimal Flow Rate Required

.4 GPM

Size

11“ x 16.5” x 10”

Standard Warranty

6-year full unit exchange — No need to call a plumber or electrician, just ship the unit back and we give you a new replacement.

Maintenance Required

No maintenance required.

Mobile App

Yes

Amperage

100 A

Continuous Hot Water

Yes

Single Shower Length

Unlimited

Uses Electricity at All Times

No, only when there is a hot water draw.

Heatworks Model 3 for compare

Stiebel Eltron 24kW Plus Electric Water Heater

Type

Tankless

Heating Technology

Metal Heating Elements

Wi-Fi Enabled

No

Maximum Temperature Rise

41° F at 4 GPM, 82° F at 2 GPM

Energy Efficiency

.94 UEF, scaling can reduce efficiency by up to 50%2

Minimal Flow Rate Required

.5 GPM

Size

16.625" x 14.5" x 4.625"

Standard Warranty

7-year limited warrany against leakage, 3-year limited warranty against defects in workmanship and materials.

Maintenance Required

Scale build-up may need to be flushed from the unit every six months to a year. Elements may need to be replaced.

Mobile App

No

Amperage

2 x 50 A

Continuous Hot Water

Yes

Single Shower Length

Unlimited

Uses Electricity at All Times

No, only when there is a hot water draw.

Tru Tankless 24kW Electric Water Heater for compare

Trutankless 24kW Electric Water Heater

Type

Tankless

Heating Technology

Metal Heating Elements

Wi-Fi Enabled

Yes

Maximum Temperature Rise

40° F at 4 GPM, 75° F at 2 GPM

Energy Efficiency

.94 UEF, scaling can reduce efficiency by up to 50%2

Minimal Flow Rate Required

.2 GPM

Size

23.74" x 17.2" x 5.5"

Standard Warranty

2-year limited warranty on labor and 5-year limited warranty on parts.

Maintenance Required

Scale build-up may need to be flushed from the unit every six months to a year. Elements may need to be replaced.

Mobile App

Yes

Amperage

100 A

Continuous Hot Water

Yes

Single Shower Length

Unlimited

Uses Electricity at All Times

No, only when there is a hot water draw.

Rheem Performance 40-Gallon Electric Water Heater for compare

Rheem Performance 40-Gallon Electric Water Heater

Type

Tank

Heating Technology

Metal Heating Elements

Wi-Fi Enabled

No

Maximum Temperature Rise

N/A

Energy Efficiency

.94 UEF, scaling can reduce efficiency by up to 50%2

Minimal Flow Rate Required

N/A

Size

20.25" x 48.5" x 20.25“

Standard Warranty

6-year limited warranty on tank and parts. 1-year in home labor warranty.

Maintenance Required

Scale build-up may need to be flushed from the unit every six months to a year. Elements may need to be replaced.

Mobile App

No

Amperage

18.75 A

Continuous Hot Water

No

Single Shower Length

53 Gallons

Uses Electricity at All Times

Yes

A.O. Smith Signature 50-Gallon Electric Water Heater for compare

A.O. Smith Signature 50-Gallon Electric Water Heater

Type

Tank

Heating Technology

Metal Heating Elements

Wi-Fi Enabled

No

Maximum Temperature Rise

N/A

Energy Efficiency

.94 UEF, scaling can reduce efficiency by up to 50%2

Minimal Flow Rate Required

N/A

Size

64" x 20“

Standard Warranty

6-year limited warranty

Maintenance Required

Scale build-up may need to be flushed from the unit every six months to a year. Elements may need to be replaced.

Mobile App

No

Amperage

30 A

Continuous Hot Water

No

Single Shower Length

45 Gallons

Uses Electricity at All Times

Yes

A.O. Smith Signature 40-Gallon Electric Water Heater for compare

A.O. Smith Signature 40-Gallon Electric Water Heater

Type

Tank

Heating Technology

Metal Heating Elements

Wi-Fi Enabled

No

Maximum Temperature Rise

N/A

Energy Efficiency

.94 UEF, scaling can reduce efficiency by up to 50%2

Minimal Flow Rate Required

N/A

Size

49.75" x 20.5“

Standard Warranty

6-year limited warranty

Maintenance Required

Scale build-up may need to be flushed from the unit every six months to a year. Elements may need to be replaced.

Mobile App

No

Amperage

30 A

Continuous Hot Water

No

Single Shower Length

37 Gallons

Uses Electricity at All Times

Yes

2A recent study found that over time, scale deposits can reduce the energy efficiency of water heating elements by up to 50%. Source: http://www.cwt-international.com/cwt/images/stories/Download/Vulcan/EN_How_Scale_Is_Killing_Heating_Efficiency.pdf

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Still Have Questions?

Get in touch with our customer service team today. We'd love to help!