# How Many Amps Does A Tankless Hot Water Heater Use

## How Many Amps Does A Tankless Water Heater Use? (42-167 Amps)

Electric tankless heaters heat water solely with electricity and do not need any other fuel. As we all know, boiling water is a time-consuming and difficult operation. As a result, electric tankless water heaters demand a large amount of electricity current, measured in amps. Tankless water heaters consume a certain amount of electricity. Tankless heaters may draw anywhere from 42 amps to 167 amps, depending on their size. We can compute exactly how many amps a tankless water heater consumes since we understand two important factors:

1. The total amount of power, measured in watts. Voltage and power input for electric tankless water heaters can range from 10,000W (10 kW) to 40,000W (40 kW)
2. And temperature. All electric tankless water heaters run on a 240-volt circuit in order to limit the amount of electricity consumed.

In order to compute the using the electric power equation (P = IV), we must first express the I (or electric current) in the following way: (amps) = P(watts)/ (volts) (volts) Example: Consider the following scenario: a 30 kW tankless water heater is connected to a 240-volt circuit. In what range of amps does a 30 kW tankless water heater operate at? The electrical power equation is used in the following manner: It is calculated as follows: I(amps)=30,000W/240V = 125 amps A heater of this nature consumes 125 amps (you need several 20-amp or 30-amp breakers for installation).

## How Many Amps Do 10-40 kW Electric Tankless Water Heaters Draw?

All of these estimates are based on the assumption that the heater is powered by a 240-volt circuit.

 Tankless Heater Size (in kW) Electrical Current (in Amps) 10 kW 42 amps 11 kW 46 amps 12 kW 50 amps 13 kW 54 amps 14 kW 58 amps 15 kW 63 amps 16 kW 67 amps 17 kW 71 amps 18 kW 75 amps 19 kW 79 amps 20 kW 83 amps 21 kW 88 amps 22 kW 92 amps 23 kW 96 amps 24 kW 100 amps 25 kW 104 amps 26 kW 108 amps 27 kW 113 amps 28 kW 117 amps 29 kW 121 amps 30 kW 125 amps 31 kW 129 amps 32 kW 133 amps 33 kW 138 amps 34 kW 142 amps 35 kW 146 amps 36 kW 150 amps 37 kW 154 amps 38 kW 158 amps 39 kW 163 amps 40 kW 167 amps

You can correctly determine how many amps your tankless hot water heater consumes by using this amp draw table. After that, you can figure up how many amp breakers you’ll need for the installation process. For those looking for a tankless water heater, you can see our list of the best tankless water heaters right here.

## How many amps does a tankless water heater draw?

This amp draw chart can help you determine how many amps your tankless hot water heater consumes with accuracy. After that, you can figure up how many amp breakers you’ll need for the installation. If you’re in the market for a tankless water heater, have a look at our list of the finest tankless systems right now.

• When a tank water heater with 4,500-watt elements is operated on 10 wires and a 30-amp circuit breaker, the overall electrical load is 28,000 watts
• When a whole-house tankless water heater is operated on four, 7,000-watt elements, the total electrical load is 28,000. This load necessitates the installation of cable and a circuit breaker capable of handling at least 120 amps, at a cost that is several times more than that of providing electrical service to a traditional tank water heater.

So, how much electricity does a tankless water heater consume? In order to function properly, the average electric tankless water heater requires at least 120 amps. Unfortunately, the overall capacity of the ordinary home is just 200 amps. You’ll have to improve your electrical system to match the increased load demand, which is what it really implies. Not only that, but the increased load would need the installation of a larger, more expensive meter loop and main panel for the residence. Nonetheless, you as the end customer may be responsible for the cost of the wire that connects the neighborhood distribution transformer and the electric meter.

1. You can figure out how many amps your tankless water heater consumes by doing some math on your own.
2. A typical electric tankless water heater may produce power of between 10,000 watts (10 kW) to 40, 000 watts (40, 000 kW) (40 kW).
3. In order to compute the using the electric power equation (P = IV), we must first express the I (or electric current) in the following way: (amps) = P(watts)/ (volts) (volts) Example: Consider the following scenario: a 30 kW tankless water heater is connected to a 240-volt circuit.
4. The electrical power equation is used in the following manner: It is calculated as follows: I(amps)=30,000W/240V = 125 amps A heater of this nature consumes 125 amps (you need several 20-amp or 30-amp breakers for installation).

It is self-explanatory in terms of the amount of amps that your tankless water heater will consume, and it is based on the calculation described above.

 Tankless Heater Size (in kW) Electrical Current (in Amps) 10 kW 42 amps 11 kW 46 amps 12 kW 50 amps 13 kW 54 amps 14 kW 58 amps 15 kW 63 amps 16 kW 67 amps 17 kW 71 amps 18 kW 75 amps 19 kW 79 amps 20 kW 83 amps 21 kW 88 amps 22 kW 92 amps 23 kW 96 amps 24 kW 100 amps 25 kW 104 amps 26 kW 108 amps 27 kW 113 amps 28 kW 117 amps 29 kW 121 amps 30 kW 125 amps 31 kW 129 amps 32 kW 133 amps 33 kW 138 amps 34 kW 142 amps 35 kW 146 amps 36 kW 150 amps 37 kW 154 amps 38 kW 158 amps 39 kW 163 amps 40 kW 167 amps

HVAC Metrix (Heating, Ventilation, and Air Conditioning) The SEER equation is (1 EER100 percent + 42 EER75 percent + 45 EER50 percent + 12 EER250 percent)/100EER = BTUcooling/WHSPF = BTUheating/WCOP = Q (useful heat)/WCOP = Q (useful heat)/WCOP = Q (useful heat)/WCOP = Q (useful heat) (input work) Air conditioning capacity (ACH) = CFM x 60/Area x Heightceiling CFM x h = 4.5 times the total heat (BTU/hr) (std.

1. air) Temperature Sensitive Heat (BTU/hr) = 1.1 times the CFM times the time (std.
2. air) 1 horsepower is equal to 746 watts.
3. o, you might be thinking, how can I determine whether or not my home’s electrical system need an upgrade, right?
4. Just so you’re aware, if you’re intending to replace your conventional water heater with a tankless equivalent in your existing house, the installation costs will be significantly more than they would have been if you’d chosen to build the tankless heater from scratch.
5. What would be the result of this?
6. Low voltage or rapid voltage reductions, on the other hand, are likely to result in dimming or flickering lights, as well as a variety of other issues.
7. Trust me, I’ve encountered issues such as flashing lights in the past, and after conducting a root cause study, I discovered that connecting 28-kW tankless units in houses with 150-amp services to 10-kW transformers was a clerical error on my part.

## Gas Tankless vs. Electric Tankless: Which model requires up-gradation of a home electric system?

To put it another way, it ALL DEPENDS. But, I’m confident that you aren’t here to accept this response, are you? Let’s conduct some further study and delve a little deeper into the subject. Simply said, based on my knowledge and experience, I can state that a gas tankless system does not often necessitate the upgrade of a home’s electric system, as an electric tankless system does. I believe this is true. Also important to note is that the majority of the gas tankless water heaters that we’ve examined on this blog have earned the Energy Star certification, and many of them are even eligible for federal tax incentives.

## How many amps does a Rinnai tankless water heater use?

To be quite honest, Rinnai tankless water heaters are among the finest in their respective categories.

The firm has proven its mettle time and time again by supplying cost-effective, high-efficiency goods, such as tankless water heaters, to its customers. Rinnai Tankless Water Heaters require 120 volts alternating current at 60 hertz and less than three amps to operate.

## Are tankless water heaters 110 or 220?

Tankless water heaters are available in both 110V and 220V types, so you’ll be able to pick one that suits your needs. As a result, you may select the one that is most compatible with your household electrical requirements. Most of the power consumed by the tiny tankless heaters, such as those used at the point of use or beneath the sink, is 110V. The powerful tankless heaters designed for commercial use, on the other hand, require significantly higher voltages to operate.

## How many amps is a 50-gallon water heater?

A common electric tankless water heater operates at a maximum power of 4500 watts. Many of you may not be aware that 4500 watts is equal to 18.75 amps in a 240-volt electric circuit, which is something that many of us take for granted.

## Are most hot water heaters 220?

The majority of electric hot water heaters operate on alternating current (AC) voltages ranging from 220 to 250 volts. When purchasing a tankless water heater for your house that operates on 220 volts, you should be aware that this voltage in a home necessitates the installation of a double circuit breaker rated for the amperage demand of the hot water heater.

## How many BTUsdo I need for atankless water heater?

Due to the significant amount of gas required to heat the water to an appropriate temperature (usually between 150,000 and 200,000BTUs), an average home would require an upgrade in the size of the gas line to accommodate this requirement.

## How many amps does an electric hot water heater use?

The majority of the electric tankless hot water heaters that we’ve tested on our site so far have required a dedicated 30-amp, 240-volt circuit breaker to function properly. The use of an electric water heater necessitates the installation of a 240-volt dedicated circuit that serves just the water heater and no other appliances or devices. In most cases, the circuit wiring will consist of a 30-amp double-polebreaker and 10-2 non-metallic (NM) or multi-conductor (MC) cable.

## What size breaker do I need for a 40-gallon electric water heater?

To be honest, the average residential 30- or 40-gallon water heater consumes approximately 4500 watts, and if my memory serves me correctly, they are typically powered by a 30 A circuit breaker.

## What size breaker do I need for a 4500-watt water heater?

The breaker is designed for 30 amps because this is an entirely resistive load (5500 watts at 240 voltage equals 23 amps), and the wire is 10 AWG because this is a completely resistive load. Using your example, the elements are strapped for 4500 watts, which results in 18.75 amps of permanent draw. Permanent draw loads should be designed at 80 percent of breaker capacity, therefore a 20 amp breaker is only capable of delivering 16 amps of permanent draw.

## What size breaker do I need for a 3000-watt water heater?

240 volts may be supplied via a 14/2 cable and a 15 amp double pole breaker, which can power a 3000-watt induction motor.

## What size breaker do I need for a 7500-watt heater?

7500 watts divided by 240 volts equals 31 amps, requiring a 40 amp circuit breaker.

## What size breaker do I need for a 5500-watt water heater?

According to the calculations, a 5500-watt water heater is well within the safe maximum for a 30 amp breaker and a 10-gauge electrical cable.

When the temperature of a circuit breaker exceeds its rating, the circuit breaker trips. A 30 amp breaker with a 10 gauge wire has an 80 percent safe maximum of 24 amps, which is equivalent to 24 amps. 24 amps multiplied by 240 volts equals a safe maximum of 5760 watts.

## Does an electric water heater require a disconnect?

An electric water heater does not require any type of disconnect other than a circuit breaker at the main panel or sub panel, nor does it require to be visible, according to the National Electrical Code (NEC).

## Wrapping Up

First and foremost, I’d want to express my gratitude for remaining with us to the very end. Second, I would like to bring your attention to the fact that I, along with my core team, have attempted to answer some of the frequently asked questions, such as how many amps does a tankless water heater draw, in the most accurate and thorough manner that we were able. I hope you find this information useful. And, if you were pleased with our efforts and would like to express your gratitude to us, all you need to do is forward this information to those who could benefit from it.

• Will Vinegar cause harm to a hot water heater if used? This article will cover all of the basics of tankless water heaters. Is it possible to run out of hot water while using a tankless water heater? I’m not sure what size tankless water heater I need. Is it worthwhile to invest in a tankless water heater? Will a single tankless water heater be sufficient for my home? The advantages and disadvantages of tankless water heaters
• How long does it take for a tankless water heater to pay for itself to become profitable?

## How Many Amps Does a Tankless Water Heater Use

In the event that your heating or air conditioning system requires repair or replacement, we can link you with a dependable and cost-effective specialist in your region. Tankless water heaters are fantastic since they don’t take up much storage space (just a third of a 10-gallon tank), but they’re also great because they save you money on electricity and fuel. Tankless water heaters use less fuel and water than traditional water heaters since they provide hot water on demand. Tankless water heaters, regardless of the type of device you pick (gas or electric), can save you 30 percent to 50 percent on your energy cost by reducing your water usage.

## How many amps do tankless water heaters need?

Before you can decide between a gas tankless water heater and an electric tankless water heater, you must first gather all of your information. In certain cases, a gas type may be more suitable for your household, whilst an electric tankless unit may be the best option for your home in other cases. Due to the fact that gas-fired devices run on gas (propane or natural gas), it goes without saying that their amperage requirements differ from those of electric-powered equipment. Continue reading for more information.

## How many amps does a gas tankless water heater use?

Choosing between a gas and an electric tankless water heater is a difficult decision that requires a lot of thought. In certain cases, a gas model may be more suitable for your household, whilst an electric tankless unit may be the best option for your residence in other cases. The fact that gas-fired units run on gas (propane or natural gas) makes it evident that they have different electrical demands than electric units. The specifics may be found by continuing to read.

## How many amps do electric tankless water heaters require?

Given that tankless water heaters only use fuel while you are actively utilizing the hot water, it stands to reason that you will use less fuel and energy overall. A conventional electric tankless water heater requires at least 120amps to operate, with a total capacity of 200amps for a typical family of four people. If you decide to go with electric tankless water heaters, you should consider the following considerations:

• Voltage- a large number of manufacturers provide devices that accept 110V, 120V, 208V, 220V, 240V, or 277V. When it comes to amp draw, different electric tankless units have varying demands on their power supply. It doesn’t matter which route you go, you should always make sure that your home can handle the electrical needs of your water heater. Circuit breaker- It is very necessary to have a circuit or circuits that are specifically designed to handle the electric water heater. It may even be necessary to connect the water heater to a separate circuit or circuits in some cases.

The fact that you’ll need to modify your electrical system to accommodate a higher load demand makes reasonable, and you’ll likely find yourself out \$1,500 in your pocket rather shortly. Not to mention that special equipment for electric tankless water heaters needs to be placed at the meter base in order for them to work. Increase the budget by \$2,000, which makes the electric tankless water heaters appear to be more costly than the standard electric water heaters on the market. For electric tankless water heaters, the breaker size and wire gauge must conform with the municipal, state, provincial, and national electrical codes that apply in your jurisdiction.

It is important to remember that the wiring must be sturdy enough to ensure a voltage drop of less than 3% while the system is under load.

Recently released types of classic tank-style water heaters have excelled with their efficiency, achieving an impressive 0.94 energy factor on average.

If you already have a large number of electrical equipment in your house, it is likely that you will want a more extensive electrical service than you already have.

It does not rule out the possibility of purchasing an electric tankless water heater. All that is required is an update to the electrical service, which should not be done before consulting with a competent electrician for a price.

## Can we get an example for a better understanding?

Because there are several varieties of tankless water heaters to pick from, both gas and electric, it is beneficial to have a general concept of what is available.

• A 24kW electric device with a 3.3GPM power output and a temperature increase of 50 degrees Celsius. The temperature of the groundwater is 55 degrees, but the maximum temperature at 3.3GPM will be 105 degrees.

According to the manufacturer, the machine requires a minimum of a 300-amp power supply. It is essential to provide 240V power at 100amps and to install two 60-amp circuit breakers as well as two lines of no.6 copper wire in order to complete the project. We should point you that the device will not be a light load, even when connected to a 300-amp service panel.

• With the same specifications as the previous unit: 50-degree increase and an exit water temperature of 105 degrees, a 36kW unit rated at 4.9GPM may be used.

4.9gallon capacity may be achieved by using 150 amps of 240-voltage power, three lines of no.6 copper wire, and three 60-amp breakers. Before installing a tankless water heater in an older home, it is necessary to improve the electrical supply to the home. Not all improvements are pricey, but many of them are time-consuming and take a toll on your wallet’s resources.

## One last thought

When it comes to amperage needs, different kinds of electric tankless water heaters will have varying requirements. Before making an order for an electrical device, be sure that the amperage specifications are correct. In the case of gas models, the amperage needs aren’t as critical as they are in the case of electric ones, but you should still look into the venting possibilities. It is, without a doubt, a lot of labor in both circumstances! We are confident in our ability to link you with a reputable service in your region that can repair, replace, or maintain your heating and air conditioning systems.

## How many amps does a gas tankless water heater use?

When it comes to amperage requirements, different kinds of electric tankless water heaters will have varied needs. Before placing an order for an electrical device, make sure to thoroughly examine the amperage specifications. For gas versions, the amperage needs aren’t as critical as they are for electric devices, but you should still look into the venting possibilities. Yes, both situations need a significant amount of effort. Repair, replacement, and maintenance of your heating and air conditioning systems may all be handled by a reputable service company in your region.

## How many amps does a tankless water heater need?

What is the minimum amperage need for a tankless water heater? Unfortunately, the average electric tankless water heater requires at least 120 amps to run, while the average household has a total capacity of 200 amps, making it inefficient. Because of this, you will need to improve your electrical system in order to meet the increased load demand, which might cost you up to \$1,500 in total. For a tankless water heater, what size circuit breaker am I looking for? A gas tankless water heater only requires a dedicated single-pole breaker with a 15-amp, 120-volt rating for this reason.

Advice from the experts: A single electric gadget may consume up to 36KW(!) of electricity, or a maximum power consumption of 150 Amps.

However, it is only suitable for a small home of 1-2 people and can only produce 2 gallons per minute, limiting its use.

What kind of servicing do you need for a tankless water heater? Typically, tankless heaters do not work effectively on services with currents less than 200A, and in many circumstances, an upgrade to a 320A service is required.

## How many amps does a tankless water heater need? – Related Questions

The power supply requirements for a Rinnai Tankless Water Heater are as follows: Rinnai Tankless Water Heaters operate on 120 volts alternating current at 60 hertz and draw less than three amps.

### What is the downside of an electric tankless water heater?

Tankless water heaters provide an infinite supply of hot water while taking up less space, posing a reduced danger of leaking, being safer, and having an overall lifespan that is substantially longer than conventional water heaters. The most important drawback of tankless water heaters is that their upfront cost (both for the device and for installation) is substantially greater than that of tank-style water heaters (see chart below).

### Does a tankless water heater need its own breaker?

Until recently, installing that sort of heater would have necessitated the addition of three circuit breakers to the inside panel as well as the inclusion of three new circuits. The majority of homes do not have three available slots in the circuit breaker panel, which would allow for the installation of a tankless heater.

### How many amps does a 80 gallon water heater pull?

This is something that should be looked at first. A water heater will only draw the amount of electricity required by the wattage of the element (s). As a result, your WH is equipped with two 4500 watt elements. When only one is in use, it consumes around 22 amps (208 is nominal voltage which is what you have in your building) 4500 divided by 208 equals 21.6 amps.

### What are the electrical requirements for a gas tankless water heater?

Most tankless gas water heaters require a 120-volt circuit with a 15-ampere or 20-ampere rating to power the electric pilot light and control board, respectively. The National Electrical Code specifies that instantaneous water heaters have circuits that are not more than 120 amperes in current and that are not more than 150 amperes in current protection.

### Do they make a 30 amp tankless water heater?

Tankless water heater Chronomite SR-30/240 HTR, 240-Volt 30-Amp SR Series Instant-Flow Standard-Flow Tankless Water Heater, Model SR-30/240 HTR.

### Does a tankless water heater use a lot of electricity?

What is the electricity consumption of a tankless water heater? As reported by the Department of Energy, tankless water heaters are between 24 and 34 percent more energy efficient than tank-style heaters in homes that use 41 gallons or less of hot water per day, and between 8 and 14 percent more efficient than tank-style heaters in homes that use 86 gallons or more per day.

### How many amps does a 40 gallon water heater use?

If a 2500w heater is connected to 240v, it will consume 2500/240 or 18.75 Amps and either 25 or 30 Amps, depending on the code.

### Does tankless water heater use more electricity?

Households that consume 41 gallons or less of hot water per day can benefit from tankless water heaters, which can be 24-34 percent more energy efficient than traditional water heaters. According to Energy.gov, installing a tankless heater at each hot water outlet can improve tankless water heater energy savings by as much as 27 to 50 percent, depending on the model.

### What voltage does a tankless hot water heater use?

Tankless heaters are available in a variety of sizes. There are tiny water heater units that are meant for point-of-use and only require 110 volts, as well as larger water heater units that can heat enough hot water to supply an entire family with hot water.

### What size tankless water heater do I need for a family of 5?

In summary, if you live in the northern portion of the United States, where the input water temperature is lower, you would require a 10 GPM gas tankless heater or a 27 kW electric tankless heater.

The tankless heater needs to work extra hard to raise the water temperature to 110°F or 120°F, depending on the situation.

### Can a tankless water heater fill a tub?

Filling a large tub with water from a tiny tankless water heater might take a long time. Two smaller water heaters can perform the same function as one larger water heater.

### Can tankless water heater heat whole house?

Although they are designed for frigid climates, these energy-efficient machines can offer both domestic hot water and whole-home heating. Tankless water heaters are a tried-and-true technology that has been used for many years to heat domestic hot water (see “Installing On-Demand Water Heaters,” February 2006).

### Does a tankless water heater need to be on a GFCI?

GFCI protection is required in a garage for every 120, 15 and 20 Amp receptacle outlet, which means that if you install a tankless water heater in the garage, it should also be protected by this standard.

### What size breaker do I need for a Rheem tankless water heater?

The unit requires a dedicated 40 AMP breaker and is 10 inches high by 7-1/4 inches wide by 3-1/4 inches deep. Hot water in less time!

### What wire do I use for a 30 amp breaker?

THUMB RULES AND REGULATIONS These are the rules of thumb that many techs will repeat over and over again and rely on in all situations: “Twelve-gauge wire is good for 20 amps, 10-gauge wire is good for 30 amps, 8-gauge is good for 40 amps, and 6-gauge is good for 55 amps,” and “The circuit breakers or fuses are always sized in order to protect the conductor.”

### How many amps does a 6 gallon hot water heater draw?

Residential Mini Tank Water Heater with a capacity of 6 gallons and a voltage of 120 volts and 16.7 amps.

### What size breaker do I need for a 20 gallon electric water heater?

Electric water heaters necessitate the installation of a 240-volt dedicated circuit that serves only the water heater and none of the other appliances or devices on the circuit. In most cases, the circuit wiring will consist of a 30-amp double-pole breaker and 10-2 non-metallic (NM) or multi-conductor (MC) cable.

### Are all electric water heaters 240 volts?

240 volts is the voltage used by the majority of domestic electric water heaters. Single element water heaters that run on 120 volts are available, as are single element water heaters that operate on 240 volts, among other options. The voltage rating of your water heater may be found on the label of the appliance. Breakers are often labeled; nevertheless, they might be labeled incorrectly in some cases.

### Can I use a 40 amp breaker for water heater?

It is not possible to use a 40A breaker on a 10 wire circuit. Replace the 30A breaker with a 40A breaker if you are confident that all of the wires from the breaker to the water heater are (at least) 8 gauge. However, only if you have checked the size of the wires across the whole circuit should you do so.

### How long will a tankless water heater last?

It is estimated that most tankless water heaters will last more than 20 years in normal use. They also contain easily changeable parts, which allows them to last for many more years than conventional models. Storage water heaters, on the other hand, have a lifespan of 10–15 years.

## The Big Draw of Tankless Electric Water Heaters

Tankless water heaters are an energy-efficient choice for households, and some new versions can lower home water-heating expenses by as much as 50%, according to the Environmental Protection Agency. Tankless heaters provide the ease of on-demand heating since they do not require the usage of a storage tank. Water is heated just when it is needed, rather than being heated and kept for hours as is the case with a standard tank. This decreases the amount of energy lost by sitting water and also ensures that you get a warm shower even if you’re the last person in line.

1. The majority of them may be wall-mounted either inside or outside the residence.
2. In addition, with today’s tankless systems, you may manage the temperature of the water using a digital controller.
3. For example, the EcoSmart tankless water heaters from Rheem will change the amount of energy input required based on the amount of hot water that is required at any given time.
4. Important to keep in mind when installing a gas-fired tankless heater is that the exhaust and air intake must be vented outdoors, independently from all other appliances, which can make installation more difficult.
5. To give an example, the EHT team recently investigated the possibility of installing a new tankless heater at one of our project houses.
6. The downstairs apartment appeared to be an excellent option for an EcoSmart Eco-18 unit, which would have been large enough to accommodate two bathrooms and up to three people.
7. Why?

In order to install the Eco-18 model, two 40-amp breakers were required, and the unit used 75 amps.

If the tankless unit were to turn on at the same time as another high-amp item, like an air conditioner, the lights in the house would begin to flicker and the electrical supply may become too stressed to keep everything running smoothly, according to him.

“Can you tell me how much it would cost to enhance the electricity capacity of my house?” He responded with “thousands,” and then on to complain about municipal permits, city inspectors, and other issues.

Evaluating the Electrical Supply in a Residence Before purchasing a new electric tankless heater, homeowners should consult with an electrician to ensure that the unit will be a good fit with their home’s electrical supply.

According to the amperage of a home’s electrical service, the number of appliances that may be operated at the same time is limited.

Installation of the EcoSmart Eco-18 model necessitates the use of two 40-amp breakers due to its 75-amp demand.

Essentially, an electrical conduit is a pipe that enters a house from either an underground main electric line or an above-ground service.

As a result, many conduits are larger, and a 2-inch conduit may be capable of carrying a 60-amp service.

The electrical capacity of a service wire that is visible may also be determined by looking at it.

(Caution: Do not come into contact with any exposed wires.) Additionally, the amperage rating of the electrical meter may be written on the face or body of the device.

This label may have been given by the manufacturer or affixed by an electrician during installation.

You will have one primary breaker, which will be the largest of the three, and it should have its capacity marked on or adjacent to it.

The most accurate method of determining the amperage rating is to contact with a professional electrician who will examine your electrical meter as well as the labels on your main breaker or fuse box.

Your electrician should analyze all of the information to establish the amperage rating that is most appropriate.

The lowest number represents the electrical service capacity of your home, and this information can assist you in selecting a tankless electric water heater that is appropriate for your home’s electrical service capacity.

## Side Note

The use of tankless water heaters is an energy-efficient choice for homes, with some modern models able to lower residential water-heating expenses by as much as 50%. Tankless heaters provide the ease of on-demand heating since they do not require the usage of a storage tank. In contrast to a standard tank, where water is heated and kept for hours, the water is heated as it is required. If you’re the last person in line, you’ll still get a warm shower since the energy waste from sitting water is reduced.

1. In most cases, they may be fixed on walls either inside or outside the residence.
2. A digital controller is also available with today’s tankless systems, allowing you to precisely manage the water temperature.
3. In the case of Rheem’s EcoSmart tankless water heaters, for example, the amount of energy input required will vary depending on the amount of hot water required.
4. It is important to note that gas-fired tankless heaters require the exhaust and air intake to be vented outdoors, independently from all other appliances, which might make installation more difficult and time-consuming.

Consider the recent investigation of putting in a new tankless heater at one of our project houses by the EHT staff: Specifically, the residence in issue included a separate mother-in-law apartment in the basement that was using one of two separate tank-style heaters to accommodate the two distinct homes.

• In the end, we concluded that the tankless unit would not be an appropriate fit for the house after speaking with an electrical professional.
• The reason for this is because, while electric tankless systems conserve energy while the heating coils are not in use, when the heating coils are in operation, they require a significant amount of electrical power in brief bursts.
• Our electrical consultant informed us that the house in issue was already reaching its maximum 200-amp electric load capacity before the new tankless system was installed.
• “All right,” we said the electrician.
• He replied, “thousands,” and then on to complain about municipal permits, city inspectors, and other issues in the city of Philadelphia.
• The Electrical Supply of a House is being assessed Before purchasing a new electric tankless heater, homeowners should consult with an electrician to ensure that the unit will be a good fit with their home’s electrical supply.
• According to the amperage of a home’s electrical service, the number of appliances that may be used at the same time is determined.

It takes two 40-amp breakers to install the EcoSmart Eco-18 model, which has a pull of 75 amps.

Essentially, an electrical conduit is a pipe that enters a home either from an underground main electric line or from an above-ground service.

Although many conduits are undersized, a 2-inch pipe may be able to accommodate a 60-amp service, for instance.

The electrical capacity of a service wire that is visible can also be determined.

(Note: Do not touch any exposed wire while working on this project).

Look for a label on your electrical panel that displays the panel’s rating.

Additionally, the amperage rating on your primary breaker or fuse should provide a clue.

A word of caution: measuring the wires in one’s own circuit breaker panel is not recommended for the average homeowner.

Sometime the wire size may represent one thing, but the actual amperage flowing from the source may be quite another.

To establish the lowest amperage rating, your electrician should compare all of the information. Using the lowest figure, which represents your home’s electrical service capacity, you may determine which tankless electric water heater is most appropriate for your needs.

## What Size Breaker for Electric Tankless Water Heater?

Isn’t it frustrating and time-consuming when you buy a breaker and an appliance, only to discover that they don’t work together? It can be difficult and time-consuming to figure out what size circuit breaker to utilize for an Electric Tankless Water Heater (ETWH) at times. It’s also time-consuming because you’ll have to purchase a circuit breaker for each terminal/heating element you use. So, in order to determine the appropriate breaker size, you must first determine the wattage, voltage, and amps of your water heater.

## Picking the Perfect Breaker Size

Now, the most dependable and precise approach for determining the proper breaker size for a water heater is to consult the instructions that came with your electric tankless water heater. In addition, you can see the sort of wiring that it has, which is comparable to the amount of breakers that are required for the equipment in question. Is it a 3 x 50 (which implies that there are three heating elements protected by three 50-amp circuit breakers) or a 4 x 40 (which means that there are four 40-amp circuit breakers) circuit breaker?

Keep in mind that the more the number of breakers and the higher the amperage they provide, the greater the electrical current.

If, on the other hand, you are unable to locate the manufacturer’s instructions, you may always resort to the mathematician’s technique.

### 2. Use the Power formula

Make use of the power equation, P= I x V, from which we may get the following formula to determine the amp size: I= P x V (where I equals amps, P equals watts, and V equals Volts). Because the normal voltage for an ETWH is already 240 Volts, you’ll just need to determine the amount of power input or watts required by your device, which may be found on the device’s specifications sheet or on the water heater itself, to complete your installation. Following the collection of all of the necessary factors for a tankless water heater breaker size, you may proceed to the calculation.

• Consider the following scenario: a heating element requires 7600 watts from a 240-Volt circuit.
• Although it is possible to use the precise amperage as the breaker size, doing so is not recommended.
• If you don’t do this, you run the danger of having an accident since there will be no protection against a power surge.
• This safety measure is required because 100 percent continuous loads create heat that is potentially harmful enough to spark a fire at the circuit breaker’s wire connections.
• To get the breaker size, multiply 1.25, or 125 percent, by the rated amp of your device, which in this example is 31.7 amps, to obtain the breaker size.
• For example, for a safe maximum continuous load on our sample heating element, the breaker you should purchase is 40 amps.

Some water heaters have numerous heating elements, as I previously said, necessitating the use of multiple circuit breakers for each heating element. Take into consideration various heating components, as well as the main heating element.

## Electric Tankless Water Heater: How It Works

In addition to the electric water heater breaker size, you may be interested in learning more about how this machine operates, its advantages and disadvantages, and its total power. If you have an old tank water heater, you may already be familiar with the mechanics of a water heater. Tankless and traditional water heaters are not that dissimilar in terms of performance, but there is a significant difference in the amount of electricity they consume. In contrast to conventional heaters, which contain the hot water within as it boils, the ETWH uses electrical components to heat the water that is contained inside the pipelines.

• Different manufacturers provide extras and premium features in each ETWH that they produce under their own brand.
• It is straightforward.
• Once the flow is stopped, the heat elements also come to a halt in their functions.
• The wattage of the heater (which can range between 10 kW and 40 kW) can be found in the handbook.
• Many people opt for this type of heater because it provides them with the convenience of having an endless supply of hot water.
• On the other side, there are disadvantages such as the need for additional equipment, the high cost of maintenance, and the inconsistency of water temperatures.

Electric tankless water heater installation requirements include a large main breaker panel for safety reasons, as a result of the several circuit breakers supplying each heating element. So, before you go out and buy a whole new heating equipment, ask yourself: “Do I really need to change my panelboard?” Given the rapid advancement of technology in recent years, 100-amp panels are enough for powering major appliances such as dishwashers and air conditioners. The most recent ETWH available today is incapable of operating at so low an amp.

• Assume you have three breakers rated at 40-50 amps each, each of which is powering three heating components.
• 125 percent of the heater’s continuous load might be calculated to determine the size of your primary breaker panel if you do not know how to do so.
• It is important to note that electric tankless boilers can consume anywhere from 10,000 to 40,000 watts.
• Therefore: In this case, I=30,000W x 240VI = 125 Amps.
• It is important to note that a standard 200-amp breaker panel should not be able to manage more than 160 amps at a time.

To be safe, it’s important to talk with your reputable contractor and have him examine the total power input of your ETWH and other electrical equipment before making any decisions. After that, you’ll be able to determine the optimal panel size.

## Conclusion

When it comes to determining what size breaker to utilize for an electric tankless water heater, responsibility and meticulous calculations play a significant role. Before you install this heating device, you should pay close attention to the size of your fail-safe device or devices, which will protect your home from electrical and fire accidents in the event of an electrical or fire disaster. The best course of action is to consult with a licensed electrician to identify the most appropriate breaker amp size.

Last but not least, determine the continuous load by multiplying 125 percent by the final amperage received.

## Tankless Gas Water Heater Electrical Requirements

Water heaters that do not require a storage tank, whether gas or electric, are extremely efficient when compared to standard water heaters. While a gas tankless unit utilizes propane to heat water, several sections of the water heating system still rely on electricity to function correctly. So, what are the electrical requirements for a tankless natural gas water heater, exactly? Most tankless gas water heaters require a 120-volt circuit with a 15-ampere or 20-ampere rating to power the electric pilot light and control board, respectively.

Depending on whether you reside in an area with a 220 volt or a 110 volt power source, the electrical needs for your tankless gas water heater might differ significantly.

Voltage ratings are available in four different voltage ranges: 208V, 120V, 240V, and 277V.

## Electrical Requirements of a Tankless Gas Water Heater

National Electrical Code requires that tankless gas water heaters be equipped with a 15-20 ampere 120-volt electrical circuit that supplies power to the unit’s control board and ignition device. Because the control circuit is an independent load, the circuit ratings are determined by the setting of the circuit breaker. A propane tankless water heater is equipped with an electrical control circuit that guarantees that the appropriate amount of electricity is delivered to the control board. The control board measures the temperature of the water that is supplied into the tankless unit as well as the temperature of the water that exits the water heater and flows into the taps around the house.

When correctly powered in accordance with the NEC regulation, the control board is capable of regulating the amount of heat necessary to get water up to the appropriate temperature.

In the case of Rinnai, Takagi, EcoSmart or Rheem tankless natural gas water heaters, the manufacturer will have calculated and defined the circuit size before you installed your water heaters.

The devices are often sent with thorough installation instructions to assist you or your technician in completing the installation correctly.

## Electrical components in a tankless gas water heater

The majority of homeowners believe that a gas water heater will continue to operate in the event of a power loss. Despite the fact that the tankless unit does not utilize electricity as a fuel to heat the water, it may be dependent on some electric components in order to operate correctly. You’ll find the following electrical components in your tankless gas water heater:

### Electric control board

The electric control board of a tankless gas water heater is an integral component of the unit. The information and communication between all electrical components in a series circuit are relayed and monitored by electric control boards. This is what enables for proper operation to take place without interruption or malfunctioning of any kind. The electric control board functions similarly to the personal computer unit of the water heating system. It requires energy to operate the water heater, which is why your gas instantaneous water heater may not function properly if there is a power outage in your neighborhood.

The gas valve, burner, and water temperature are all controlled by this circuit board, to put it simply.

### Gas pilot light

In some types of any propane or natural gas hot water system, a gas pilot light is an inherent element of the gas safety mechanism, which is illuminated by the pilot light. The pilot light in your water heating system is a little flame that is maintained at all times. The electric control board is in charge of controlling the gas pilot light. When it is necessary to heat water, the pilot light is activated, which causes the burners to ignite and heat the water to the temperature specified by the control unit.

## Electrical Requirements for Different Brands

According on the type and manufacturer, the electrical requirements for tankless gas water heaters might differ significantly. According to the heating requirements of each home, the heating capacity of these devices varies significantly. The result is that circuit breaker installations, electrical wire gauges, and resistance will all differ significantly. Takagi, Rinnai, Stiebel Eltron, Mitsubishi, and Eemax are just a few of the well-known brands available in the United States. It is critical to double-check their installation guides to ensure that you meet all of the electrical standards and avoid any potential safety issues.

### Rinnai

Rinnai tankless water heaters require 120 volts alternating current at 60 hertz with a current of less than 3 amps. As a result, it can only be used in the United States, Canada, Mexico, and portions of South America, and it has backward compatibility going back as far as 50 cycles.

The tankless water heater must be connected to a 120-volt outlet and powered by 60Hz current. Tankless water heaters from Rinnai have a wide variety of electrical needs, from a 20 amp circuit breaker to the demand for multi-phase electricity.

### Takagi

Takagi tankless water heaters have electrical needs of 120 V alternating current 60 Hz and take less than 2 Amperes of power. The outlet must be connected to a dedicated circuit and should not consume more than 70% of the circuit’s total capacity, or the breaker would trip. When possible, use of a ground fault circuit interrupter (GFCI) outlet; however, if this is not practicable, an arc fault protection device (AFCD) that turns off electric current when it detects arcing inside the home’s wiring is needed by law.

Also recommended is having an electrical examination performed on your property prior to installing tankless gas water heater electrical requirements in order to detect any concerns that may occur as a result of its operation.

• National Electrical Code Style Manual
• Takagi: Instantaneous Water Heater Installation Manual and Owner’s Guide
• Thomas L. Harman, IAEI Magazine: “Go Tankless. “
• Takagi: Instantaneous Water Heater Installation Manual and Owner’s Guide And continue to soak in hot water

## Electrical Requirements – EcoSmart

It is important to ensure that your house has adequate electrical capacity for your selected model, or that you have made a note of any changes that may be necessary, prior to purchasing an EcoSmart electric tankless water heater. A licensed expert must install your system in order to assure your safety and verify that you are eligible for the limited lifetime warranty. Please see the table below for information on electrical needs.

Model Recommended Breaker Maximum Amperage @240V Recommended Household Electric Service Recommended Minimum Wire Gauge
ECO 36 4 x 40 Amps DP 150 Amps 300 Amps 4×8 AWG
ECO 27 3 x 40 Amps DP 112.5 Amps 200 Amps 3×8 AWG
ECO 24 3 x 40 Amps DP 100 Amps 200 Amps 3×8 AWG
ECO 18 2 x 40 Amps DP 75 Amps 150 Amps 2×8 AWG
ECO 11 1 x 60 Amps DP 57 Amps 125 Amps 1×6 AWG
ECO 8 1 x 40 Amps DP 33 Amps 100 Amps 1×8 AWG
POU 6 1 x 30 Amps 29 Amps 100 Amps 1×10 AWG
POU 3.5 1 x 30 Amps 29 Amps 100 Amps 1×10 AWG

## How Many Amps Does Water Heater Use?

Make sure your house has enough electrical capacity for your selected model before acquiring an EcoSmart electric tankless water heater, or that you have made a note of any changes that may be necessary before making your purchase. Your system must be installed by a certified expert in order to assure your safety and eligibility for the limited lifetime warranty. Regarding electrical needs, please see the table below:

• Heater type, fuel type, capacity, and energy efficiency are all important considerations.

It is critical for every homeowner to be aware of the quantity of amps required by their water heater. Making a decision on a water heater may be a difficult undertaking, especially with so many options available. In any case, after you have gained an understanding of the numerous possibilities discussed below, you will be able to make an educated selection.

## Heater Type: Tank or Tankless

It is possible to use a water heater in one of two ways: with a tank that holds water that is continually heated or with coils that heat water as needed. Tank heaters are often referred to as storage heaters or container heaters. These pieces of equipment are the oldest and most conventional types of equipment available. Tankless heaters are also referred to as on-demand heaters in some circles. These units have a more recent design. Storage water heaters, on average, consume less electricity than tankless water heaters.

Given the tankless heaters only operate when necessary, their overall power consumption may be reduced, depending on the amount of actual use they get.

### What Size Breaker for a 40-Gallon Electric Water Heater?

Among home container heaters, a 40-gallon tank is the most often seen size. As a result, if you are installing this size unit in an older home, it is likely that you will be replacing a unit of comparable size. An old unit will have to be removed and replaced with a new one if an installation decides to use an older unit. In most cases, there is no additional charge.

This size unit will often require a 30-amp circuit breaker, which is one of the most common sizes of circuit breakers found in residential buildings. Most homes will not require any form of electrical system update as a result of the installation of this type of gadget because of this.

### How Many Amps Does a Tankless Water Heater Use?

On average, an on-demand heater consumes 120 amps of electricity to operate, which is significantly greater than the consumption of typical heaters, which consume just 30 amps. Many older homes only have 100 to 200 amps of available power, necessitating the installation of a professional electrician to improve the electrical system. During this upgrade, an electrician may recommend that you have a subpanel of circuit breakers installed in your home in order to improve the overall amount of amperage that is available.

## Fuel Type: Electric or Gas

The type of fuel that your water heater burns has an impact on the quantity of electricity it requires to function properly. A water heater will often be powered by electricity or natural gas to operate.

### Electric Water Heaters

These sorts of units are less expensive to purchase than gas-powered units, but they are more expensive to operate. This is due to the fact that electricity is generally more expensive than natural gas on a per-unit basis. The energy consumption of an electric water heater is around \$42 per month on average. However, because it may be connected to your home’s electrical system rather than requiring the installation of a gas line, this sort of heater is typically less difficult to install.

### How Many Amps Does an Electric Water Heater Use?

An electric heater with a tank necessitates the installation of a 240-volt dedicated circuit with a 30-amp fuse. The fact that this type of equipment requires a dedicated circuit means that an electrical update for your home could be required. A 120-amp circuit breaker is required for a tankless electric unit. When installing this sort of gadget in an older home, the electrical system will need to be upgraded. When it comes to on-demand water heaters, this improvement represents still another additional price in terms of up-front fees.

### Gas Water Heaters

Heaters that run on gas are typically 25 to 50 percent more expensive than heaters that run on electricity, according to industry standards. However, because they are less expensive to operate, they are more likely to make up for the price difference over the long term. For the ordinary household, a gas water heater will cost around \$30 per month on average. Due to the fact that gas units must be connected to a gas line, there may be an additional cost associated with installing such a device for the first time.

### How Many Amps Does a Gas Water Heater Use?

It will take 30 amps of electricity to power a gas water heater with a tank, which normally does not necessitate any changes to the home’s electrical system–even in older homes with just a total of 100 or 200 amps of service. A tankless device that works on gas will necessitate the use of a 120-amp circuit breaker. Because of the high amperage of this type of breaker, many older homes will require electrical system upgrades in order to support this sort of device.

### Should You Change Your Heater’s Fuel Type?

Depending on who you ask, many people believe that if they currently have an electric water heater, it is difficult to switch to a gas one, or that the opposite is true. This isn’t always the case, of course. If you are interested in altering the sort of equipment you now have, all you need to do is consult with an expert. A large number of electricians and plumbers provide free consultations. Find a company in your neighborhood that performs this and just ask them to conduct an evaluation for you.

Some carriers may even be able to offer you with an estimate of the expenses over the phone, if you ask nicely. When considering whether or not to switch the fuel source for your water heater, ask yourself the following questions:

• Is the gasoline type you’re looking for available in your area? What will be the cost of the installation
• Will the installation necessitate the acquisition of a permit
• Will you be required to improve the overall amperage of your home? When you switch to this new gasoline type, how much will your monthly payment be?

Once you have answered the questions above, you will be able to determine whether or not changing the fuel type of your heater is worth the time, effort, and money required. Changing the fuel type of your heater may necessitate more effort and expense during the installation process, but it may be more cost effective in the long run.

## Capacity

It is only when you have hot water when you need it that a water heater is truly beneficial. Regardless of whether the unit has a tank or not, or whether it is powered by gas or electricity, if it is not the proper size for your household’s water needs, it will not function properly. It is also dependent on the capacity of your heater as to how much power it will demand from it. Storage water heaters, for example, come in a variety of tank sizes ranging from 20 to 80 gallons. The larger the tank, the greater the amount of energy required to heat the water.

1. You should increase the size of your water tank by 10 gallons for each new person that lives in your house.
2. Your electricity or natural gas utility bill will rise in direct proportion to the amount of power the device consumes at any one moment.
3. To put it another way, if you want to be able to take a shower while also doing laundry and running the dishwasher, you must add the flow rates of each of these machines together.
4. Using the Tankless Water Heater Sizing Diagram, you may determine which size heater will be most suitable for your needs.
5. It may seem enticing to get a unit with the highest capacity available, but doing so may demand more amps than your home is capable of providing.

## Energy Efficiency

According to studies, heating a home’s water accounts for around 18 percent of the overall energy consumed by the residence. The efficiency with which your heater utilizes energy will also have an impact on the number of amps the device consumes. Generally speaking, the more energy-efficient a heater is, the more amps it will require to operate. However, even if a more energy efficient heater may take more amperage to turn on, the unit will be in use for a shorter period of time, resulting in a reduction in total energy expenditures.

In the event that your unit is more than 10 years old, it may be time for you to consider upgrading to a more energy-efficient model.

However, because natural gas is often less expensive than electricity, the two units are typically equal in terms of cost.

Keep an eye out for the Energy Star badge while shopping for a new heater. This mark indicates that the device complies with the Energy Star requirements. These gadgets have a tendency to be more energy efficient, which results in their being more cost effective.

## Conclusion

Having access to hot water when you need it is no more a luxury, but rather a need in today’s day and age. As a result, you must locate a unit that is within your budget, both in terms of up-front fees and ongoing operating expenses. It is also critical to evaluate the total quantity of energy that your water heater will use from your home in order to verify that your electrical system is capable of handling the demand.