Electric tankless heaters only utilize electricity to heat water. As we all know, heating water is a difficult chore. As a result, electric tankless water heaters demand a high current or amps.
How many amps does a tankless water heater use? The wattage of an electric water heater is determined by its amount of watts, not by its amperage. The amperage is vital for ensuring that your current electrical system is not overburdened. An electric water heater’s standard voltage is 240V, and its specific power usage is 4500 Watts.
Tankless heaters can draw between 42 and 167 amps. Continue reading to learn more about the current consumption of water heaters.
How Much Amps Does A Standard Water Heater Use?
An on-demand heater typically takes 120 amps to operate. This is much more than the older machines, which only require 30 amps to operate.
If you live in an older home, your available amperage is only 100-200. This may necessitate an update to your electrical system by a professional electrician, which may include adding a subpanel of circuit breakers to boost the total amps available. The kind and fuel requirements of the heater, as well as its capacity, are essential factors that influence the amount of amperage consumed by water heaters.
| Heater Size KW | Current In Amps |
| 10 | 42 |
| 20 | 83 |
| 21 | 88 |
| 22 | 92 |
| 23 | 96 |
| 28 | 117 |
| 29 | 121 |
| 30 | 125 |
| 31 | 129 |
| 32 | 133 |
| 33 | 138 |
| 39 | 163 |
| 40 | 167 |
Also, Read: Does A Tankless Water Heater Need An Expansion Tank.
Tankless Water Heater Power Requirements.
Tankless water heaters that run on gas or electricity are far more energy-efficient than traditional water heaters. Even though a gas tankless unit uses propane, the rest of the water heating system is still powered by electricity.
A 15- or 20-ampere 120-volt circuit is typically required to operate the electric pilot light and control panel on tankless gas water heaters. The National Electrical Code states that these sorts of water heaters may only be protected at a maximum amperage of 150 and are not allowed to have courses above 120 amperes.
Your tankless gas water heater will use varying amounts of electricity depending on where you reside. This is because some locations have access to 220 volts while others only have 110 volts. Therefore, the wattage of the device determines how much voltage the circuit requires. This typically runs between 208V and 277V.
Also, Read: How To Use the Rinnai Tankless Water Heater Priority Button?
How To Determine the Amp Use Of A Tankless Water Heater?
Water is heated using electricity by electric tankless heaters. Since heating water consumes a lot of resources, these tankless water heaters require a significant flow of electric current or amps.
Two significant factors that affect how many amps a tankless water heater needs are known to us:
Watts are used to quantifying overall power. Electric water heaters are typically the most powerful. For instance, a tankless electric water heater can be powered by anything from 10 kW to 40,000W.
A 240-volt circuit is necessary for the proper operation of all-electric tankless water heaters. The current can be calculated using the electric power equation (P = IV) as follows:
P = I x V.
What Is the Gas Tankless Water Heater’s Power Consumption?
A 15-ampere or 20-ampere 120-volt connection is required for all tankless gas water heaters in order to power the control board and electric pilot light. Instantaneous water heaters are required to have circuits with a maximum amperage of 120 amps and overload protection with a maximum amperage of 150 amps, according to the National Electrical Code.
How Much Power Do Electric Tankless Water Heaters Need?
When in use, a typical tankless water heater draws 120 amps. If you live in an older house, a professional electrician may be required to repair your infrastructure and boost the amperage available on your property.
Tankless water heaters can gradually cut your monthly electricity expenses since they are more energy-efficient ways to heat water as needed. In comparison, a typical tank water heater operates with less energy. Before you make a purchase, a qualified electrician can verify whether your house is suitable for a tankless water heater.
What Size Breaker Do I Need For A 40-gallon Water Heater?
The usual 30- or 40-gallon home water heater uses roughly 4500 watts and is powered by a 30-A breaker if I’m not mistaken.
What Size Breaker Do I Need For A 4500-WATT Water Heater?
A fully resistive load of 5,000 watts at 240 volts equals 23 amps; the breaker has a 30 amp rating, and the wire is 10 AWG.
The draw in your example is 18.75 amps if the elements are rated for 4500 watts; permanent draw loads ought to be constructed at 80% of breaker capacity. As a result, a 20-amp breaker can only handle 16 amps.
For a 7500-watt Heater, What Size Breaker Do I Need?
A 40 amp breaker is required because 750 watts multiplied by 240 volts results in 31 amps of current.
Conclusion.
Finally, it is crucial to understand the electrical needs of a tankless water heater in order for it to function efficiently and safely. A tankless water heater’s amp consumption varies depending on its size, model, and your home’s electrical needs. Consult a licensed electrician to confirm that your electrical system can support the amp load of the tankless water heater you intend to install. This allows you to enjoy limitless hot water while maintaining the safety and effectiveness of your home’s electrical infrastructure.
FAQ.
How many amps are required by a tankless water heater?
A 15-ampere or 20-ampere 120-volt connection is required for all tankless gas water heaters in order to power the control board and electric pilot light. Instantaneous water heaters are required to have circuits with a maximum amperage of 120 amps and overload protection with a maximum amperage of 150 amps, according to the National Electrical Code.
A 240V water heater uses how many amps?
At 240 volts, the typical electric water heater amperage is 18.75 amps. The average power consumption of an electric heater is 4500 watts, though this varies depending on the model.
Can a 200 amp service power a tankless water heater?
150a at 240v is equal to 36 kW. That is approximately the greatest continuous load that a 200a supply can give when water heaters are taken into account (160a). Since I wouldn’t place this on a 200a panel that provides anything else, the shop panel is the worst of the two possibilities.
How much energy does a tankless water heater consume?
It is necessary to connect the heater to a different 120- or 240-volt circuit. Both voltages require an 8-gauge wire, which needs to be armored in the exposed space under the sink. If the manufacturer’s instructions call for a bigger cable, you must utilize it according to the National Electrical Code.
