Get a new water tank? Wondering the wire size for electric hot water? Let our experience help you.
In total a standard hot water tank requires a wire size of 12 gauge AWG. This wire is rated for up to 20 amps of current. This would apply to most domestic hot water tanks of 38 US gallons with 3000 watt elements. It should be noted on the nameplate data on the side of the tank.
Not all tanks are the same size or wattage so we have made up a handy chart.
|Gallons US||Voltage||Amps||Wire size|
Wire Size For Hot Water Tank
Above is a chart telling you basic wire size of the most common domestic hot water tanks. For tanks smaller than 38 US gallons. We recommend to use the same minimum wire size of 12 gauge awg. Pay attention to the voltage of the smaller tanks.
Some of them can be 110 volt instead of 220 or 240. If you hook them up wrong it will blow up the elements. Always remember to make sure the tank is full of water before turning it on. When in doubt be sure to contact your local pro.
What wire do I use for an electric water heater?
Wire size for electrical service is determined by the maximum amperage. This 12 gauge wire is rated for up to 20 amps, which is adequate for most electric water heaters.
Make sure you have enough wire
It may be tempting to use a smaller wire size but this will result in more voltage drop and wasted energy. A larger wire size will also provide better durability under heavy load conditions.
A new tank requires at least 10 gauge copper wire while an old tank requires 8 gauge copper wire or heavier. Consult with your local building codes or check out our blog post on residential wiring requirements.
What wire do I use for a 220 water heater?
220 volt water heaters require a wire size of 12 gauge AWG. This wire is rated for up to 16 amps of current.
This should be noted on the nameplate data on the side of the tank.
It’s important to examine your hot water heater’s voltage before selecting a wire that is too small or too large. Using a wire that doesn’t match your voltage will result in damage, and may even cause a fire!
If you have any other questions about wiring for your water heater, please contact us!
What size wire do I need for a 4500 watt water heater?
A 4500 watt water heater would require a wire size of 10 gauge AWG. This wire is rated for up to 30 amps of current.
Not all tanks are the same size or wattage.
How many wires does a water heater need?
How many wires does a water heater need? That is a question we get often and the answer to that question is: 120 volt water heater require 2 wire. 240 volt water heaters require 12/2 wire
Three phase commercial water heaters require 3 wire.
All water heaters come with different wattage, gallon size and length. With this in mind you will need to know the following before installing your new tank:
-The type of water heater (electric or gas)
-The wattage or gallons needed for your hot water needs
-The length of the element wire needed to complete installation
Does an electric water heater use 110 or 220?
You should always refer to the nameplate on the side of the tank. There you will find the wattage and voltage as well as the total amps. Wire size for electric hot water. Do not hook up a 110 volt tank to 240.
Does hot water heater wire have to be in conduit?
In some cases yes. For wood construction homes Romex wire is sufficient. Anywhere the wire drops below 1.5 meters is must be protected from mechanical injury. On commercial project the wire is usually run in BX cable, tech cable or pvc conduit.
Can I run a 240V water heater on 120V?
Although the 120V hot water heater is a much cheaper purchase it can’t be wired to be compatible with a 240V circuit. This would require an electrician to install a 240V 15 amp breaker and wire a 240V 20 amp hardwire.
This type of conversion would require additional power usage as the voltage is increased. For example, a 3000 watt element on 120V will use about 24 amps. When converted to 240V, that same 3000 watt element now draws about 12 amps. If you supply a 120 volt element 240 volts it will glow red until it blows up. You must have the proper element for the application.
Can I use a 40 amp breaker for water heater?
If you have a tank that is rated for 20 amps, then a 40 amp breaker will not be sufficient. Keep in mind that these breakers are for the circuit that powers the tank and it should not be used to power other electrical loads.
A 20 amp circuit can handle a water heater with a 20 amp element, but not a 40 amp element.
Can I plug a hot water heater into an extension cord?
It is not recommended to plug a hot water heater into an extension cord. Extension cords are made for temporary use and not designed to carry the amount of electricity that may be needed by your hot water heater.
Do electric water heaters plug in?
Many electric water heaters plug in and can be placed near an outlet. Some hot water tank models, like the EcoPower Tankless Water Heater, do not need to be plugged in and can instead use a natural gas line. Some oil hot water tanks do plug into a standard 120 volt 15 amp outlet.
What size wire do I need for a 5500 watt water heater?
If your tank is rated for 5000 watts you would need a 8 gauge wire. Your tank will also be labeled on the side with its specifications. Beware, not all tanks are the same size or wattage.
It is important to note that there are two wires that are used in a water heater. The metal element wire and the thermostat wire. It is important to know that if using an electric water heater it is preferable to have these two wires separated so as not to overload the circuit breaker when it comes time to turn off power to the unit.
How many amps does a 120v water heater use?
Electric hot water tanks require a wire size of 12 gauge AWG. This wire is rated for up to 20 amps of current.
Most 120 volt electric water heater use a maximum of 15 amps 120 volt. 12.5 amps of this would be to power the element of 1500 watts.
What size breaker do I need for a 120v water heater?
This can be a difficult question to answer. The breaker size is dependent on the water heater’s wattage and certain other factors such as whether or not you have a 240v service.
If you’re unsure of the appropriate breaker size, call an electrical contractor.
Generally though 120 volt hot water heater require a 15 amp single pole breaker.
Can I run Romex to water heater?
Yes we can in any type of wood construction dwelling of building. Just make sure it is protected below 1.5 meters.
If the water heater requires more than 20 amps of current, then you would need to use a wire size of 10 gauge AWG.
As a safety note, please make sure your hot water heater is equipped with a GFCI breaker before running any electrical accessories to it.
Which breaker is for hot water heater?
If you’re not sure which breaker is for your hot water heater, the best thing to do is to turn off your circuit breaker and test a few of the breakers. If it’s not the breaker that you turned off, turn it back on and try another breaker.
For example, if you have a GFCI outlet in your kitchen, go to the circuit breaker panel in there and turn off that one. Then try flipping a few of the breakers that are still on.
If none of them work, then you know that your hot water heater is on a different circuit from the rest of your house. It might be on its own breaker or it could be on a separate meter from your house.
We hoped this article helped you understand wire size for electric hot water.