Water Heater Wire Size

Multiply the current rating of the water heater with 125 now in order to choose an electric breaker multiply the current draw of the water heater with 125 per cent in order to determine the size of the breaker you will need.

Water heater wire size. Below we ve highlighted what size water heater you would need in our example of 6 5 gpm at a 63 f temperature rise. Simply locate the appropriate water heater sizes on ecomfort using your information. Once you have your total flow rate and the required temperature rise you can find the right size tankless water heater for your home. Understanding water heater wiring.

Electric water heaters require a 240 volt dedicated circuit which serves only the water heater and no other appliances or devices. You have stated that the calculated amperage load for 4500watt at 240volts is 18 75amps however nec article 422 13 states that the minimum circuit rating for a water heater must be 125 of the rated load so this 4500watt load requires a minimum circuit of 23 44 amps at 240volts. Some large heaters draw up to 50 amps requiring 6 gauge wire. The first hour rating is the number of gallons of hot water the heater can supply per hour starting with a tank full of hot water.

In the above example we would require a 15 6 amp circuit breaker for our us readers. The circuit cable wiring includes two insulated wires designated as line 1 line 2 and the ground conductor. The the typical circuit is a 30 amp 240 volt dedicated circuit. For example a 20 amp hot water heater needs 12 gauge wire a 25 amp hot water heater requires 10 gauge wire and a 30 to 40 amp hot water heater requires 8 gauge wire.

To properly size a storage water heater for your home including a heat pump water heater with a tank use the water heater s first hour rating. The circuit wiring typically includes a 30 amp double pole breaker and 10 2 non metallic nm or mc cable. Wiring a 4000 watt electric water heater for a home. Wire a hot water heater with wire that s sized to accommodate the heater s current requirement.

An conventional residential 240 volt electric water requires a dedicated circuit.