16 pages

Water Heater Breaker and Wire Size by Kilowatts

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Water Heater Breaker and Wire Size by Kilowatts: 16 pages. NEC 422.13 makes a storage water heater a continuous load, so the circuit is sized at 125 percent of nameplate. These pages apply that rule and the ampacity tables to every rating.

2.5 kW at 240 V A 2.5 kW water heater at 240 volts draws 10.4 amps. As a continuous load that becomes 13 amps of design load, needing a 15 A break
3.5 kW at 240 V A 3.5 kW water heater at 240 volts draws 14.6 amps. As a continuous load that becomes 18.2 amps of design load, needing a 20 A bre
4.5 kW at 240 V A 4.5 kW water heater at 240 volts draws 18.8 amps. As a continuous load that becomes 23.4 amps of design load, needing a 25 A bre
5.5 kW at 240 V A 5.5 kW water heater at 240 volts draws 22.9 amps. As a continuous load that becomes 28.6 amps of design load, needing a 30 A bre
6.5 kW at 240 V A 6.5 kW water heater at 240 volts draws 27.1 amps. As a continuous load that becomes 33.9 amps of design load, needing a 35 A bre
7.2 kW at 240 V A 7.2 kW water heater at 240 volts draws 30 amps. As a continuous load that becomes 37.5 amps of design load, needing a 40 A break
9 kW at 240 V A 9 kW water heater at 240 volts draws 37.5 amps. As a continuous load that becomes 46.9 amps of design load, needing a 50 A break
11 kW at 240 V A 11 kW water heater at 240 volts draws 45.8 amps. As a continuous load that becomes 57.3 amps of design load, needing a 60 A brea
12 kW at 240 V A 12 kW water heater at 240 volts draws 50 amps. As a continuous load that becomes 62.5 amps of design load, needing a 70 A breake
13 kW at 240 V A 13 kW water heater at 240 volts draws 54.2 amps. As a continuous load that becomes 67.7 amps of design load, needing a 70 A brea
18 kW at 240 V A 18 kW water heater at 240 volts draws 75 amps. As a continuous load that becomes 93.8 amps of design load, needing 2 circuits of
19.2 kW at 240 V A 19.2 kW water heater at 240 volts draws 80 amps. As a continuous load that becomes 100 amps of design load, needing 2 circuits o
24 kW at 240 V A 24 kW water heater at 240 volts draws 100 amps. As a continuous load that becomes 125 amps of design load, needing 3 circuits of
27 kW at 240 V A 27 kW water heater at 240 volts draws 112.5 amps. As a continuous load that becomes 140.6 amps of design load, needing 3 circuit
28.8 kW at 240 V A 28.8 kW water heater at 240 volts draws 120 amps. As a continuous load that becomes 150 amps of design load, needing 3 circuits
36 kW at 240 V A 36 kW water heater at 240 volts draws 150 amps. As a continuous load that becomes 187.5 amps of design load, needing 4 circuits