It looks like you're using an Ad Blocker.
Please white-list or disable AboveTopSecret.com in your ad-blocking tool.
Some features of ATS will be disabled while you continue to use an ad-blocker.
Wire a hot water heater with wire that's sized to accommodate the heater's current requirement. 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. Some large heaters draw up to 50 amps, requiring 6-gauge wire.
A water heater of this type is required to be considered a continuous load meaning that the branch circuit needs to be calculated at 125% of the heater's rated ampacity. 4500/240 = 18.75 amps, will work on a 20 amp OCPD but, 18.75*125% = 23.4 amps, requires a 25 or 30 amp circuit