How many amps does an electric heater draw?

12.5 Amps Click to see full answer. Just so, how many amps does an electric blanket use?12 volt electric blankets will draw about 4.5 amps. Over 10 hours that’s 45 amps drawn from the battery.Beside above, what size breaker do I need for a 1500 watt heater? A 1500-watt heater on a 120-volt circuit thus needs a breaker of 15.6 amps. Because a 15-amp breaker would be too small, you need a breaker with the next highest rating, which is 20 amps. Include the current draw of any other devices on the circuit when calculating the breaker size. Also Know, how many amps does a 1000 watt heater draw? Equivalent Watts and Amps at 120V AC Power Current Voltage 900 Watts 7.5 Amps 120 Volts 1000 Watts 8.333 Amps 120 Volts 1100 Watts 9.167 Amps 120 Volts 1200 Watts 10 Amps 120 Volts How many amps does a 3000 watt heater draw?I knew that 3000 watts with the feeble 120 volts used here in the US would call for (3000 W /120 V) = 25 amps which is way more than our house was designed for. (The rest of the world uses 240 volts which results in a mere 12.5 amps which is quite reasonable.)