If a single-phase line-voltage electric heater is rated at 1,800 W, what is its heat output?

To determine the heat output of an electric heater rated at 1,800 watts, it's important to convert the electrical power measured in watts to heat output measured in British thermal units per hour (Btu/hr). The conversion factor between watts and Btu/hr is critical for this calculation.

1 watt is equivalent to approximately 3.412 Btu/hr. To find the heat output in Btu/hr, you multiply the power (in watts) by this conversion factor:

1,800 W × 3.412 Btu/hr/W = 6,143.4 Btu/hr.

This calculation shows that an electric heater rated at 1,800 watts will generate a heat output of 6,143.4 Btu/hr. This understanding of conversion from watts to Btu/hr is essential in HVACR applications as it helps to assess the heating capacity of electrical heating systems effectively.