How much heat will a radiator rated at 1 EDR emit if it is supplied with steam at 1 psig?

A radiator rated at 1 Equivalent Direct Radiation (EDR) is designed to emit a consistent amount of heat based on the pressure of the steam supplied. When steam is supplied at 1 psig, the standard expectation is that it will produce approximately 240 BTU per hour per EDR. This value is derived from established heating and steam systems calculations, where 1 EDR generally corresponds to a heat output of 240 BTU/hr when operating under normal conditions at this specific pressure.

The choice of 240 BTU/hr as the correct answer aligns with conventional heating design standards that specify the thermal output of radiators based on their EDR ratings. Understanding this concept is crucial for determining the efficiency of heating systems and ensuring that spaces receive adequate warmth based on the steam pressure and radiator specifications.