Recreational Vehicle (RV) Technician Practice Test

With two 20-pound cylinders, how long will a 30,000 BTU appliance run continuously at 60 degrees Fahrenheit?

1. 15 hours

2. 20 hours

3. 25 hours

4. 29 hours

The correct answer is: 29 hours

To determine how long a 30,000 BTU appliance will run continuously with two 20-pound cylinders at a temperature of 60 degrees Fahrenheit, it's essential to understand the relationship between the size of the propane supply, the energy output of the appliance, and the energy content of propane. Each pound of propane contains approximately 21,600 BTUs of energy. Therefore, one 20-pound propane cylinder contains about 432,000 BTUs (20 pounds x 21,600 BTUs/pound). With two 20-pound cylinders, the total energy available is 864,000 BTUs (2 x 432,000 BTUs). To find out how many hours the appliance can run, divide the total available BTUs by the appliance's BTU per hour rating. Calculating this gives: 864,000 BTUs ÷ 30,000 BTUs/hour = 28.8 hours. This calculation indicates that the appliance can run for approximately 29 hours. Hence, the correct answer reflects an understanding of energy content in propane and the power requirements of the appliance, leading to the conclusion that, at a temperature of 60 degrees Fahrenheit, the two cylinders can sustain the 30,000 BTU appliance for around