Journeyman Plumber ExamGas PipingEasy
A plumber is sizing a gas line for a new commercial kitchen. The kitchen includes a range with an input rating of 150,000 BTU/hr, an oven with 100,000 BTU/hr, and a water heater with 75,000 BTU/hr. All appliances are located approximately 75 feet from the gas meter. Assuming a supply pressure of 7 inches of water column and a maximum pressure drop of 0.5 inches of water column, what is the total demand for the gas line?
- A375,000 BTU/hr
- B250,000 BTU/hr
- C325,000 BTU/hr
- D225,000 BTU/hr
Show answer & explanationAnswer & explanation
Correct answer: C. 325,000 BTU/hr
The total demand for the gas line is the sum of the input ratings of all connected appliances. (150,000 + 100,000 + 75,000 = 325,000 BTU/hr).
Why the other options are wrong
- A. Incorrect sum of appliance ratings.
- B. Incorrect sum of appliance ratings.
- D. Incorrect sum of appliance ratings.
Total Gas Demand
The cumulative BTU/hr rating of all gas-fired appliances connected to a specific segment of gas piping, used for sizing purposes.
- Calculated by summing individual appliance ratings.
- Determines the required flow rate of gas.
- Essential for accurate pipe sizing to prevent pressure drops.
Memory trick: To size a gas pipe, you need the TOTAL HEAT, LENGTH, and PRESSURE DROP.