Question 23

The smallest size Type K copper tubing that can be used for a 90-foot piping system is 7/8 inch.

For a 90-foot piping system designed to carry gas, the smallest size of Type K copper tubing that meets the required flow rate and pressure drop specifications is 7/8 inch.

A) 0.5-psi piping system designed to carry 195 cubic feet per hour of gas with a total pressure drop of 1-inch water column

This option describes a system rather than a specific size of copper tubing. While it provides details about the pressure and flow requirements, it does not indicate a tubing size, making it irrelevant to the question.

B) 3/4 inch

While 3/4 inch tubing may be suitable for certain applications, it does not meet the flow requirements for a system carrying 195 cubic feet per hour over a distance of 90 feet with a specified pressure drop. Therefore, it is not the correct choice.

C) 7/8 inch

7/8 inch Type K copper tubing is the correct answer as it is the smallest size that can adequately handle the flow rate of 195 cubic feet per hour with a total pressure drop of 1-inch water column over a length of 90 feet, ensuring efficient gas distribution.

D) 1 inch

While 1 inch tubing would certainly accommodate the flow requirements, it exceeds the minimum size needed for the specified conditions. Thus, it is not the most efficient choice when a smaller size is sufficient.

E) 1 1/4 inches

1 1/4 inch tubing is larger than necessary for the given specifications. Although it would function correctly, it does not represent the smallest size which meets the requirements, making it an incorrect option.

Conclusion

In summary, 7/8 inch Type K copper tubing is the smallest size that fulfills the flow and pressure drop requirements for the specified 90-foot piping system. All other options either fail to provide a valid tubing size or exceed the minimum necessary, confirming that 7/8 inch is the most appropriate choice.