What is the size of the domestic cold water supply noted for the scenario associated with the entry labeled 'question 6'?

What is the size of the domestic cold water supply noted for the scenario associated with the entry labeled 'question 6'?

• A. 1-1/4 inches
• B. 3/4 inch
• C. 1 inch
• D. 1-1/2 inches

Answer: (B)

In domestic plumbing, the cold-water supply feeding a typical residential appliance (like a water heater) uses a 3/4 inch connection. This size is standard because it provides enough flow to meet normal hot-water demand without carrying the extra cost and potential pressure drop of a larger line. A 1/2 inch line is usually too small for a main cold inlet to a heater and can limit flow, while sizes like 1 inch or larger are generally used for main service or multi-fixture runs, not just a single heater. Therefore, 3/4 inch is the appropriate choice for the domestic cold water supply in this scenario.

In domestic plumbing, the cold-water supply feeding a typical residential appliance (like a water heater) uses a 3/4 inch connection. This size is standard because it provides enough flow to meet normal hot-water demand without carrying the extra cost and potential pressure drop of a larger line. A 1/2 inch line is usually too small for a main cold inlet to a heater and can limit flow, while sizes like 1 inch or larger are generally used for main service or multi-fixture runs, not just a single heater. Therefore, 3/4 inch is the appropriate choice for the domestic cold water supply in this scenario.