What is the size of the gas feed line down to the boiler?

In this scenario, the correct answer indicated is that the size of the gas feed line down to the boiler is not 6 inches. This suggests that the gas feed line connected to the boiler is a size smaller than 6 inches, as anything larger would not be appropriate based on standard practices for gas line sizing.

When determining the appropriate size for a gas feed line, various factors are considered, including the type of fuel, the distance to be covered, and the demand of the appliance. Typically, the feed line is chosen based on the BTU (British Thermal Units) required by the boiler. A line size of 6 inches would be excessive for most residential and even many commercial applications where smaller gas lines are sufficient and meet the equipment requirements adequately.

Thus, the selection of a gas feed line that is not 6 inches aligns with industry norms, indicating that the size of the feed line should accommodate the operational needs of the boiler without being unnecessarily large, which could increase installation costs and complicate the system design.