Massachusetts Plumbers Journeyman Practice Exam

Which fitting could be legally installed where the branch is larger than the main piping?

1. 3x2 reducing elbow

2. 4x3 closet bend

3. 2-inch coupling

4. 1/2-inch straight coupling

The correct answer is: 4x3 closet bend

The correct choice, which allows for installation where the branch piping is larger than the main piping, is a 4x3 closet bend. This type of fitting is designed specifically to connect larger branch lines to a main line while ensuring proper flow and functionality in plumbing systems. Using a closet bend allows for the necessary transition from a larger pipe diameter to a smaller one, facilitating effective drainage and venting in a plumbing setup. This practice complies with plumbing code regulations that dictate how different sized pipes can be joined in order to maintain proper system performance and prevent issues such as clogging or pressure problems. In contrast, options like the 3x2 reducing elbow, 2-inch coupling, and 1/2-inch straight coupling do not accommodate such configurations and are generally suitable for different size transitions or connections. The reducing elbow is specifically meant for a larger pipe connecting to a smaller one, while couplings typically serve to join pipes of the same diameter rather than accommodate scenarios where the branch is larger.