Plumber Pipe Installation & Repair Flashcards

When installing copper pipe with soldered joints, what is the minimum distance a solder joint must be from a previously made joint to prevent overheating?

Answer: 4 inches

A minimum of 4 inches between solder joints prevents heat transfer from remelting previously made joints.

Which type of pipe is best suited for underground water service lines due to its flexibility and corrosion resistance?

Answer: Type K copper

Type K copper has the thickest wall of all copper types and is rated for underground and exterior water service applications.

A homeowner reports banging noises when shutting off faucets quickly. What is the most likely cause?

Answer: Water hammer

Water hammer occurs when fast-closing valves abruptly stop water flow, creating a pressure shockwave that causes pipes to bang.

What is the correct slope for horizontal drainage pipe to ensure proper flow without solids settling?

Answer: 1/4 inch per foot

A slope of 1/4 inch per foot provides adequate velocity to carry solids through horizontal drainage pipes.

When making a repair to a leaking galvanized steel pipe, which fitting allows you to remove a section of pipe without turning the entire run?

Answer: Union

A union consists of three pieces that allow pipe sections to be disconnected and reconnected without rotating the entire pipe run.

What type of pipe support should be used when running copper water supply lines through holes in wood framing to prevent electrolytic corrosion?

Answer: Plastic-lined or dielectric hangers

Plastic-lined or dielectric hangers prevent direct metal-to-metal contact that can cause galvanic corrosion between dissimilar metals.

Which repair method is appropriate for a pinhole leak in a copper pipe in an accessible location when a full section replacement is not feasible immediately?

Answer: Apply a pipe repair clamp

A pipe repair clamp provides a reliable temporary fix by compressing a rubber gasket over the leak using a metal sleeve.