Case Analysis & Practical Application Flashcards

You are asked to install a ceiling fan where only a standard light fixture box exists. The box is rated for 35 lbs. The fan weighs 28 lbs. What is the correct action?

Answer: Replace the box with a fan-rated brace bar assembly before installation

Ceiling fans require fan-rated boxes because of dynamic load and vibration; a standard light box rated for weight alone is not approved for fan use.

A customer reports intermittent flickering of lights throughout the house, not just on one circuit. What is the most likely cause?

Answer: A loose neutral connection at the main panel or utility connection

Whole-house intermittent flickering typically points to a loose main neutral, which can cause voltage fluctuations across all circuits.

While caulking the joint between a bathtub and tile wall, you notice the existing caulk has black mold underneath. What is the correct remediation sequence?

Answer: Remove all old caulk, treat with mold-killing solution, allow to fully dry, then re-caulk

Removing all old caulk, killing existing mold spores, and ensuring complete dryness before re-caulking prevents mold from growing under the new application.

A homeowner wants to convert a 3-prong dryer outlet (NEMA 10-30) to a 4-prong outlet (NEMA 14-30) for a new dryer. What does this conversion require?

Answer: Running a new 4-wire cable (two hots, neutral, and ground) from the panel to the outlet

A NEMA 14-30 requires a separate equipment ground wire; the old 3-wire circuit lacks this, so new 4-wire cable must be run from the panel.

You discover that a toilet is rocking slightly and has a soft floor around the base. What is the most important first step?

Answer: Turn off the water supply and inspect for subfloor damage before any other repair

A soft floor around a rocking toilet suggests subfloor water damage that must be assessed before making any repairs, since the scope of work may be much larger.

A sliding patio door is difficult to open and close. After cleaning the track, it still drags. What is the next most likely fix?

Answer: Adjust or replace the door's roller assemblies at the bottom of the door panel

Worn or damaged roller assemblies are the most common cause of a hard-to-slide patio door after the track has been cleaned.

You are patching a 6-inch hole in drywall. Which method provides the most structurally sound repair?

Answer: Cut a clean square, install backing clips or a backer board, then install a cut patch piece

For holes larger than 4–5 inches, a California patch or backer-clip method with a properly fitted drywall piece provides solid backing and a flush, durable repair.