Case Analysis & Practical Application Flashcards

A homeowner reports that a GFCI outlet in their bathroom keeps tripping immediately after being reset. What is the most likely cause?

Answer: There is a ground fault or moisture in the circuit downstream of the GFCI

A GFCI that trips immediately after reset typically indicates a ground fault or moisture downstream in the protected circuit.

You are repairing a wooden deck and find that several joists have soft, spongy areas near the ledger board. What should you do first?

Answer: Replace the ledger board flashing to stop ongoing moisture intrusion before any structural repair

Addressing the source of moisture (improper flashing at the ledger board) must come before structural repairs, or the new material will rot as well.

A customer asks you to hang a 200-lb mirror on a plaster wall. Your stud finder cannot locate studs reliably. What is the best approach?

Answer: Mount a backing board across multiple studs and attach the mirror to the board

For very heavy loads on plaster, a backing board spanning multiple studs distributes weight safely and provides reliable anchoring.

While snaking a clogged kitchen drain, you encounter solid resistance about 20 feet in that the snake cannot break through. What does this most likely indicate?

Answer: A collapsed or offset pipe section requiring camera inspection

Solid immovable resistance at a specific distance often indicates a collapsed or severely offset pipe that requires video inspection before further action.

A customer complains that their forced-air furnace runs continuously but the house never reaches the set temperature in winter. After confirming the thermostat is accurate, what should you check next?

Answer: Inspect and replace the furnace filter, then check for duct leaks

A clogged filter or significant duct leakage are the most common causes of a furnace running constantly without meeting the setpoint.

You notice that a newly installed exterior door has a consistent 1/4-inch gap at the top corner on the latch side. What adjustment should you make?

Answer: Adjust the top hinge by adding a shim to move the door closer to the frame on the latch side

A gap at the top latch-side corner means the door is leaning away there; shimming the top hinge pivots the top of the door toward the frame.

A homeowner has a slow-draining bathroom sink. After removing and cleaning the pop-up assembly stopper, the drain is still slow. What is the next logical step?

Answer: Use a hand auger or drain snake to clear the P-trap and branch drain

After confirming the stopper is clear, the blockage is likely in the P-trap or branch drain and should be mechanically cleared with an auger.