Journeyman Plumbers Exam Plumbing Fixtures and Appliances 3 — Questions and Answers
Question 1: Which appliance requires a dedicated GFCI-protected circuit AND a plumbing drain connection?
- Gas range
- Dishwasher
- Garbage disposal
- Clothes washer (Correct answer)
Correct answer: Clothes washer
A clothes washer requires both a dedicated electrical circuit (with GFCI in some locations) and a standpipe drain connection for proper installation.
Question 2: The minimum standpipe height for a clothes washer drain receptor above the trap weir is:
- 12 inches
- 18 inches
- 24 inches (Correct answer)
- 36 inches
Correct answer: 24 inches
The IPC requires a standpipe receptor for clothes washers to extend a minimum of 24 inches above the trap weir to prevent backflow.
Question 3: A water heater temperature and pressure (T&P) relief valve discharge pipe must terminate:
- Into the cold water supply line
- At a floor drain or within 6 inches of the floor (Correct answer)
- Directly outside the building
- Into the hot water outlet pipe
Correct answer: At a floor drain or within 6 inches of the floor
The T&P relief valve discharge must terminate at a safe point of discharge, typically within 6 inches of the floor or into a floor drain, to prevent scalding.
Question 4: What is the purpose of the air gap on a dishwasher drain connection?
- To reduce water hammer
- To prevent backflow of contaminated water into the dishwasher (Correct answer)
- To allow venting of drain gases
- To regulate drain flow rate
Correct answer: To prevent backflow of contaminated water into the dishwasher
The air gap provides a physical break in the drain line to prevent contaminated sink or disposal water from siphoning back into the dishwasher.
Question 5: A garbage disposal should be connected to the drain system using:
- A 1-1/4 inch trap and drain
- A 1-1/2 inch trap and drain minimum (Correct answer)
- A 2-inch trap and drain minimum
- A 3-inch trap and drain
Correct answer: A 1-1/2 inch trap and drain minimum
Garbage disposals require a minimum 1-1/2 inch trap and drain connection to handle the ground food waste without clogging.
Question 6: Which type of water heater uses a heat exchanger coil submerged in a storage tank supplied by a boiler?
- Tankless water heater
- Heat pump water heater
- Indirect-fired water heater (Correct answer)
- Power-vent water heater
Correct answer: Indirect-fired water heater
An indirect-fired water heater uses a boiler to heat water circulated through a heat exchanger coil inside the storage tank rather than burning fuel directly.
Question 7: When a lavatory is installed in a wheelchair-accessible restroom, the drain trap and supply pipes must be:
- Concealed inside the wall with access panels
- Insulated to protect users from contact burns (Correct answer)
- Raised to the standard 21-inch rough-in height
- Installed with chrome-plated exposed pipes only
Correct answer: Insulated to protect users from contact burns
ADA-compliant accessible lavatories require insulated or covered drain and supply pipes to prevent burns to users with limited sensation who may contact the pipes.
Journeyman Plumbers Exam Plumbing Fixtures and Appliances 3
Which appliance requires a dedicated GFCI-protected circuit AND a plumbing drain connection?