Plumbing & HVAC Systems Flashcards
7 cards from real INTERNACHI practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Plumbing & HVAC Systems flashcards as text
When should a home inspector recommend testing a sump pump during an inspection?
Answer: By pouring water into the pit to verify the float switch activates the pump
Pouring water into the sump pit is the standard method to verify the float switch activates and the pump discharges water properly without waiting for rain.
What does a home inspector look for when evaluating a gas appliance's combustion air supply?
Answer: Whether adequate air openings exist to support complete combustion
Combustion appliances require sufficient air supply to burn fuel completely; inadequate combustion air leads to carbon monoxide production and flame rollout.
Which type of drain trap is prohibited by most plumbing codes because it loses its water seal easily?
Answer: S-trap
S-traps are prohibited because self-siphoning action caused by rapid drainage easily pulls the water seal out, allowing sewer gases to enter the building.
An inspector observes black ABS drain pipe that has been repaired with white PVC pipe and a standard coupling. What is the issue?
Answer: ABS and PVC require a special transition cement, not a standard coupling
ABS and PVC have different chemical compositions and require a special transition or all-purpose cement to bond; standard ABS or PVC cement will not create a lasting joint between them.
What is the typical temperature range at which a residential water heater thermostat should be set to balance scalding prevention and Legionella control?
Answer: 120–140°F
The recommended range is 120–140°F; 120°F minimizes scalding risk for most households, while 140°F is advised where Legionella is a concern — with an anti-scald mixing valve at fixtures.
Which HVAC component is responsible for moving refrigerant through the system by raising its pressure and temperature?
Answer: Compressor
The compressor is the heart of the refrigeration cycle, compressing low-pressure refrigerant vapor into high-pressure, high-temperature vapor for heat rejection at the condenser.
A home inspector finds that flexible gas connectors behind a gas range pass through the cabinet wall. Why is this a defect?
Answer: Flexible connectors must not pass through walls, floors, or ceilings
Flexible gas connectors are not rated for concealed or enclosed installations and must remain accessible and visible; passing through a wall creates a hidden leak hazard.