InterNACHI Plumbing & HVAC Systems 3

Question 1

Which condition in a plumbing system is described as water hammer?

Accepted Answer

Banging noise when a valve or faucet is quickly shut off

Answer

Water hammer is the banging or thudding sound caused by the sudden pressure wave when fast-moving water is abruptly stopped by a closing valve.

Question 2

What does AFUE stand for in reference to heating equipment, and what does a higher number indicate?

Accepted Answer

Annual Fuel Utilization Efficiency; higher means more efficient

Answer

AFUE (Annual Fuel Utilization Efficiency) measures how much fuel is converted to heat; a rating of 95% means 95% of fuel energy becomes useful heat.

Question 3

An inspector notices that a bathroom exhaust fan vents into the attic instead of to the exterior. What is the concern?

Accepted Answer

Moisture and mold can accumulate in the attic

Answer

Exhausting humid bathroom air into an attic introduces moisture that can lead to condensation, wood rot, and mold growth on framing and sheathing.

Question 4

What is the minimum required distance between a gas water heater's pilot or burner and the floor in a garage installation?

Accepted Answer

18 inches

Answer

In a garage, ignition sources such as pilot lights must be elevated at least 18 inches above the floor to reduce the risk of igniting gasoline vapors that pool low.

Question 5

Which refrigerant was widely phased out of residential air conditioning systems due to ozone depletion concerns?

Accepted Answer

R-22 (Freon)

Answer

R-22 (chlorodifluoromethane, marketed as Freon) was phased out under the Clean Air Act because its chlorine atoms deplete stratospheric ozone.

(InterNACHI) International Association of Certified Home Inspectors Practice Test

(InterNACHI) International Association of Certified Home Inspectors Practice Test

InterNACHI Plumbing & HVAC Systems 3