InterNACHI Plumbing & HVAC Systems 2

Question 1

What is the minimum slope required for a horizontal drain pipe to ensure proper drainage by gravity?

Accepted Answer

1/4 inch per foot

Answer

A minimum slope of 1/4 inch per foot (2%) is required for horizontal drain pipes 3 inches or smaller to maintain adequate flow velocity.

Question 2

A home inspector observes a water heater with no pressure relief valve discharge pipe. What is the primary concern?

Accepted Answer

Steam and hot water could spray dangerously if the valve opens

Answer

Without a discharge pipe, an opening T&P valve could spray scalding water or steam directly at occupants, posing a serious burn hazard.

Question 3

What does a home inspector look for when checking an air conditioning evaporator coil?

Accepted Answer

Ice buildup or blocked condensate drain

Answer

Ice on the evaporator coil indicates restricted airflow or low refrigerant, and a blocked condensate drain can cause water damage or system shutdown.

Question 4

Which type of pipe is most commonly identified by its blue or black color and is acceptable for potable cold-water supply lines?

Accepted Answer

PEX

Answer

PEX (cross-linked polyethylene) is commonly color-coded blue for cold water and red for hot water, and is approved for potable water supply.

Question 5

An inspector finds a gas furnace with a cracked heat exchanger. What is the recommended course of action?

Accepted Answer

Recommend immediate discontinuation of use and professional repair

Answer

A cracked heat exchanger can allow carbon monoxide to mix with supply air and enter living spaces, making it a life-safety issue requiring immediate action.

(InterNACHI) International Association of Certified Home Inspectors Practice Test

(InterNACHI) International Association of Certified Home Inspectors Practice Test

InterNACHI Plumbing & HVAC Systems 2