CHI CHI Plumbing Systems Inspection 1 — Questions and Answers
Question 1: When inspecting a water heater, what is the minimum required clearance between the relief valve discharge pipe and the floor drain?
- 6 inches (Correct answer)
- 12 inches
- 18 inches
- 24 inches
Correct answer: 6 inches
The TPR valve discharge pipe must terminate within 6 inches of the floor to safely direct scalding water away without creating a hazard.
Question 2: Which pipe material is most commonly identified by its blue or black color and is approved for cold water supply lines in residential construction?
- CPVC
- PEX (Correct answer)
- PVC
- Galvanized steel
Correct answer: PEX
PEX (cross-linked polyethylene) is commonly color-coded blue for cold water and red for hot water in residential plumbing systems.
Question 3: A home inspector observes that a p-trap under a bathroom sink is installed without a vent pipe. What issue should be documented?
- Inadequate water pressure
- Sewer gas infiltration risk (Correct answer)
- Cross-connection hazard
- Insufficient drain slope
Correct answer: Sewer gas infiltration risk
Without proper venting, negative pressure can siphon water out of the p-trap, allowing sewer gases to enter the living space.
Question 4: What is the maximum water pressure recommended at the point of entry to a residential plumbing system according to most US plumbing codes?
- 60 PSI
- 80 PSI (Correct answer)
- 100 PSI
- 120 PSI
Correct answer: 80 PSI
Most US plumbing codes recommend a maximum static water pressure of 80 PSI at the service entry to prevent damage to fixtures and appliances.
Question 5: During a home inspection, the inspector notices galvanized steel supply pipes with visible orange staining at joints. What is the most likely concern?
- Lead contamination
- Internal corrosion reducing water flow (Correct answer)
- Excessive water pressure
- Improper pipe sizing
Correct answer: Internal corrosion reducing water flow
Orange staining at joints of galvanized pipes indicates internal rust and corrosion, which progressively reduces pipe diameter and water flow.
Question 6: Which condition would a home inspector classify as a safety deficiency when evaluating a gas water heater installation?
- A water temperature set to 120°F
- A flue pipe that slopes upward toward the chimney
- A missing seismic strap in a non-seismic zone
- Combustion air drawn from inside the conditioned space (Correct answer)
Correct answer: Combustion air drawn from inside the conditioned space
Gas water heaters require adequate combustion air; drawing it from a small enclosed space can cause incomplete combustion and carbon monoxide production.
CHI CHI Plumbing Systems Inspection 1
When inspecting a water heater, what is the minimum required clearance between the relief valve discharge pipe and the floor drain?