CHI CHI Plumbing Systems Inspection 2 — Questions and Answers
Question 1: A home inspector tests multiple faucets and finds low water pressure only at hot water fixtures. What is the most likely cause?
- Faulty pressure regulator
- Partially closed main shutoff
- Failing water heater dip tube (Correct answer)
- Clogged aerators on all fixtures
Correct answer: Failing water heater dip tube
A broken dip tube in a water heater can shed plastic debris that clogs aerators and cartridges on hot-side fixtures, reducing flow.
Question 2: What is the primary purpose of a backflow preventer installed on an outdoor hose bib?
- To regulate water pressure to safe levels
- To prevent contaminated water from re-entering the potable supply (Correct answer)
- To allow winterization of exterior lines
- To limit water flow to the irrigation system
Correct answer: To prevent contaminated water from re-entering the potable supply
A backflow preventer stops potentially contaminated water (from hoses submerged in pools, buckets, or chemicals) from being siphoned back into the potable water supply.
Question 3: According to standard inspection practice, what minimum drain pipe slope is required for proper gravity drainage in residential construction?
- 1/8 inch per foot
- 1/4 inch per foot (Correct answer)
- 1/2 inch per foot
- 1 inch per foot
Correct answer: 1/4 inch per foot
A slope of 1/4 inch per foot (2% grade) is the standard minimum for residential drain lines to ensure solids are carried along with liquid waste.
Question 4: A home inspector sees water stains on the ceiling below a second-floor bathroom. Which of the following is the FIRST area to investigate?
- The supply line shutoff valves
- The wax ring seal at the toilet base
- The tub or shower drain collar and caulk lines (Correct answer)
- The water heater anode rod
Correct answer: The tub or shower drain collar and caulk lines
Ceiling stains below a bath typically originate from tub or shower surround leaks at caulk lines or drain collars, which are the most common failure points.
Question 5: Which type of drain line material appears gray in color and was commonly used in homes built between 1978 and 1994 before being linked to joint failures?
- ABS
- PVC
- Polybutylene (Correct answer)
- Cast iron
Correct answer: Polybutylene
Polybutylene (PB) pipe, typically gray, was widely installed from the late 1970s through the mid-1990s and is known to fail at fittings due to chlorine reactions.
Question 6: When inspecting a septic system, which visible sign indicates the drain field may be failing?
- Dry, cracked soil over the leach field
- Lush, green grass growing over the drain field (Correct answer)
- A cleanout cap above grade near the house
- Multiple inspection ports capped with plastic covers
Correct answer: Lush, green grass growing over the drain field
Unusually lush or green grass over a drain field indicates that effluent is surfacing and saturating the soil rather than dispersing properly underground.
CHI CHI Plumbing Systems Inspection 2
A home inspector tests multiple faucets and finds low water pressure only at hot water fixtures.
What is the most likely cause?