Plumbing Unit 13 - Principles of Home Inspection Systems & Standards
51. List seven different materials used in piping for drain, vent waste systems.
Copper, ABS plastic, PVC plastic, cast-iron, lead, galvanized steel, brass, clay.
71. List 5 common materials used in venting systems.
Copper, galvanized steel, cast iron, pvc, abs
3. List 6 materials commonly used for water service piping (from the main to your house).
Copper, galvanized steel, lead, PVC, CPVC, Polybutylene, cast iron, asbestos cement, brass.
6. List 5 materials used a water supply plumbing (in the house).
Copper, galvanized steel, polybutelyne, polyethelene, PVC, CPVC, brass, stainless steel.
78. What is the minimum height of vent pipe above the roofline?
6 inches
36. Where does the discharge tube from the temp/pressure-relief valve have to dump water in a cold climate?
6 inches above the floor beside the hot water tank
9. What is the recommended horizontal spacing of supports for copper piping?
6 to 10 feet.
37. Where does the discharge tube from the temp/pressure-relief valve have to dump water in a warm climate?
6 to 24 inches above the grade level, outside the house.
23. What is the approximate temperature rise designed in residential water heaters?
90F
17. Vertical pipes at the ends of runs are one way of preventing water hammer.
True.
33. Gas and oil-fired heaters are not allowed in sleeping areas?
True.
57. Pipe size should always increase as you move downstream and more fixtures join in.
True.
61. Every trap should be provided with some method of removal or cleaning?
True.
85. Sewage ejector pumps should not vibrate significantly when running. T/F
True.
34. How high above the floor should a gas or oil-fired water heater be in the garage?
18 inches
7. When was copper supply pipe first used?
1930s.
79. At least how far should an outdoor vent termination be above an operable door?
2 feet.
81. What is the typical vent size on a sewage ejector pump?
2 inches.
64. What is the max distance between the fixture and the trap.
24 inches.
87. Surface cracking in an acrylic kitchen sink is not usually a concern because there is no leakage.
True.
100. Running toilets are less prone to sweating because the water in the tank is constantly replenished.
False.
48. A waste pipe is intended to carry solids only.
False.
53. Copper pipe does not rust.
False.
62. A running trap is a good idea because it provides extra protection?
False.
67. It is impossible for a trap to be too big.
False.
74. The vent is typically located upstream of the trap. T/F
False.
75. Nearly horizontal vent pipes should slope slightly downward away from the trap they are protecting. T/F
False.
76. The vent diameter must be as large as the trap diameter.
False.
88. Testing for loose wall-hung basins is best done by putting all your weight on the basin. T/F
False.
47. A toilet does not need a vent.
False. (A toilet is vented at the waste pipe)
35. Where does the probe for the temperature/pressure-relief valve sit in the tank?
Upper 6 inches.
14. List 5 locations in a house where there may be a cross connection.
-Fixtures where the faucet spout is below the overflow or flood rim of the fixture. -Fixtures where handheld showers, extendable faucets, or vegetable sprayers can be left in tubs, basins or sinks. -Garden hoses attached to a hose bibb -A toilet tank where the fill water enters at the bottom -A dishwasher where the solenoid valve separates the clean water from the gray water -A clothes washer discharging into a laundry tub -A water softener -A humidifier connected to the supply piping -A lawn or fire sprinkler system -A bidet where the water enters at the bottom of the bowl -A hot water boiler -A swimming pool fill outlet located below the flood level of the pool -A trap primer without an air gap.
1. What are the three things that go wrong with water supply?
1) Pressure or flow is insufficient. 2) Leaks. 3) Dirty water.
28. What are the two methods of rating a water heater?
1) Volume of water 2) Size of burner.
56. What is the required slope for horizontal pipes in drain, waste and vent systems?
1/8 to a ½ inch fall per foot run.
21. Can polybutylene piping be used on a hot water recirculating loop?
No.
44. Are fan-assisted water heaters condensing?
No.
26. Where is the burner located on gas- and oil-fired water heaters?
The burner is at the bottom of the tank.
86. What is the purpose of a high-level alarm with a sewage ejector?
To warn the occupants that the sewer ejector pump has failed (is about to fail?)
2. Evaluating the quality of water available at a private source is beyond the scope of a standard home inspection.
True
20. Polybutylene supply piping should not be closer than 18 inches to a water heater.
True
10. What is the recommended horizontal spacing of supports for galvanized steel piping?
10 to 12 feet.
13. Briefly describe a cross connection.
A cross connection is a piping arrangement in which waste can back up into the piping supply and contaminate it when the pressure drops on the supply side.
29. How are these two related?
A large burner means a higher recovery rate, which means you can install a smaller tank.
96. Describe in one sentence each two types of hose bibbs.
A stop and waste valve prevents water from sitting where the pipe will freeze by isolating the through-wall section of pipe, and draining the trapped water out through the water valve. A frost-proof valve prevents water from sitting where the pipe will freeze by having the valve body remote from the hose bibb, and a slope to drain to the exterior.
80. What are the three components required on the discharge line from a sewage ejector pump?
A union, a gate valve, a check valve.
50. Explain briefly what is meant by a wet vent.
A wet vent is when the drain for one fixture is serving as the vent for another.
42. What are the two primary materials for the exhaust pipe on a fan-assisted water heater?
ABS or PVC piping.
38. If we only need a pressure relief valve, where should it be?
Anywhere on the tank, or on the piping near the tank in some jurisdictions.
65. What is the minimum trap arm length?
At least two pipe diameters.
68. Where should the floor drain be located?
At the low point of the floor.
18. Why can plastic piping not be used between units in shared dwellings?
Because it is combustible.
40. Why may an explosion with propane be more likely than with natural gas?
Because propane is heavier than air, and can accumulate, especially in a low area.
90. Why is water hammer more common in houses with cartridge faucets than with compression faucets.
Cartridge faucets can be opened and closed more quickly.
59. What is the implication of poor manifolding?
Clogging of pipes.
98. What can cause a toilet to sweat?
Cold supply water on a warm, humid day can cause the toilet tank and toilet fill pipe to sweat, particularly if it is not allowed to warm up because of a running toilet.
55. What is the implication of a cross connection?
Contamination of a potable water supply.
27. What is the component that introduces cold water near the bottom of a gas fired water heater tank.
Dip tube.
30. Which type of water heater has the slowest recovery rate?
Electric water heater.
8. At what interval is vertical support required for copper piping?
Every 10 feet or every floor level.
11. Plastic piping needs less support than copper piping because it tends to expand more.
False
41. When would a fan assisted gas water heater typically be used?
If the house has no chimney or if the chimney is too large.
43. List the common problems found with fan-assisted water heaters.
Inoperative, blower intake obstructer, poor venting, poor wiring
94. How is cross-connection with a hose bibb prevented?
Install a backflow prevention device.
54. List 2 methods of reducing the freezing risk of pipes in a cold environment.
Insulating the pipe; wrapping the pipe with heating cable.
58. Why is PVC or ABS plastic piping usually allowed only in single family homes?
It is combustible.
25. What is the biggest impact of the single pass feature on a water heater?
It is more prone to corrosion than a boiler because it is constantly exposed to fresh water.
49. Why in a cold climate is the trap portion of the drainage system most vulnerable to freezing?
It is the only portion of the drainage system that always contains water.
77. Explain briefly the problem with venting kitchen island sinks
Kitchen islands are not adjacent to walls, therefore, the vent pipe is some distance from the island, often exceeding the maximum allowable distance between trap and vent.
12. What is the implication of improper support on piping?
Leakage.
91. List 8 common faucet problems.
Leaking / rusting / inoperative / hot and cold reversed / obstructed aerator / loose / broken handle / shower diverter inoperative / noisy / cross-connection
72. Explain the simple test required to check the venting system when you test functional drainage from a fixture.
Listen for gurgling as the last bit of water leaves the drain, and smell for sewer odors.
73. List 7 problems found with vents.
Missing, Ineffective/incomplete, poor vent pipe arrangements, too small or too long, island venting problems, vent termination problems, automatic air vents.
15. Is a vacuum necessary to have backflow at a cross-connection?
No.
31. Which type of water heater has the fastest recovery rate?
Oil-fired.
63. List 4 types of traps that are not permitted in residential construction
S-trap, drum trap, bell trap, crown vented trap.
97. Describe in one sentence the stop and waste valve.
Shuts off the water and the drain cock drains water from the pipe.
5. What is the function of a stop and waste valve?
Shuts off the water supply and allows the system plumbing to be drained.
66.What is the implication of a trap arm that is too long?
Siphoning the trap.
95. List 7 common problems with hose bibbs.
Split pipe / Leaking / freezing / cracked or broken handle / incorrect slope on frost free bibbs / mechacnical damage / no backflow prevention
89. List two possible cross-connections at basins and sinks.
Sprayer left lying in a sink; extendable faucet.
32. Water running out of the burner compartment on start-up of a gas water heater suggests?
That condensation in the combustion chamber is running down through the center of the water heater and draining out the bottom.
19. Polybutylene piping failures seem to be concentrated most at:
The crimp rings.
52. Why are leaks more difficult to find in drain, waste and vent systems?
The pipes are usually idle and the water is not under pressure.
46. Explain why a toilet does not need a trap.
The toilet bowl itself is a trap.
84. What are the functions of the three pipes connected to a sewage ejector pump?
The vent pipe vents sewer gases, the discharge pipe handles the waste, and the drain pipe brings the waste into the pump.
24. A water heater is termed a single pass appliance because:
The water heater does not use a recirculating system. It sees the water only once.
83. Why is a check valve necessary when a sewage ejector is connected to municipal sewers?
This protects the ejector tank and house fixtures from backup of the municipal sewer system.
99. How is a mixing valve used to stop a toilet sweating?
This valve mixes hot water with the cold water at the toilet supply. There is less incentive for condensation because the warmer water used to fill the toilet won't cool the surrounding air to the dew point.
70. What is the purpose of the venting system?
To equalize the air pressure so the traps don't siphon.
82. What is the purpose of the sewage ejector pump?
To lift the waste from a toilet or any other fixture below the public or private sewer line, up into the sewer. They are needed when waste cant flow by gravity into the sewer system.
45. Describe the function of a trap.
To prevent sewer gases from entering the home.
60. What is the purpose of a trap?
To prevent sewer odors from entering the home through the plumbing fixtures.
69. Explain the purpose of a backwater valve.
To protect the home against sewer backup.
39. What is the purpose of the baffle or turbulator in a gas fired water heater?
To slow down the exhaust products as they move up through the heater.
16. Briefly describe water hammer, and why it occurs.
Water hammer is a loud banging sound in the pipes. Water hammer occurs because water moving at several feet per second has to stop abruptly when a valve is turned off. The water bounces off valve and creates a vacuum as it bounces away from the valve. The vacuum then violently attracts the water back to the low-pressure area, and the water again bounces off the closed valve. The effect of this is reverberation, which sounds like someone pounding on metal piping with a hammer.
92. List 3 types of faucet related noise.
Whistle, Chatter, Bang.
93. How is cross-connection possible with a hose bibb?
Without a backflow prevention device, outside water could be sucked into the plumbing system if the hose is attached, and the supply pressure drops below the atmospheric pressure.
22. A house with several different styles of crimp rings should be a cause of concern?
Yes
4. What is the typical minimum diameter of water service piping in modern construction?
¾ inch.