Plumbing Theory Period 2 (CND) Flashcards
What is the reason for having a recirculation line on the hot water distribution line?
To supply hot water to the furthest fixture immediately.
If you were to rough in a bank of water closets, could you have one shut-off valve to serve the bank?
No, one valve is required per water closet.
Ballcock valves come in all shapes and sizes. What is the most important fact about them?
They must be of the anti-siphon type.
What methods are used to drain the water in the distribution lines in an unheated building?
Slope the lines to a drain or blow out the lines.
Installing a check valve on a water service near the house shut-off valve, creates a?
Closed water system.
The only time you can inter connect public and private water system is ?
Never, it cannot ever be done.
When testing water distribution systems, the test will be an?
Air test at 100 psi for 2 hours.
The maximum pressure at the fixture in a water distribution system is?
550 KPag
A pressure reducing valve is needed when?
The pressure exceeds 550 KPag.
The higher the pressure in a water distribution system?
The noisier the flow.
Water meters are used for?
Metering water consumption, detecting leaks in the system, metering certain fixtures and billing purposes.
A meter bypass must be installed in the meter is?
Larger than 1-1/4”
What is the smallest size of service pipe allowed?
3/4”
What is the requirement for size when servicing more than one fixture with the water heater?
3/4”
What are the 3 requirements for using the simplified method of water sizing?
- Separate water services
- The total developed length of this water system measured from the most or furthest fixture to the property line is not more than 90m.
- The minimum static pressure at the water service entry, usually the building isolation valve is not less that 200kpa.
The information needed for sizing water distribution system is?
Pressure at the building isolation, distance from the main to the farthest faucet.
The pressure at the curb cock will not be the actual pressure used for sizing because?
The minimum pressure at the building isolation must be atleast 200kpa.
When sizing the water service, you will?
Size is according to the total cold fixture units.
Residential instantaneous water heaters are designed for?
Low flow rates.
In gas fired hot water tank, the largest volume of hot water is located?
At the top due to the density factor.
Hot water tanks are usually rated for a maximum working pressure of?
150 psi
The electric hot water tank has?
An anode rod since it may be exposed to corrosive water.
Hot water tanks are sized according to the?
Number of building occupants
The lowest opening in a hot water tank is for?
Drain valve
The hot water tank dip tube is?
For directing the cold water down to the bottom of the tank.
The maximum temperature allowed in a hot water tank is?
210F or 99C
The discharge pipe on a temp. and pressure relief valve must drop down to within ______ of the floor.
12” or 300mm
An energy cut-off (ECO) can be used instead of?
A temperature relief valve.
A vacuum breaker on a bottom feed hot water tank Replaces?
The small hole drilled in the dip tube.
An indirect service hot water tank is usually heated by?
Hot water.
Upon entering an occupants home to unplug a floor drain, you notice that a cap has been placed on the hot water tank temperature and pressure relief valve, so you?
Inform the owner of the risk and ask to repair it
After completing an installation of a complete water distribution system you?
Flush all the lines, including the clothes washer and dishwasher lines.
Dual venting is a method of venting in which _______ trap seal(s) is/are protected by means of _______ vent pipe(s).
2 trap seals, 1 vent pipe.
Name 3 fittings that may be used for dual venting.
Double tee wye
Double wye
Side inlet tee wye (Bungalow fitting)
The waste pipes of dual-vented fixtures must connect at?
The same level.
The number of dual vents required for 16 similar fixtures is?
8.
True or False: Where dual venting is employed, the fixtures must be identical
False; The connection of the trap arms t the branch must be at the same elevation.
A flat vent is used when the vent must run _______ and _______ the flood level rim of that fixture.
Horizontal and Below
Two fixtures that use the flat vent are the ________ and the _______.
Kitchen sink and Bathtub.
When a flat vent is installed it must be equipped with a _______.
Cleanout.
The flat vent is sized as an ________ or _________ vent.
Individual or Dry vent.
The table that is used to size a flat vent is?
Table 2.5.7.1
A flat vent should change to the ______ position as soon as possible.
Vertical
True or False: There limitations on distance when using Table 2.5.7.1?
False
The correct term for a vertical rainwater pipe located inside a building is a?
Rainwater leader.
2 acceptable terms for rainwater pipes located outside a building are ________ and _________.
downspouts and rainwater leaders.
List 5 pipe materials that are acceptable for both above ground sanitary drainage and rainwater leaders.
ABS, PVC, CI, DWV Copper & Galvanized steel pipe.
Another name for an underground drainage system is?
Subsoil drainage
Weeping tile water preferably goes to the _______ instead of to the ________ sewer.
SOTRM SEWER instead of to the SANITARY sewer.
Name 5 methods for disposing of subsoil drainage.
Storm sewer, Combined sewer, Sanitary sewer, Sump pit, and Above ground (*on a splash pad, directed to a drainage ditch, directed to a catch basin)
When the weeping tile is to be connected to the sanitary building drain, a ________ and a _______ must be installed.
BACKWATER VALVE and a P TRAP must be installed.
A wet vent pipe acts as a/an _____ pipe and also as a/an ______ pipe.
WASTE pipe and also as a VENT pipe.
2 or more fixtures can be involved in a wet venting arrangement. When 3 or more fixtures are involved, the top fixture is considered t be __________ vented and the balance of the fixture in the group are considered to be _________ vented.
Dry Vented and Wet Vented
The primary purpose of wet venting is for?
Economy of piping.
A wet vent starts ________ of the first or highest connected fixture on a common vertical pipe.
Downstream
Yes or No: Do the fixtures involved in a wet venting arrangement need to be located on the same floor level?
No
The minimum size of a continuous vent is ?
1-1/4”
How is a wet vent sized?
Full size throughout.
Continuous vents are sized from table _______ and then cross referenced to table ______.
Table 2.5.8.3 and cross referenced to Table 2.5.7.1
The combined wastes from a lavatory and single compartment sink are used to wet vet a 3” water closet. The wet vent size should be ?
2”
The slope on a horizontal wet-vented waste pipe, 3” in size or smaller, is a minimum of?
1:50 or 1/4” per foot or 2%
When sizing the waste or soil pipe section between fixtures, using common vent, the pipe is classified as a/an ________ vent and is sized from table _____
An WET vent and sized from TABLE 2.5.8.1
When sizing the vertical portion of the wet vent, do not include the fixture unit load of the _______ connected fixture.
the LOWEST
To size a continuous vent, you must first determine the size of the vent according to table ______, then based on the largest trap size in the system, ensure that table _____ has been satisfied.
Table 2.5.8.3 and Table 2.5.7.1
The lowest connection on a vertical single story wet vent is?
Water Closet
Table 2.5.7.1 is used to size ?
All Vents.
A vent pipe that is used in conjunction with a circuit vent to provide additional air circulation between a drainage system is called a?
Relief Vent
A circuit vented branch is defined as the drainage piping between the ?
Relief vent and circuit vent.
A circuit vent connects to ?
The trap arm of the most upstream fixture
What is the maximum number of water closets that may drain into a circuit vented branch?
There is no maximum.
Where are circuit vented systems allowed to be installed?
Residential, Commercial, and High rise apartment buildings.
How are wet venting and circuit venting systems similar?
Both systems use the upper portion of a horizontal drainage pipe for venting multiple fixtures.
Is it permissible to drain 1-1/2” trap arms into a circuit vented branch that also serves 2” trap arms?
Yes, but only if the 1-1/2” trap arms are separately vented.
What is the maximum hydraulic load permitted to drain into a relief vent?
6 fixture units
What is the maximum hydraulic load permitted to drain into a circuit vent?
3 fixture units
What is the minimum size permitted for a circuit vented branch that serves 2” trap arms?
3”
What is the minimum size permitted for a circuit vented branch that serves only 1-1/4” trap arms?
2”
Which table is the National Plumbing Code is used to size a circuit vented branch?
Table 2.4.10.6B
What is the minimum size of a relief vent for a circuit vented branch that serves water closets?
1-1/2”
What is the minimum size of the wet portion of a circuit vent that has one lavatory draining into it, if the circuit vented branch serves water closet?
2”
Which Table in the National Plumbing Code is used to size circuit vents?
Table 2.5.8.3
When installing a relief vent on the horizontal portion of a circuit vented branch which of the following would be the best procedure?
Using a wye fitting with the outlet rolled above the horizontal centre line of the circuit vented branch.
Which article in the National Plumbing Code describes the requirements for circuit venting?
Article 2.5.3.1
Which article in the National Plumbing Code describes the restrictions on draining fixture into the circuit vent?
Article 2.5.4.5
Piping should be installed so their markings are __________ and ___________.
Facing up when installed in a trench and facing down when hung on hangers.
When installing pipe underground, the ditch should be _________________.
Smooth and without any high spots.
When placing any pipes under or through a foundation you should prevent the foundation from ____________.
Bearing any weight on the pipe.
When back filling a trench the first _______ mm should be done by hand using small compatible aggregate.
300mm
Can you use a sanitary tee on its back to connect on fixture drain to another?
No; A sanitary tee on its back can only be used to connect a dry vent.
Can you purchase a 2” expansion joint?
Yes; Expansion joints are manufactured in sizes 1-1/2” through 4”.
Does ABS pipe expand more than PVC pipe?
Yes,
The maximum trap arm length of a minimum size floor drain is ?
2.4m or 8ft
The size of a cleanout is determined by the size of the _________ but does not need to be any larger than ____ for pipes over 4”.
Drainage pipe, 4”
If you have a 4” building drain connected to a 3” soil stack, what would the size of the cleanout at the base of the stack be?
4”
When you are uncertain if a bathtub trap will be accessible or not, what would be the solution?
Make the P-trap a solid joint style.
What is the cheapest method of venting?
Stack vent is the most economical method. This wet vent method allows for one vent to serve many fixtures.
Yes or No: Can you have two basins tied together by continuous waste system?
Yes; The can be 2 single sinks or basins on one trap using the continuous waste method.
Can you have an 1-1/4” waste branch?
Yes; Table 2.4.10.6.B
A wet vent will be sized according to what table?
Table 2.5.2.1
If a fixture is not listed on Table 2.4.9.3, the size of the trap will determine it fixture units by using table?
Table 2.4.10.2.
According t the NPC, to size a building drain, you must know the _________ and the __________.
The total fixture units and The amount of grade on the pipe.
According to Table 2.4.9.3, the smallest P trap is ___ inch for one shower head.
1-1/2”
How do you size a continuous vent?
Number of fixture units venting into it.
How do you decide the size of the trap arm?
By either Table 2.4.9.3 or according to its fixture outlet pipe.
Why is a material list so important for a job?
A list assists in tracking materials that are used or required on a particular job.
Yes or No: Does a plumbing vent that is installed above the flood level rim of a fixture need to be leak tested?
Yes; The NPC says all DWV systems need to be tested for leaks.
What is the minimum time required for a leak test using water?
15 minutes
When pressure testing a drainage system, what is the tool needed to hold the pressure in the piping being tested?
A test plug.
Grinds food to a pulp stage so that it is small enough to flow down the drain with the assistance of cold water?
Garbage grinder
Prevents blocked drains by not allowing soap bars and other large objects to enter the drain.
A shower strainer.
Provides janitors with a place to fil and empty floor washing pails.
Service sink.
A residential garbage grinder has ___ load when connected to a kitchen sink.
No load.
When a dishwasher is not located near the kitchen sink, the drain will have to be?
Individually supplied and installed complete with a P-trap, and it will by protected by a vent.
What table is used to find a fixture unit rating for an automatic clothes washer?
Table 2.4.9.3
The minimum size of a P-trap for a service sink is ?
2”
The difference between a service sink and mop sink is?
A service sink is wall mounted and a mop sink is floor mounted.
What is the minimum size of a P trap for a residential shower?
1-1/2”
What is the minimum size of water supply required for a dishwasher?
1/2”
Garbage grinder knives are made from?
Steel or stainless steel.
What additional fixture should be supplied with clothes washers?
A floor drain
Service sinks are generally made from?
cast iron
Prebuilt showers have a __________ membrane.
Built-in waterproof membrane.
2 common shower membrane materials.
PVC liner and Lead sheeting.
2 names of garbage grinders?
Batch feed grinder and Continuous feed grinder
Which is the safest grinder to operate?
Batch feed grinder
Should hot or cold water flow through a garbage grinder when in operation?
Cold water should be ran through the grinder. But hot water breaks down the grease and allows it to cling to the pipe.
On a batch feed grinder the control switch is located?
Internally.
When installing a garbage grinder, the mounting ring has three screws that are meant for?
Drawing the flange snug to the base of the sink.
When placing the flange of the grinder onto the sink, you should place it so the?
Writing or symbols face up to the person looking at it.
Can you test the drain for leaks even if the power is not connected to the grinder?
Yes.
What is the minimum size for a residential laundry stand pipe?
2”
Before installing any fixture, the first step is to?
Open the box and check to see if all the parts and manuals are there.
Before installing any fixture you must refer to the?
Manufacturers rough in book.
To hold up a service sink a _______ is supplied.
Support bracket
The height of a service faucet, from centre of the faucet to the floor is?
30”
Mop sinks should have an opening in the floor for the fixture outlet of at least?
6” in diameter.
What is the height of a shower head from the floor?
6’6” from the floor to the centre.
What size of P trap does a residential garbage grinder require?
1-1/2”
If a dishwasher were to have its own trap it would be?
1-1/2” in size.
With the water supply tubing connecting the dishwasher, what 2 other components are required?
Isolation valve and Adapter to the solenoid valve.
Why must laundry water supplies have shutoff valves?
So servicing of the appliance can be done easily.
Where should the hole for the dishwasher drain hose be located in the cabinet?
It should be located as high as possible in the cabinet.
What is the hydraulic load of a dishwasher connected to a garbage grinder?
Zero fixture units .
Why must you make a high loop on the dishwasher drain hose?
This prevents waste from backing up into the dishwasher.
2 methods for trapping a garbage grinder?
it could be connected to the adjoining sink with the means of a continuous waste.
or
It may have its own trap and trap arm to the waste connection.
What is the hydraulic load of a commercial garbage grinder that has its own 2” P trap and what table did this info. come from?
Hydraulic load - 3 fixture units
and, Table 2.4.9.3
The size of the individual vent to be installed on a fixture drain to a garbage grinder is ___ inched, which is found in table_____.
1-1/4” and Table 2.5.7.1.
A triple compartment sink will need a minimum of a ?
2” P trap.
Before troubleshooting a garbage grinder, ensure that the?
Power is turned off.
With the electrical brought to the dishwasher location what is the first step in installing this appliance?
Ensure that the panel switch is off for the dishwasher.
Yes or No: With the dishwasher in place and water and sewer connected, are you permitted to connect the electrical to the unit?
No; You need a qualified electrician to connect it.
Before installing a used fixture is must be ?
Inspected to meet todays standards.
What is the minimum water supply pressure to a fixture?
50 kpa or 7 psi
What is the maximum water supply pressure to a fixture?
550 kpa or 80 psi
Why are concealed overflows NOT permitted on kitchen sinks?
I prevents fungus and bacteria build up in the overflows.
What has t be done before a two piece ball valve can be serviced?
Remove the valve from the piping to take apart.
What identification must a ball valve use in natural gas service?
It must be stamped by an approved testing agency.
What is the direction of flow through a conventional disc globe valve?
Flow should be from under the seat.
What is the advantage of having a OS and Y gate valve on a fire service?
East to see if the valve is open.
What kind of check valve should be used for a low velocity heating system that uses ball valves for isolation?
Swing Check Valve.
What are 2 advantages of composition disc globe valves?
Higher resistance to erosion and Positive seal when particles accumulate on the seat.
Where would you locate a firing valve?
gas train to large appliances.
What kind of end connections will you find on a corporation main stop?
AWWA Thread on one end and either a flare or compression on the other.
4 factors that should be considered when choosing the correct valve for an installation?
Pressure, Temperature, Volume and Type of Fluid
State the purpose of the Stuffing Box?
To prevent fluid leakage
State the purpose of the Packing Nut?
To hold the packing which prevents fluid leakage
State the purpose of the Packing Gland?
To compress the packing
State the purpose of the Lantern Ring?
To lubricate the valve stem
When would you choose a globe valve instead of a gate valve?
Any time a throttling application of flow control is required.
What is the recommended position that a valve stem should be installed?
Upright vertical position
The loss of pressure in the line caused by the valve or fitting in relationship to a length of pipe is ?
Equivalent length
The difference between the restriction (relative to the equivalent length of pipe) of a 3/4” gate valve fully open and a 3/4” globe valve fully open is?
19.5ft
The difference between a 2” gate and globe fully open is?
53.7ft
The meaning of NRS?
Non-rising stem
The meaning of AWWA?
American Water Works Association
The meaning of RS?
Rising stem
The meaning of WOG?
Water, Oil and Gas
The meaning of S ?
Steam
The meaning of 125WOG ?
125 psi max. operating pressure (Water, Oil and Gas)
The meaning of 125S?
125 psi max. operating pressure (Steam)
The meaning of CGA?
Canadian Gas Association
What types and designs of valves would be best suited for Laminar flow, Non throttled?
Ball or Gate valve
What types and designs of valves would be best suited for Very close throttling?
Needle Valve
What types and designs of valves would be best suited for Restricted headroom-non throttling?
Ball or Non-rising stem gate valve
What types and designs of valves would be best suited for Change direction and throttle?
Angle globe valve
A 1” steam boiler blow down valve is required to manually remove sludge and sediment on a daily basis. Which valve type and/or designs would be used?
Quick opening gate valve and Y pattern globe valve.
A check valve is required downstream of a domestic cold water booster pump that cycles frequently. All piping is 3” flanged and uses butterfly valves for isolation. Which valve type and/or designs would be used?
Non-Slam check valve
Isolation valves are required on domestic hot and cold 3/4” branch piping to individual hotel suites. Which valve type and/or designs would be used?
Solid wedge gate valve or ball valve.
Automatically controlled balancing of flow is required on a bank of 3 heating coils in a ventilation plenum. All piping is 3” and flanged. Which valve type and/or designs would be used?
Lug wafer butterfly valve with actuator
A throttle type supply valve is required for an old style cast iron hot water heater. Supply piping 3/4” comes up through the floor and there is no room for 90 degree elbows. Which valve type and/or designs would be used?
Angle globe valve
All zones for fin tube radiation is a high rise office building require a balancing valve for the return. Pressure drop is not an issue. Which valve type and/or designs would be used?
Lock shield straight pattern globe valve.
A 2” low velocity line with suspended particles requires a horizontally mounted check valve that provides positive shut off. Which valve type and/or designs would be used?
Lift check valve with composition disc
Several fan coil units require compact isolation valves for 1/2” hot water heating supply and return valves. there is limited area within the fan coil hook up compartment. Which valve type and/or designs would be used?
Ball valve
A check valve is required downstream of a continuously running circulation pump in a mechanical room. This is a 4” high volume heating supply line and noise is not a consideration. Which valve type and/or designs would be used?
Lift check valve with metal to metal disc and seat or a swing check valve.
A frequently used 3” isolation valve on a line that contains suspended debris requires dependable and positive shut off. Which valve type and/or designs would be used?
Split wedge gate valve
Multiple lines in a food processing plant require 1” and 2” manually operated regulating valves. Which valve type and/or designs would be used?
Diaphragm valve
A 2” threaded supply line in a steam system that is subject to extreme temperature changes requires an isolation valve. Which valve type and/or designs would be used?
Flexible wedge gate valve
A 3/4” natural gas line drop to a furnace requires an appliance shut off. Which valve type and/or designs would be used?
CGA approved ball valve or gas cock
A 1/4” compressed air line requires a constant, consistent ,accurate and fine-tuned air flow to a delicate dental drill apparatus. Which valve type and/or designs would be used?
Needle valve
A bank of natural gas meters with 1-1/4” outlets, require separate isolation valves to several individual row housing units. Which valve type and/or designs would be used?
Lockable gas valve
A 1” high density polyethylene gas service to a single family dwelling that changes from plastic to black malleable iron above grade requires a shut off. Which valve type and/or designs would be used?
Insulated service valve.
A 1-1/4” throttling type valve is required in a process waste line that contains suspended scale and debris. Which valve type and/or designs would be used?
Straight pattern globe with conventional disc
Preset temperatures on a hot water tank?
140 degrees F
Dip tube ?
It’s a tube that pushed cold water from the top of the tank to the bottom
Electric hot water tanks require 120v or __v power supply?
240volts
Storage tanks are _______ centre flue type tank.
Concave
The side of a storage tank has three openings the top opening is within 6” off the top of the tank this is for the ?
The other two opening are ?
Pressure relief valve.
Gas control and drain valve
The anode rode is typically known as ?
Sacrificial anode
Dip tube is called ?
Anti siphon hole
A temperate relief vales pop at what temp to reduce tank ?
99degrees c or 210 degrees f
The most common domestic gas fired hot water tanks are ?
30 us gallons 40 us gallons and 50 us gallons.
A 40 gallon hot water tank gas fired has a voltage of ?
120-240volts
The pressure should be located so that the pressure in the tank does not exceed the pressure of the relief valve by ?
35kpa or 5 psi
At the bottom of a drop for a temp relief valve on a hot water tank the air break need to more no more then?
12” or 300mm off the floor
Cut drop piece of copper on a temp relief valve at a ?
45 degree angle
What’s frost heave ?
When there’s no wheeping tile installed causing the ground to be soaked and when the water freezes it expands agains your foundation cracking it.
A combined sewer is ??
No longer allowed !
Every rainwater leader needs what ?
P trap and a back water valve
Ever rain water leader needs to be no more than ?
3 meters upstream from the bottom of the leader
Another name for wheeping tile ?
Subsoil drainage
First storey does. It exceed ___ fixture units
4
The offset does not exceed ___m for pipes 2 inches or less in size?
1.2M
The offset does not exceed ___m for pipes larger then 2 inches in size.
2.5m
The length of a wet vent is limited true or false
False it can run as far as you want !
