Gasfitting Theory Period 2 (CND) Flashcards
True or False: Piping or tubing may be supported by any larger pipe in the system?
False; Clause 6.8.3.
Threaded schedule 40 steel piping maybe used for pressures not exceeding _______ psi.
125psi; Clause 6.2.3.
Every hose and hose fitting shall have a minimum pressure rating of _____ psi.
350psi; Clause 6.2.9
True or False: Natural rubber maybe used as a gasket material?
False; Clause 6.9.7
True or False: A defective section of gas piping or tubing maybe repaired by a qualified gasfitter?
False; Clause 6.14.1
A hose maybe used to connect an unvented appliance when it is______________.
Mobile or requires isolation from vibration;; Clause 6.20.2
A corrugated metal connector shall not exceed 2’ in length when connecting a _____________.
suspended appliance or a decorative appliance.; Clause 6.21.3 (b)(c)
Plastic piping shall only be used for _______________.
Outdoor or underground service; Clause 6.2.16
True or False: Nesting of bushings is permitted on low-pressure gas piping.
False; Clause 6.14.2
True or False: A girder, beam or joist maybe cut for the installation of piping.
True - Not so as to weaken it beyond its required purpose.; Clause 6.8.4
Tubing run inside hollow walls within 1.75” of the surface shall b protected by?
NO. 16 GSG (1.59mm) Plates or Sleeves; Clause 6.16.4
List 5 items a corrugated metal connector maybe used to connect. And shall be a maximum length of ?
Range, Refrigerator, Clothes dryer, Built-in counter or suspended or decorative appliances, or A room heater. And shall be a maximum length of 6ft.
Type L or G copper tubing maybe used underground when it has been __________________.
Coated with extruded PVC or Polyethylene resin at the time of manufacture.; Clause 6.2.7
A branch line must be the same diameter as the supply piping when it ?
Supplies an unknown future connection; Clause 6.10
Gas piping, tubing and fittings may not be reused unless they were used on?
Gas before and are in as good as new condition. Clause 6.1.2
A 2” NPS horizontal gas line must be supported every?
10ft; Table 6.1
A piping outlet that it not connected to an appliance shall be terminated by means of ?
A plugged/capped valve,
A cap or plug compatible with the pipe or tubing employed.; Clause 6.12.1
Underground tubing systems shall be joined be the means of?
Brazing (1000*F) approved mechanical compressing fittings or Approved flare fittings.; Clause 6.15.3
A dirt pocket shall be installed on the ?
Final drop serving an appliance other than a range, a clothes dryer.
A residential tubing system shall be identified at ?
6 foot intervals; Clause 6.17.3
True or False: The use of left and right handed couplings is not permitted on a gas piping system.
True; Clause 6.14.3
Piping or tubing shall be painted or coated when?
Outdoor piping, indoor piping or tubing systems are exposed to corrosive atmospheres.; Clause 6.16.1
Piping or tubing shall be located at least _____ below a commercial driveway or parking lot.
24”; Clause 6.15.4
For permanent installation, a hose shall not exceed _____ in length.
10 feet; Clause 6.20.3
The unthreaded portion of a piping outlet shall extend _____ through a ceiling or wall and ______ through a floor.
1” through a ceiling or wall and 2” through a floor. Clause 6.12.2
Piping or tubing extending from one building to another shall have a shutoff valve located at the?
exit of the first building and at the point of entry to the second building. Clause 6.18.8
A swing joint may not be installed in a ?
Concealed location. Clause 6.14.4
A construction heater shall be connected by a hose not less than _____ and no more than _____ in length.
15’ and no more than 75’.; Clause 6.20.1
A bushing maybe used to reduce one pipe size when made of?
Steel; Clause 6.9.10(a)
True or False: A vented appliance maybe connected by a hose.
False; Clause 6.20.1
A drip pocket shall be provided where?
Condensate may collect. Clause 6.13.5
Where a commercial appliance maybe affected by vibration a _______ maybe used.
Hose connection may be used. Clause 6.20.2
Tubing laid on a rooftop shall be supported continuously with?
Treated wood and planks. Clause 6.26.2
The volume of gas required for each appliance shall be determine from _______________ and/or the manufacturer’s specifications.
Appliance rating plate; Clause 6.4.2
Finished piping and appliance connections shall be checked under ___________ pressure with either a ___________ or a __________.
Normal Operating pressure with either Soap Solution or a Leak Detection Device. Clause 6.22.3(e)
An addition to an existing gas line is not subject to Table 6.3 when it is?
Less than 20’ long or is a welded tie in. Clause 6.22.4(a)(b)
When a piping system is purged outdoors, the purge point must not terminate closer than?
10 feet from a building or air intake. Clause 6.23.7(a)
The maximum range of a test gauge shall exceed the test pressure by at least ____ but not greater than ____.
at least 15% but not greater than 300%. Clause 6.22.2(b)
A 2” NPS welded gas line shall be tested to a pressure of ____ psig or _____ times maximum operating pressure for ____ minutes.
50 psig, 1.5 times, 180 minutes. Table 6.3
A gas line operating at 10” w.c. shall be designed to prevent the loss of no more than ?
1” water column .
A purge line shall be no larger than _______ NPS for purging a line up to 4” NPS water column.
1/2” diameter.
True or False: Underground piping maybe covered 24 hours before being tested?
False
Pressure and duration of tests shall be in accordance with?
Table 6.3
After an appliance is connected and before the gas is turned on a, check shall be made to ensure that?
No openings permit the escape of gas, etc. Clause 6.22.3(a)(b)(c)(d)(e)
All factory-wrapped or coated piping shall be tested to a minimum of ?
100 psi.
A test gauge shall have a minimum diameter of?
3”
A gas line 4” NPS or larger that has been tested with air must be purged with ________ or ________ and then purged with ______.
Carbon dioxide or Nitrogen and then purged with Gas.
List 3 appliances that are not to be connected to a venting system.
Gas ranges, Gas clothes dryers, Portable gas-burners appliances, Direct vent appliances, Gas lights, Any appliance approved for use without a vent.
A vent complying with ULC Standard CAN/ULC-S605 and consisting entirely of factory made parts, each designed to be assembled with the other without requiring field fabrication, and intended for venting gas appliances. these are constructed of a galvanized steel outer casing with an inner lining of aluminum separated by an air space (1/2” nominal). The maximum internal temperature is not exceed 470F (243C).
Type B Vent
A vent complying with ULC Standard CAN/ULC-S605 and consisting of factory made parts, each designed to be assembled with the other without requiring field fabrication, and intended for venting only wall furnaces for use with such type of vent. It is constructed of a galvanized steel outer casing with an inner lining of aluminum separated by an air space (1/2” nominal). The maximum internal temperature is not exceed 470F (243C). This vent is oval in shape.
Type BW vent
A vent complying with ULC Standard CAN/ULC-S609 and consisting of factory made parts, each designed to be assembled with the other without requiring field fabrication.It is constructed of a galvanized steel outer casing with an inner lining of stainless steel separated by an air space (1/2” nominal). The maximum internal temperature is not exceed 550F (288C).
Type L vent
What is the operating principle for a natural draft venting system?
Convection
What is the operating principle for an induced draft venting system?
Convection
Name the most common type of vent used for natural draft residential gas appliances?
Type B
What is the minimum allowable size (area) for Type B vent?
Equal to a 3” diameter pipe. Clause 8.13.3
What is the minimum internal dimension of a type BW vent?
2” (50mm) Clause 8.13.3
What is the minimum effective vent height for a Type B vent?
5 feet (1.5m); Clause 8.14.6
What shape may a gas vent be?
Any shape
True or False: All gas vents must terminate to the outdoors?
True
What is the minimum height of a gas vent termination above a flat roof?
2 feet (600mm); Clause 8.14.5