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Flashcards in Gas Code Deck (58)
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1
Q

A valve designed to activate when the fuel gas passing through it exceeds prescribed flow rate is a _____.

A

excess flow valve

2
Q

An appliance that operates with a non-positive vent static pressure and with a vent gas temperature that is capable of causing excessive condensate production in the vent is a _____ appliance.

A

category II

3
Q

Holes bored in a floor joist shall not exceed ____ their depth.

A

1/3

4
Q

Bored holes shall not not be greater than ____ of the stud depth in non-load bearing walls where each bored stud is doubled.

A

60%

5
Q

Gas appliances shall not be located in a ____ unless it meets one of the approved exceptions.

A

bathroom

6
Q

A single wall mounted unvented natural gas room heater equipped with an oxygen depletion safety system maybe installed in a ____.

A

bathroom if it is 6,000 btu’s or less

7
Q

Indoor combustion air for gas appliances using the standard method is sized based on ____ cubic feet per 1,000 Btu/h of the appliance input rating.

A

360

8
Q

How many cubic feet of space would be required to use the standard method of combustion air for gas appliances if you had a space with 60,000 but fan assisted furnace, 34,000 btu natural draft water heater, and 28,000 btu gas dryer?

A

61,000 cu ft

(total btu / 1000) * 50

9
Q

What would the maximum gas appliance btu input be for an open basement measuring 26’ x 52’ with 8’ ceilings, using the standard combustion method?

A

216,320 btu

(total cubic feet * 1000) / 50

10
Q

When combining spaces on the same story to obtain the required combustion air for gas appliances, each opening shall be sized a minimum 1 sq inch for the total input rating of all gas appliances but not less than ____ sq inches.

A

100

11
Q

The minimum dimension of air openings for combustion air for gas appliances is ____.

A

3 inches

12
Q

When using two permanent openings to provide combustion air for gas appliances and communicating directly with the outdoors, each opening shall have a minimum free area of 1 sq inch for every ____ total input rating of all equipment in the enclosure.

A

4,000 btu

13
Q

When installing all gas appliances ,combustion air is allowed to utilize one permanent opening commencing within 12” from the top of the enclosure. The opening must be a minimum 1 sq inch for every ____ total appliance input.

A

3,000 btu

14
Q

When mechanical combustion air is provided for gas appliances, the combustion air shall be supplied from the outdoors at a rate not less than ____ cfm per 1,000 btu/h of total input rating of all appliances located within the space.

A

0.35

15
Q

Where exhaust fans are installed, ____ air shall be provided to replace the exhausted air.

A

make up

16
Q

Where the design free area of louvers and grilles are not known, it shall be assumed that wood louvers have ____% free area and metal louvers will have ____% free area.

A

25,75

17
Q

Combustion air ducts for gas appliances shall not be ____ where terminating in an attic.

A

screened

18
Q

Condensate waste and drain line size shall not be less then ____.

A

3/4” ID

19
Q

Per the reduction table 308.2 2015 IFGC, when 0.5” insulation board is installed over 1” glass fiber or mineral wool batts, the required 12” clearance may be reduced to ____ for combustible items located above the vent connector for a gas water heater.

A

9”

20
Q

A gas furnace required to have 12” clearance to combustibles for the side of the appliance can be installed within ____ if the wall is protected with 0.024” sheet metal that has ventilated air space.

A

4”

21
Q

Gas central heating furnaces shall have the clearance from supply ducts within ____ of the furnace plenum but not less than that specified from the furnace plenum. No clearance is necessary beyond this point.

A

3 feet

22
Q

The bonding jumper for CSST must be a minimum ____ AWG copper wire.

A

6

23
Q

When adding an additional gas appliance to an existing gas system and the pipe system is found to have an inadequate capacity, the existing system shall be ____ as required or separate piping of adequate capacity shall be provided.

A

enlarged

24
Q

Gas piping shall be installed in accordance with ____.

A

-pip sizing tables located in section 402.4 of IFGC

-pipe sizing tables located in the appliance
manufacturers installation instructions

-other approved engineering methods

25
Q

Sizing a gas pipe system where each section is determined using the longest length of piping from the point of delivery to the most remote outlet and the load of the section is _____.

A

the longest length method

26
Q

Schedule 40 metallic pipe on natural gas with an inlet psi of 0.5 psi, a psi drop 0. inch WC, and specific gravity of 0.60 is supplying a 100,000 btu furnace. The length from the meter of the furnace is 60 feet. What is the minimum size of pipe allowed to be used?

A

3/4”

27
Q

Semi-rigid copper tubing 5/8” ACR at 100 feet total length on natural gas, with an inlet of 2.0 psi, a psi drop of 1.0, and a specific gravity of 0.60 has a maximum capacity of ____ btu/h.

A

296,000

28
Q

A 120,000 btu LP gas boiler located 80 feet from the second stage regulator requires a minimum ____ black pipe when the design has an inlet pressure of 11.0” w.c., 0.5” w.c. pressure drop, and a specific gravity of 1.50.

A

3/4”

29
Q

Steel and wrought-iron pipe for gas piping shall be at least a standard weight of ____.

A

schedule 40

30
Q

Plastic pipe and fittings for gas piping must conform to _____ and shall be installed outside underground only.

A

ASTM D 2513

31
Q

Gas pipe tubing joints shall either be made with approved gas tubing fittings or be brazed with a material having a melting point in excess of ____ degrees F.

A

1,000

32
Q

Plastic pipe joints and fittings for use in liquefied petroleum gas piping systems shall be in accordance with ____.

A

NFPA -58

33
Q

Gas piping installed downstream of the point of delivery shall not extend through any ____ other than the unit served by such piping.

A

townhouse

34
Q

Only gas piping joints made by ____ are approved in concealed locations.

A

brazed or welded fittings

35
Q

Gas metallic piping or tubing for LP gas systems require ____ to isolate the underground portion of the pipe between the storage container and the building piping.

A

an approved dielectric fitting

36
Q

Which is true of plastic pipe used for gas piping?

Used outdoors underground only
Not be installed under any building or slab
Not exceeds 100 psi for natural gas or exceeds 30 psi for LP gas

A

All

37
Q

Approved gas appliance connectors shall not exceed ____ in length.

A

6 feet

38
Q

3/4” steel gas pipe for gas pipe systems shall be supported every ____ feet.

A

8

39
Q

What type of gas appliance is not required to be vented?

A

ranges

40
Q

Gas utilization equipment shall not be connected to a chimney flue serving a separate appliance designed to burn ____.

A

solid fuel

41
Q

A type B or L gas vent shall terminate a minimum of ____ feet in vertical height above the highest connected equipment draft hood or flue collar.

A

5

42
Q

Gas vents that are 12” or less in size and located not less than 8 feet from a vertical wall that terminates through a flat roof must be at least ____ above the roof.

A

1.0 feet

43
Q

Where two or more gas appliances vent connectors enter a common gas vent, chimney flue, or single-wall metal pipe, the ____ shall enter at the highest level consistent with the available headroom and clearance to combustible materials.

A

smaller connector

44
Q

The maximum horizontal length of a single wall connector for gas appliances shall not exceed ____ percent of its chimney or vent height..

A

75

45
Q

A gas, single natural draft 40,000 btu input, water heater has a vent with a total height of 20 feet and an offset of 10 feet. The vent will be B-vent from the draft hood to the termination. The minimum size of vent should be ____.

A

3”

46
Q

A gas fan assisted 100,000 btu appliance is installed. The vent height is 15 feet. The offset is 5 feet. The venting will be single wall metal connector from the furnace outlet to the B-vent common vent. The minimum size vent pipe allowed is ____.

A

4”

47
Q

A fan assisted 120,000 btu natural gas boiler using single wall metal connector in a basement with a total vent height of 20 feet and offset of 5 feet requires a minimum ____ type B double wall vent.

A

4”

48
Q

A gas venting system using Type B double wall vent for both the main vent and the connectors serving an 80,000 btu fan assisted furnace and a 40,000 btu natural draft water heater with a 10-foot vent height would require a minimum ____ common vent.

A

5”

49
Q

A residential home with gas appliances has a 40,000 btu natural draft water heater using a single wall connector and an 80,000 btu fan assisted furnace. The B-vent has a total height of 20 feet with no offsets. The common vent must be a minimum ____ B-vent.

A

5”

50
Q

A residential home with gas appliances has a 40,000 btu natural draft water heater using a single wall connector and an 80,000 btu fan assisted furnace. The B-vent has a total height of 20 feet with no offsets. The water heater connector has a 2-foot connector rise. The minimum size of the connector must be ____ single wall pipe.

A

4”

51
Q

A residential home with gas appliances has a 40,000 btu natural draft water heater using a single wall connector and an 80,000 btu fan assisted furnace. The B-vent has a total height of 20 feet with no offsets. The water heater connector has a 1-foot connector rise. The minimum size of the connector must be ____ single

A

4”

52
Q

Where the vent connectors for gas appliances are combined prior to entering the vertical portion of the common vent to form a common vent manifold, the size of the common vent shall be reduced ____%

A

10

53
Q

Each additional elbow in a gas vent greater than 45 degrees and including 90 degree elbows require an additional ____ reduction in the venting tables.

A

10%

54
Q

Listed corrugated metallic chimney liner systems for gas appliances shall be sized as B-vent and capacity reduced ____%.

A

20

55
Q

Ducts shall not be attached to a ____.

A

wall furnace

56
Q

Where a gas dryer vent exhaust duct equivalent exceeds ____ feet, the equivalent length of the exhaust duct must be identified on a permanent label or tag located within ____ feet of the exhaust duct location.

A

35,6

57
Q

Gas water heaters shall be tested in accordance with ____ and ____.

A

ANSI Z21.10.1, ANSI Z21.10.3

58
Q

Gas boilers shall be listed to ____ or ____ standards.

A

ANSI Z21.13, UL795