Lvl.4 Final Gas Review Flashcards
LP Gases include propane and butane. True or False?
True
CV of natural gas is 0.293kw/ft3. True or False?
True
Calorific value or a butane/air mixture would be _______3200btu/ft
a) greater
b) equal
c) less than
c) less than because added air decreases CV
When LP gases are used, the appliance manifold pressure is usually 11” w.c. True or False?
True
What is commonly referred to as the silent killer?
CO
Processed natural gas with all the heavier hydrocarbons removed is sometimes referred to as?
a) wet gas
b) dry gas
c) sour gas
d) sweet gas
b
“Air required for satisfactory combustion of gas, including excess air”
a) combustion air
b) total air
c) ventilation air
d) dilution air
a
“Mechanical draft produced by a device downstream from the combustion zone of an appliance”
a) induced
b) forced
c) assisted
d) non-natural
a)
“A burner in which combustion air is supplied by a mechanical means such as a fan or blower at sufficient pressure to overcome the resistance of the burner and the appliance”
a) induced draft
b) forced draft
c) assisted draft
d) non-natural draft
b
When conflict exists between manufacturers instructions and the code book, whose instructions should the installer follow?
code book
Local gas inspector is responsible for ensuring appliance is in safe working order and complies to code regulations. True or False?
False
The _________ is responsible for making sure the home owner knows how to start, stop, operate appliance?
installer
Gas appliance replacement parts should
a) exceed original parts specs
b) meet or exceed original part spec
c) never meet or exceed
b
Installation of a used appliance
a) prohibited
b) requires approval by authority
c) inspected and approved by installer
c
Minimum service clearance for an appliance is 24”. True or False?
True
Hose connected to a portable appliance shall not be longer than
a) 40ft
b) 30ft
c) 25ft
d) 10ft
b
Test gauge shall have a minimum diameter of
a) 1”
b) 2”
c) 2.5”
d) 3”
d
Unless specified, a gravity warm air furnace high limit should not be set higher than
a) 550f
b) 450f
c) 350f
d) 250f
c
Unless specified, a forced air furnace high limit shall not be set higher than
a) 350f
b) 250f
c) 212f
d) 180f
b
Incinerators shall be equipped with
a) no barometric damper
b) single acting barometric
c) double acting barometric
b
Water heater, unless direct vented, shall not be installed in a
a) basement
b) carport
c) bathroom
d) mechanical room
c
Natural gas systems using copper tubing must be joined with forged brass nuts
a) true
b) false
a
Tubing used in gas piping systems must be supported
a) 6ft
b) 8ft
c) 12ft
a
B fitter may work on piping system upstream of gas company meter
a) true
b) false
b
In a commercial building, piping must be identified at intervals not exceeding
a) 20ft
b) 10ft
c) 6 ft
d) 3ft
a
SCH40 Black iron is limited to what pressure if using threaded joints?
a) 250psig
b) 125psig
c) 60psig
d) 20psig
125psig
Unless approved by authority, pipe joints must be welded if nominal pipe size exceeds
a) 1.5”
b) 2”
c) 2.5”
d) 3”
b
Copper or steel tubing may be
a) flared
b) brazed
c) flared or brazed
d) neither flared or brazed
c
Minimum length of dirt or drip pocket
a) 6”
b) 4”
c) 3”
d) 2”
c
Thread compound shall not be applied to
a) first thread
b) first two threads
c) first 6 threads
b
Joining polyethylene pipe to steel pipe requires the use of
a) approved transition fitting
b) quick-disconnect fitting
c) seismic relief
d) POL
a
Max diameter of a drip or dirt pocket
a) 6”
b) 4”
c) 3”
d) 2”
d
Underground piping must be buried a minimum of
a) 36”
b) 24”
c) 15”
c
Threaded pipe connections are allowed underground. True or False?
False
Piping, hose, and fittings used in a natural gas install shall be rated for a minimum 1.5 times the max operating pressure
a) true
b) false
True
Copper tubing installed in a residential building shall be identified by yellow bands or paint at intervals not exceeding
a) 6ft
b) 8ft
c) 12ft
d) 20ft
a
pressure relief for all portable propane cylinders is?
375PSIG
Portable propane cylinder must undergo physical examination every time it is filled. True or False?
True
Portable propane cylinder relief valve must be decertified or replaced every?
a) year
b) 2 years
c) 5 years
d) 10 years
d
Portable cylinder must not be filled more than ___% of its rated volume
80%
Portable cylinder must not be filled more than ___% of its rated weight
42%
Underground steel gas piping containing liquefied propane must be schedule
a) 40
b) 80
c) 20
b
Gas fitter may reduce amount of gas going into the appliance by moving the orifice spud closest to he burner nozzle. true or false?
true
When compared to an orifice with a k factor of .9, an orifice with a k factor of .8 will pass more gas?
true
Orifices are usually made of brass or aluminum. True or False?
True
Construction rental heaters are designed to be run on nat gas or propane and equipped with
a) fixed orifice
b) universal
c) adjustable
d) one
b