CH.115
An advantage of low voltage switching is:
A )
that local and remote control of lights is permitted
B )
the wiring does not require conduits
C )
changes are simple and economical
D )
a and b are correct
E ) a, b and c are correct
The life safety code requires that
emergency lighting be provided for means of exit in:
A )
places of assembly of less than 300 people
B )
all occupied spaces indoors
C )
all multiple residence units
D ) all educational and
institutional occupancies
E )
office buildings with occupancies of 300 or more people
When designing a lighting system which of
the following should be considered?
A )
initial cost
B )
operating cost
C )
maintenance cost
D ) all of the above
E )
none of the above
Most dimmer switches sold today:
A )
divert some current through a variable resistor
B )
can be used with incandescent or fluorescent lighting
C ) save most of the power not
being used by the luminaire
D )
can control the lighting level from 0 - 100%
E )
are not cost effective as energy savers
Direct lighting systems:
A )
have a higher initial cost than indirect lighting
B )
have greater glare control
C ) are more energy efficient
than indirect lighting
D )
produce shadow free light
E )
blend with the environment
In large buildings approximately what
percentage of the electrical load is lighting?
A ) 60%
B )
65%
C )
70%
D )
75%
E )
80%
When control for multiple locations is
required:
A )
a 4-way switch is used
B )
an off-on switch is used
C )
two 2-way switches are used
D )
three or more one-way switches are used
E ) two 3-way switches and two
4-way switches are used
A luminaire is a:
A )
type of light reflector
B )
type of light refractor
C )
lamp ballast
D ) complete lighting unit
E )
type of lamp
Ambient lighting, can be improved by two
types of lighting:
A ) direct and indirect
B )
natural and artificial
C )
fluorescent and incandescent
D )
reflective or refractive
E )
general or local
Occupancy sensors are:
A )
semi-automatic switches
B )
self-regulating switches
C ) automatic switches
D )
modulating switches
E )
packaged switches
CH.116
The backflow prevention method which
consists of two independently acting check valves with an automatic operating
pressure differential relief valve located between the two check valves is
called:
A )
air gap backflow prevention
B )
double check valve
C ) reduced pressure principal
device
D )
atmosphere vacuum breaker
E )
PVB
Which of the following statements about a
constant pressure system with Pneumatic Tank is false?
A )
Water entering directly into the pump suction is discharged into
pressurised tank.
B ) This system is primarily
used in larger buildings.
C )
A system controller automatically starts a standby pump in the event of
pump failure.
D )
The system has a pressure regulator to maintain a relatively constant
pressure above the water level inside the tank.
E )
Air must continuously be introduced into the tank.
When the maximum building demand for water
is always less than the maximum flow available from a municipal or local
distribution system which of the following systems can be used?
A )
A constant pressure system with suction tank
B )
A constant pressure system with pneumatic tank
C ) Tankless constant pressure
system
D )
A downfeed system
E )
A gravity system
In a circulating hot water system automatic
air vents serve which of the following functions?
A )
They cool the water in the storage tank to increase the temperature
differential to increase circulation.
B ) They remove air that is
released when water is heated.
C )
They supply air to cooling water in the storage tank.
D )
They are required for adequate water aeration.
E )
None of the above.
The system, which has a storage tank above
the highest fixture in the system, is called:
A )
an upfeed system
B )
a constant pressure system with suction tank
C )
a tankless constant pressure system
D ) a downfeed system
E )
a direct pressure system
Which of the following is not an element
found in a circulating hot water system?
A ) A fire recoil element
B )
Air vents
C )
Heaters
D )
Backflow valves
E )
Return Piping
Which of the following statements about
pressure relief valves is false?
A )
The valve may be installed anywhere in the hot water system close to the
heater or tank.
B ) The valve must be directly
connected to a drain or vent pipe.
C )
The valve is opened by pressure in the line surpassing a preset pressure
set on the spring in the valve.
D )
The valve is automatically closed when the water line pressure drops
below the spring pressure setting.
E )
None of the above.
Temperature relief devices are effective in
eliminating the following problem:
A )
scale build-up in the system
B ) flashing of water into
steam when faucets are opened
C )
venting off air released from water during heating
D )
inadequate heating of the water
E )
water stagnation
Which of the following statements about
Non-Circulating hot water systems is true?
A )
The systems have a return line.
B )
The systems are used in large residential buildings.
C )
The systems eliminate hot water stagnation.
D )
The systems contain a differential fire recoil element.
E ) The systems force large
amounts of water to be wasted before hot water is available in each fixture.
In a circulating hot water system the
municipal distribution systems and/or local storage tanks are used for which of
the following reasons.
A )
Cold water supply only
B ) Water supply to heaters
only
C )
Hot water supply from municipal heating stations
D )
Both cold water and heater water supply
E )
Water meter rationing
CH.117
The blow off valve in a storage heater is
used to:
A )
eliminate pressure build-up in the heater.
B )
monitor unsafe temperatures.
C )
release steam should the heater malfunction to avoid flashing of steam
in the fixtures.
D ) remove sediment carried to
the heater through the water line.
E )
shut off the flow of gas if the flame and pilot light are extinguished.
Corrugations in outside aluminium sheet
metal conductors is required to:
A )
increase flow speed of storm water.
B )
decrease potential for blockage.
C )
eliminate corrosion.
D )
allow water flow if there is scale build-up.
E ) permit expansion.
What is the correct sequence, from start to
finish, needed to replace a washer in a faucet? 1) Unscrew the packing nut and
remove the spindle. 2) If the valve seat is smooth and serviceable, replace the
spindle and tighten the packing nut. 3) Remove the washer from the end of the
spindle. 4) Shut off the water at the nearest isolation valve. 5) Place the new
washer on the end of the spindle.
A )
1, 2, 3, 4, 5
B ) 4, 1, 3, 5, 2
C )
5, 4, 3, 2, 1
D )
4, 1, 5, 2
E )
5, 2, 1, 4,
Which of the following has a trap as an
integral part of the fixture?
A ) water closet
B )
sink
C )
storm drain
D )
sewer
E )
sump pump
Which of the following statements about
footing drains is true?
A )
Installed to prevent an accumulation of groundwater around the building
foundations.
B )
Used to reduce the hydrostatic pressure on the walls below ground level.
C )
Perforated or porous pipe is used to collect the water near the footings
D )
The collected water is drained to a remote area or into a sump.
E ) All of the above
Which of the following statements is true?
A )
Branch line connections to the waste stack should be connected at an
angle of more than 45 degrees.
B )
The stack vent prevents sewer gas from being vented through the roof.
C ) The stack vent and loop
vents allow equalisation of pressure in the system.
D )
In multi-story buildings one stack is used for venting and waste
disposal.
E )
Most buildings have several waste and soil stacks with each stack
providing drainage for all the sections of the building.
Drain traps serve which of the following
purposes: 1) to seal the outlet fixture 2) to prevent backflow of sewer gas 3)
to deflect grease and oil for separate disposal
A )
2 only
B )
1 only
C )
both 1 and 3
D ) both 1 and 2
E )
1, 2 and 3
Sewer smells coming from a floor drain in a
washroom can be a problem if the floors of the washroom are not cleaned often.
Which of the following courses of action is the simplest way to stop the smell
from coming out of the drain?
A ) Pour a pail of water in
the drain.
B )
Cover the drain opening.
C )
Sanitise the washroom.
D )
Flush the drain with caustic soda.
E )
Improve the washroom's ventilation.
The pounding or banging of pipes and
shuddering of fixtures caused by a shock wave resulting from a sudden stop of
water flow in a pipe results in which of the following sounds?
A )
chattering of faucets
B )
whistling of faucets
C ) water hammer
D )
hissing in the pipes
E )
creaking of the pipes
Negative pressure in a drainage system may
result in which of the following problems?
A )
clogging of drain pipes
B )
scale of build-up in water closets
C ) drawing out of sealing
liquids in traps
D )
forcing of sewer gases through traps
E )
collection of sediment in drain traps
CH.118
The heat used to change the state of a
substance, is called:
A )
superheat
B )
convection heat
C )
sensible heat
D )
conduction heat
E ) latent heat
The rate at which a system will remove heat
from the refrigerated medium is defined as:
A )
coefficient of performance
B )
net refrigerating effect
C ) refrigeration capacity
D )
compression ratio
E )
differential efficiency
Refrigerant mediums will evaporate:
A )
when pressure is increased
B ) when temperature is
increased
C )
when they are diluted
D )
when temperature is decreased
E )
when heat is removed
In the case of a simple ice box which of
the following heat transfers is correct?
A )
Air loses latent heat, ice does not gain any heat.
B )
Air loses sensible heat, ice does not gain any heat.
C )
Air loses sensible heat, ice gains sensible heat.
D ) Air loses sensible heat,
ice gains latent heat.
E )
Air loses latent heat, ice gains latent heat.
Which column in the refrigerant table lists
the absolute pressure in kPa?
A )
Column 1
B ) Column 2
C )
Column 3
D )
Column 4
E )
None of the above
The function of the condenser is to:
A )
vapourise the liquid refrigerant
B ) change high pressure
refrigerant vapour to liquid
C )
pressurise low pressure refrigerant vapour
D )
vent off vapourised refrigerant
E )
lower the liquid refrigerant pressure
Which of the following statements about
low-side pressure and temperature is false?
A ) The evaporation
temperature of the refrigerant should be 5 - 10 °C higher than that of the
cooled medium.
B )
For a given amount of heat transfer an oversized evaporator can be
operated at a higher temperature.
C )
The low side pressure depends on the type of evaporation used.
D )
The evaporation temperature of the refrigerant will be higher if the
evaporator lowers the refrigerant pressure.
E )
All of the above.
Which of the following statements about
high-side pressure and temperature is true?
A )
The heat flow is from the cooling medium to the hot refrigerant.
B ) The condensing temperature
of the vapour is 15 - 20 °C higher than the temperature of the medium used in
the condenser.
C )
The condensation temperature of the refrigerant will be lower if the
pressure of the vapourised refrigerant is lowered.
D ) The condenser functions by taking latent heat
from the surrounding air and adding it as sensible heat to the refrigerant.
E )
None of the above
In the vapour compression type of
refrigeration system, the liquid refrigerant is changed to a gas in the:
A )
condenser
B )
charging drum
C )
receiver
D )
compressor
E ) evaporator
The two major types of refrigerating
systems are:1. direct2. ammonia 3. indirect 4. Freon
A )
1, 4
B )
2, 3
C )
2, 4
D ) 1, 3
E )
3, 4
CH.119
Ammonia refrigerants:
A )
have high sensible heat capacity
B )
mix well with oil
C )
are very expensive
D ) are well suited for
industrial refrigeration
E )
are ideally suited to copper piping systems
The property which has to be known for the
calculation of the size of control valve and piping etc, is:
A )
specific volume
B )
enthalpy
C )
refrigerating effect
D ) density
E )
boiling point
Freon 22 refrigerant:
A )
is not miscible with oil
B )
is mostly used in packing plants
C )
is corrosive on copper
D )
is corrosive on aluminium
E ) is a heat transferring
medium
R-22 (Freon-22) is nontoxic and
nonflammable. Which group does it belong to?
A )
Group A2
B )
Group B4
C ) Group A1
D )
Group A3
E )
Group B2
The refrigerant R-11 belongs to the
following group:
A )
group "A2"
B )
group "B1"
C )
group "A3
D )
group "2B"
E ) group "A1"
A )
moisture reaction
B )
enthalpy
C )
density
D )
leakage tendency
E ) miscibility
The refrigerant with the highest
refrigerating effect per kg of any refrigerant is:
A )
propane
B ) ammonia
C )
carbon dioxide
D )
Freon-22
E )
water
Which of the following
characteristics is common in all of the group B refrigerants?
A ) High toxicity
B )
High flammability
C )
Average Flammability
D )
Low Toxicity
E )
Low flammability
The standard refrigeration cycle is used to
compare refrigerants and machines operating under comparable conditions. These
standard conditions are:
A )
1030 kPa and atmospheric pressure
B ) 30 °C condensing and -15
°C evaporating
C )
30 kPa and atmospheric pressure
D )
-30 °C condensing and 15 °C evaporating
E )
30 kPa and atmospheric temperature
Freon:
A ) is non-toxic
B )
has a strong odour
C )
is explosive when mixed with air
D )
is highly toxic
E )
is prohibited to be used as a refrigerant
CH.120
Which of the following is NOT a component
of the low pressure side of the system?
A ) compressor discharge
B )
evaporator
C )
downstream side of the regulating valve
D )
medium to be cooled
E )
all of the above
The temperature in the evaporator:
A )
depends on pressure in the receiver
B )
will decrease when the compressor stops
C ) depends on the pressure in
the evaporator
D )
depends on the ambient temperature
E )
is controlled by the charging valve
A compression refrigeration system can be
divided into two parts; a high pressure section carrying the head pressure and
a low pressure section carrying the ___________ pressure.
A )
discharge
B )
back
C )
hot
D )
return
E ) suction
Raising the condensing point (saturation temperature)
of the refrigerant vapour above the temperature of the cooling medium is the
function of the:
A ) compressor
B )
condenser
C )
evaporator
D )
absorber
E )
refrigerant
The primary difference between direct and
indirect refrigeration systems is the:
A )
type of heat transfer medium
B )
type of refrigerant
C )
evaporator pressure
D )
compressor location
E ) evaporator location
A purpose of a liquid refrigerant control
or regulating valve is:
A )
to drain the receiver
B )
to regulate the refrigerant flow to the evaporator
C )
to maintain a constant level in the receiver
D )
to regulate the cooling water to condenser
E ) to isolate the high side
from the low side
The brine pump:
A )
circulates the refrigerant through the evaporator
B )
pumps brine through the condenser cooling circuit
C ) circulates the brine
through the cooling circuit
D )
maintains the brine level in the cooling circuit
E )
is used to remove heat from the condenser
In actual systems there will be a gradual
pressure drop through each side of the system due to:
A )
the economiser
B ) friction in the
evaporator, condenser, and piping
C )
decomposition of refrigerants
D )
coefficients of expansion of system components
E )
superheating effects
Which of the following is NOT an advantage
of a factory assembled packaged refrigerant?
A )
Components are designed to match each other.
B ) Parts can be ordered and
installed separately.
C )
The unit is more compact.
D )
Space requirements are minimised.
E )
The unit is equipped with all the required auxiliary equipment.
The heat given up by the brine in the
evaporator, must equal the heat:
A )
picked up by the receiver
B )
produced by the compressor
C )
given up by the condenser
D )
gained by the condenser
E ) picked up by the
refrigerant
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