Archive for June 2018

The standard refrigeration cycle is used to compare refrigerants and machines operating under comparable conditions. These standard conditions are:

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 degrees Celsius condensing and -15 degrees Celsius evaporating
c) 30 kPa and atmospheric pressure
d) -30 degrees Celsius condensing and 15 degrees Celsius evaporating
e) 30 kPa and atmospheric temperature



Answer: B

The refrigerating effect of a refrigerant is

The refrigerating effect of a refrigerant is




a) equal to its latent heat of vaporization
b) greater than its latent heat of vaporization
c) less than its latent heat of vaporization
d) equal to its specific heat capacity
e) equal to its specific volume



Answer: A

Ammonia refrigerants

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


Answer: D

The ideal commercial refrigerant should

The ideal commercial refrigerant should



a) have a low latent heat capacity
b) have a high boiling point
c) have high condensing pressure
d) be environmentally friendly
e) be the least costly



Answer: D

What is the name of the refrigerant that has the following characteristics? It is nonflammable, odourless, nontoxic, it does not have a corrosive effect on metal if water is present and at atmospheric pressure it has a boiling point of -40.6 degrees C.

What is the name of the refrigerant that has the following characteristics? It is nonflammable, odourless, nontoxic, it does not have a corrosive effect on metal if water is present and at atmospheric pressure it has a boiling point of -40.6 degrees C.




a) Ammonia
b) Freon-22
c) Sulphur Dioxide
d) Butane
e) Propane


Answer: B

One tonne of refrigeration is

One tonne of refrigeration is




a) 13958 kJ per day
b) 100 kJ per minute
c) 233 kJ per minute
d) 13958 J per hour
e) 335 J per second



Answer: C

Refrigerant mediums will evaporate

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


Answer: B

Which of the following statements about high-side pressure and temperature is true?

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 degrees 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 vaporized 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


Answer: B

Which of the following statements about low-side pressure and temperature is false?

Which of the following statements about low-side pressure and temperature is false?




a) The evaporation temperature of the refrigerant should be 5 - 10 degrees 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.


Answer: A

The function of the condenser is to

The function of the condenser is to




a) vaporize the liquid refrigerant
b) change high pressure refrigerant vapour to liquid
c) pressurize low pressure refrigerant vapour
d) vent off vaporized refrigerant
e) lower the liquid refrigerant pressure


Answer: B

Which of the following is an example of a loss of latent heat?

Which of the following is an example of a loss of latent heat?



i) water evaporating
ii) ice melting
iii) refrigerant evaporating
iv) air cooling


a) iv only
b) iii only
c) i, iii, and iv
d) both i and iii
e) none of the above


Answer: E

In the case of a simple ice box which of the following heat transfers is correct?

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.



Answer: D

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?

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



Answer: C

What is the correct sequence, from start to finish, needed to replace a washer in a faucet?

What is the correct sequence, from start to finish, needed to replace a washer in a faucet?



i) Unscrew the packing nut and remove the spindle.
ii) If the valve seat is smooth and serviceable, replace
the spindle and tighten the packing nut.
iii) Remove the washer from the end of the spindle.
iv) Shut off the water at the nearest isolation valve.
v) Place the new washer on the end of the spindle.


a) i, ii, iii, iv, v
b) iv, i, iii, v, ii
c) v, iv, iii, ii, i
d) iv, i, v, ii
e) v, ii, i, iv, iii


Answer: B

The blow off valve in a storage heater is used to

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.


Answer: D

Which of the following statements about footing drains is true?

Which of the following statements about footing drains is true?




a) Installed to prevent an accumulation of ground water 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


Answer: E

Corrugations in outside aluminum sheet metal conductors is required

Corrugations in outside aluminum sheet metal conductors is required




a) to increase flow speed of storm water.
b) to decrease potential for blockage.
c) to eliminate corrosion.
d) to allow water flow if there is scale build-up.
e) to permit expansion.


Answer: E

Which of the following statements is true?

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 equalization 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.


Answer: C

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?

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) Sanitize the washroom.
d) Flush the drain with caustic soda.
e) Improve the washroom's ventilation.


Answer: A

Drain traps serve which of the following purposes:

Drain traps serve which of the following purposes:



i) to seal the outlet fixture
ii) to prevent back flow of sewer gas
iii) to deflect grease and oil for separate disposal


a) ii) only
b) i) only
c) both i) and iii)
d) both i) and ii)
e) i), ii) and iii)


Answer: D

Temperature relief devices are effective in eliminating the following problem:

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


Answer: B

Which of the following statements about pressure relief valves is false?

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.


Answer: B

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

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



Answer: C

In a circulating hot water system automatic air vents serve which of the following functions?

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.


Answer: B

In a circulating hot water system the municipal distribution systems and/or local storage tanks are used for which of the following reasons.

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


Answer: D

Which of the following statements about Non Circulating hot water systems is true?

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.


Answer: E

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?

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


Answer: C

Which of the following statements about a constant pressure system with Pneumatic Tank is false?

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 pressurized 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.



Answer: B

The life safety code requires that emergency lighting be provided for means of exit in

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



Answer: D

Most dimmer switches sold today

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


Answer: C

Occupancy sensors are

Occupancy sensors are




a) semi-automatic switches
b) self-regulating switches
c) automatic switches
d) modulating switches
e) packaged switches


Answer: C

An advantage of low voltage switching is

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


Answer: E

When control for multiple locations is required

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


Answer: E

Direct lighting systems

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


Answer: C

Ambient lighting can be improved by two types of lighting:

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



Answer: A

A luminaire is a

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


Answer: D
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