ABSA 5th Class Practice Exam – All Questions

Browse all practice questions for the ABSA 5th Class Practice Exam. Search by topic, open any question and review its full explanation, then test yourself in the practice quiz.

Start practice test Flash cards

How a two-pipe direct return hot water system works and why it uses separate supply and return pipesHow does a two-pipe direct return hot water system typically function?Safety first: before welding a power engineer must isolate equipment and clear combustiblesBefore any welding can take place in one of his/her vessels, what must a power engineer ensure?To raise the control temperature of a self-regulating valve, adjust the spring compressionTo increase the control temperature of a self-regulating valve, what needs to be adjusted?

More practice questions

These questions are part of the practice quiz. Start practicing

What type of flame is indicative of incomplete combustion in gas burners?
In the case of a simple icebox, what occurs between air and ice?
What grade of oil is most commonly used for domestic and small commercial boilers?
Which type of humidifier breaks water up into a mist or fog?
Which type of brine is commonly used for skating and hockey rink refrigeration systems?
To what level should the bearing housing of an electric motor be filled with oil?
Where should steam traps be installed within a system?
How can an operator check if a boiler safety valve will open at its set pressure?
What is the most commonly used refrigerant control system that consists of a bellows or diaphragm?
What document is issued to a welder upon qualification for a welding procedure?
What is a common issue that can affect condenser operation?
Which of the following are causes of pressure explosions?
What should be done immediately after taking a potable water sample for testing?
Which of the following best describes the purpose of exhaust fans in cooking areas?
What happens to relative humidity when the air temperature increases without adding moisture?
What does a tensile test measure in weld testing?
The efficiency range of a pulse combustion furnace is:
What do tables for varying wall thickness of pipe typically provide?
What is a critical consideration when selecting materials for pipes?
A weld made from both sides of the joint between two pieces of metal is referred to as what?
In a refrigeration system, what role does latent heat play?
Which water distribution system is used for high demand and insufficient pressure on upper floors?
How do pot feeders operate in relation to chemical injection?
What can excess pressure in a pipe system lead to?
What does the term 'latent heat' refer to in refrigeration?
What is carbon that is not combined with hydrogen referred to as?
How do high efficiency fluorescent ballasts aid in energy conservation?
In what applications are copper and copper alloys commonly used?
How can you confirm that you've added sufficient refrigerant to a new system?
What should be done if the welding method is not qualified under the applicable code?
If a compressor fails to start while the motor is operational, what could be a likely cause?
What happens to elemental impurities during the regeneration of a sodium zeolite softener?
In a hardness test on feedwater, what color indicates the presence of hardness?
How many personal locks are typically issued to an employee?
What is the latent heat of fusion of water at 0 °C?
In high efficiency furnaces, if the flue gas temperature drops below 65 degrees C, what happens?
What is the purpose of a condenser in a refrigeration system?
What is the standard voltage for an internal combustion engine generator set starting system?
How many valves are typically present in a toilet flush tank?
What can result from scale and sludge build-up in a boiler?
What does a higher draft reading in a furnace generally indicate?
Which of the following contributes to the lifespan advantages of fluorescent lighting?
In a high fire hazard building, how many square meters can a single sprinkler protect?
What does a hot water gravity circulation system rely on to move water through the pipes?
Which type of gas burner is commonly used in packaged boilers?
The typical supply pressure of compressed air used for starting an engine is about how many kPa?
How do pot feeders function in a boiler system?
How frequently do burner and fan motors that use standard bearings generally need lubrication?
What does a hardness test indicate in welding?
The most common oil heater combines radiant heat with which type?
What is the typical application of refrigerants in a refrigeration cycle?
What is the maximum operating temperature that should not be exceeded in hot water boiler operation?
Which of the following components can cause a furnace explosion if not managed properly?
Which chemical compounds are part of the "exchange" stage in a softener's regeneration cycle?
What is the purpose of a steam trap?
What is typically required to ensure safe operation of a piping system?
What is the operating element of an automatic sprinkler head that can be used along with a heat-sensitive bulb?
What causes draft in a boiler when produced naturally?
What is one property desirable in a refrigerant regarding environmental impact?
What allows for more uniform temperature distribution in a forced warm air furnace heating system?
What is a key characteristic of safety footwear used in welding?
What keeps a solenoid type fuel gas valve closed?
For what type of load is a capacitor start motor typically used?
What are the two main categories of manufactured pipe?
How is the synchronization of a standby generator set usually achieved?
What shape are ring joint gaskets typically in cross-section?
To achieve atomization, heavy oils must be heated to approximately how many degrees Celsius?
What is NOT a component of the refrigeration cycle?
What temperature should a thermostat automatically shut down an electric snow melting unit when the outdoor temperature exceeds?
What is the function of a fuse in an electrical circuit?
What is the minimum distance required from a furnace to an oil storage tank?
What is the primary purpose of feedwater system filters?
Which of the following is not an advantage of heat removal luminaires?
What type of compressor uses impellers to draw in vapor?
A unit heater is constructed similarly to which of the following?
What is another name for an instantaneous water heater?
What is another term that means the same as "carryover"?
What type of defects can a fluorescent penetrant test detect?
Which methods are usually used to connect pipes together?
What commonly indicates the need for backwashing a pressure filter?
What should be done if the safety relief valve is set too low?
Which component of a mechanical seal is designed to prevent axial leakage?
Which of the following could cause a flush valve on a toilet to leak?
When discussing "Relative Density," the density is compared to what substance?
What characteristic should an ideal refrigerant possess?
What is a frequent cause of serious accidents related to valves?
What is the minimum distance a fuel storage tank must be located from the furnace?
Relative humidity decreases when air temperature is lowered, without adding moisture, true or false?
Where are steam traps usually located in a steam line?
How does the inclined manometer compare to the U manometer in terms of accuracy?
Is it true that at the same pressure, the boiling point of water is equal to the condensing temperature of steam?
Which of the following describes the role of a circulating pump in a heating system?
What are the combustible components of coal?
A draft gauge on a furnace indicates the draft in what measurement?
Which of the following is considered the building block of all matter?
Is it true that Group B refrigerants have high toxicity?
When commissioning a new hot water heating system, what is the common practice to prevent larger particles from reaching the circulating pump?
What is the primary function of a gas burner?
In refrigeration, what primarily causes pressure drops across high and low pressure sides?
What is the primary function of a mechanical seal in machinery?
During the backwash cycle, what happens to the zeolite?
What condition is necessary for the combustion of fuel in a boiler furnace?
What kind of oil should be used in the bearing housing of an electric motor?
Which of the following components is necessary for proper functioning in a closed expansion tank system?
Which condition can increase the likelihood of a furnace explosion?
Which types of airborne particles can air filters in warm air heating systems trap?
What characteristic does a soldered link provide in an automatic sprinkler head?
What type of liquid is typically found in the capillary tube of a remote bulb thermostat?
Where is spot heating commonly utilized?
An anchor chair is primarily used in relation to pipes and fittings to do what?
What factors influence the condensing temperature and corresponding head pressure of refrigerant vapor?
For how long is a welder's certificate typically valid?
The TDS (total dissolved solids) test is conducted using which of the following?
What does the term "Net Refrigerating Effect" refer to?
In a refrigeration system, the presence of bubbles in the sight glass typically indicates what?
What is a critical factor for the operation of heavy oils in combustion processes?
What is one advantage of expansion bends over expansion joints?
What must a ladder have if it is intended for use?
What is typically required for successful ignition in a multi-nozzle burner?
What is a smoke detector that uses a short beam between a light source and receiver called?
Which statement is true about oil additives?
Where should heated air ideally enter rooms in a warm air heating system?
What type of pump is commonly used in hot water heating systems?
What is a modern method of removing dissolved solids from a boiler?
A valve which often contains a dashpot to cushion the action of the valve is referred to as what?
What is the main characteristic of natural draft furnace operation?
What does the upper explosive limit of a hydrocarbon refer to?
Water impurities can be counteracted using which of the following methods?
Welding together DN 50 and smaller pipe is typically done using which method?
What is required to prevent oil from spreading beyond the confines of a heater in the event of a ruptured tube?
When a gas-fired burner is operating properly, what color will the flame primarily be?
Which of the following types of bearings are commonly found in electric motors?
Which type of oil burner is utilized when oil is supplied under high pressure?
CO2 fire extinguishers are suitable for which class of fires?
Each pass of a welding rod creates what?
What type of water system uses a private supply at around 420 KPA?
What is the role of the gas burner in relation to fuel preparation?
Which of the following thermodynamic properties apply to refrigerants?
What distinguishes the SDS from the MSDS?
What is a potential hazard when working in a confined space?
What does the temperature control on a steam to hot water converter manage?
What is one bar of pressure equivalent to in the SI system?
Which is a disadvantage of hermetic type reciprocating compressors?
Ultraviolet light is primarily used to remove what from the air?
Internal suction and discharge valves are found in which type of refrigeration compressor?
What is the measure of a lamp's efficiency?
Which of the following is NOT considered a cause of furnace explosions?
How is the supply valve operated in a dry standpipe system?
A complete electrical circuit must be:
What is the primary function of flameproof gloves in welding?
In a combustion process, excess air is typically used to achieve what?
What percentage volume of natural gas is constituted by ethane?
In a microturbine, the air is compressed in which component?
What is the minimum temperature of water required for a hydrostatic test of a boiler?
What type of valve can be operated by chains in the event of a gauge glass breaking?
What is an advantage of using an atomising humidifier?
What is the role of excess air during the combustion in a boiler?
What is the name of the motor that has an extra winding in the stator for added torque?
Which method is used in weld testing to assess the durability of a weld?
What is welding flash?
What are the two types of expansion joints?
Who typically writes the SDS/MSDS documents?
In a low temperature application, how does the fin spacing in a finned evaporator compare to that in a medium temperature evaporator?
Which of the following is NOT a type of compressor seal?
What happens to the refrigerant in the condenser of a refrigeration system?
Refrigerant mediums will evaporate when?
In a hot water boiler, what is the minimum pressure differential between the operating pressure and the safety relief valve set pressure?
Why is fire a distinct possibility in hot oil systems?
What substance is known to absorb humidity inside a boiler during dry lay up?
Which backflow prevention method involves two check valves with a relief valve in between?
What could potentially cause defective condenser operation?
Which of the following best describes the role of a coupling in a compressor?
What is the importance of rehabilitation services in an emergency plan?
Which of the following is NOT a problem associated with flush valves (flushometers)?
When changing 1L of water into steam, the volume increases to how many liters?
Which factors are considered when choosing a backflow prevention method?
What should always be considered the weakest link in the electrical circuit?
What is the efficiency range of a pulse combination furnace?
What is the approximate maximum static pressure in a fuel oil line?
What does an intermittent pilot do during operation?
What causes a gradual pressure drop in a refrigeration system?
In a warm air heating system, what is the primary purpose of air filters?
What does a higher condensing pressure usually indicate about the refrigeration system?
What type of hot water circulation system is described as being difficult to balance due to variations in pipe lengths?
What is the primary function of an interrupted pilot?
If exhaust fans are not used over cooking equipment, what percentage of heat gain is considered in calculations?
Which of the following is not a component of a reciprocating refrigeration compressor?
Which of the following are the two overall types of weld testing and inspection?
Which type of helmet is commonly used in welding?
What type of water distribution system is used in high buildings with tanks at different intermediate levels?
What type of seal uses bolts to tighten its sealing element?
Why are the inlet vanes of a centrifugal refrigeration compressor closed during startup?
What makes watertube boilers generally safer than firetube boilers?
Which emergency procedure is important for providing immediate medical assistance?
How can the draft through a natural draft furnace be increased?
Which of the following conditions prevents the use of copper and copper alloy piping in power plants?
What voltage does the step-up transformer boost from 120 V to in an electric ignition system?
What is the name of the refrigerant characterized as nonflammable, odorless, and nontoxic, with a boiling point of -40.6 °C?
What are the most common types of bearings used in electric motors?
One tonne of refrigeration is equivalent to the absorption of how much heat per minute?
In which condition should CO2 fire extinguishers not be stored?
Which of the following is an advantage of using oil over coal as a boiler fuel?
To avoid start-up difficulties in cold weather, a thermal fluid must have what property?
When should combustion of fuel in a boiler furnace be performed?
What does the term 'scale' refer to in boiler conditions?
What is the pressure in a fully charged self-contained breathing apparatus?
Which of the following are principal parts in a closed cycle compression refrigeration system?
What is the approximate surface temperature of an internally fired, gas-fired infrared heater?
What is the maximum temperature of water in a gravity hot water system?
An electric motor in an air compressor with start/stop capacity control helps achieve what?
Which of the following is NOT an advantage of fluorescent lighting?
What is the purpose of ensuring a proper purge in a fuel system?
What happens when the inlet vanes of a centrifugal compressor are held in a closed position?
What is the unit of measure for a moment of force?
What do electronic filters primarily remove from the air?
In a forced draft system, how does the pressure inside the furnace compare to atmospheric pressure?
Which piping support device allows for axial movement of the pipe?
The input electrical energy arriving at the motor must be considered part of what?
An air compressor that employs start/stop capacity control must be equipped with what type of motor?
What is the primary function of the condenser in a refrigeration system?
Before admitting any steam to a steam piping system, what is imperative to ensure?
When using a halide torch detector, under what condition will it detect system leaks?
Which type of pipe joint is likely to offer better sealing capability?
What is the primary function of a centrifugal pump in a hot water heating system?
What is one requirement before welding occurs in a vessel?
What is the primary use of a manometer in heating systems?
Which type of fuse is used for ratings exceeding 30 amperes?
What is a purpose of a liquid refrigerant control or regulating valve in a refrigeration system?
Which bearing type is specifically designed to handle axial loads in addition to radial loads?
Dark, heavy clothing is a type of protective gear required in which activity?
What describes a heating device that consists of a nickel-chrome spiral resistor embedded in refractory material?
Regarding indirect lighting, which of the following statements is true as compared to direct lighting?
What is a common issue with flush valves leading to improper operation?
How many reasons can interrupt normal lighting and require emergency lighting?
Which of the following could cause a toilet's float valve to leak?
What action should an operator take if a softener has been idle for a period of time?
According to the second law of thermodynamics, heat will flow from which temperature to which temperature?
How does increasing the size of a motor affect its operation if it's oversized for the job?
What type of protective eyewear is essential for someone carrying out welding?
Which two aspects are important for safety before welding is performed?
Which gas is commonly known for being toxic and is a refrigerant?
How many basic types of evaporators exist based on operation?
What is meant by "precipitate" in the context of feedwater treatment?
Which two elements are used to control combustion air flow in a fire heater?
What type of compressor is typically used with an air atomizing burner?
A high limit control switch on a boiler typically:
What is a flushometer also known as?
What role does a coated electrode play in welding?
Which of the following statements is true regarding refrigeration chillers?
What happens to the flame when using a proper gas burner?
Which statement is true about pulse combustion furnaces?
What type of refrigeration cycle is most commonly used in household refrigerators?
Which hot water circulation system is self-balancing due to equal circuit lengths?
What indicates that a gas-fired burner is burning fuel correctly?
Why is it not recommended to use an on-off switch with steam grid humidifiers?
Which of the following are categories of air conditioning systems?
What is a mixture that has too much vapour to ignite called?
Conditions occurring within a boiler can include which of the following?
What can be said about the cooling efficiency of "shell and coil type" and "shell and tube type" condensers?
What is a method of backflow prevention that involves a separation between the potable water discharge and an open receiving vessel?
What is a benefit of using a fan in a unit heater?
What clearance should be maintained around sprinkler heads above large piles of combustible materials?
What does a penetrameter indicate in welding?
What is the term for the backflow prevention method that uses two independently acting check valves?
What does a hydrostatic test evaluate?
What could happen if a gas cylinder is dropped?
What primarily affects the heat load from people in a room?
How many basic styles of flush valves (flushometers) are there?
What is a common characteristic of soldered pipe joints?
What is the primary function of an air separator in a closed expansion tank system?
What material is most frequently employed to absorb humidity in dry laying up?
In welding, what does the result of a hardness test indicate?
What does a double weld achieve in metal bonding?
Which factors are necessary for complete combustion of a fuel?
Which of the following is essential to include in an emergency plan?
What type of air conditioning system includes multi-zone and dual duct systems?
Which of the following is an advantage of centrifugal refrigeration compressors?
Which of the following indicates a malfunction in a sodium zeolite softener?
What must be ensured when using a fuel oil line?
What is an effect of foaming in boiler conditions?
In refrigeration systems, what does an evaporator primarily do?
What is the pressure of a standard municipal water distribution system?
What is the primary function of the condenser in a compression refrigeration system?
At what speed does the centrifugal switch cut out the starter winding of a split-phase motor?
What is one way to increase draft through a natural draft furnace?
What is a disadvantage of using threads to join pipes and fittings?
What process occurs when refrigerant vapor turns into a liquid in the condenser?
What is the main purpose of a condenser in a refrigeration system?
What type of burner uses mechanical principles to atomize fuel oil?
In a burner with three fixed capacity nozzles, how are the secondary and tertiary nozzles ignited?
Why do the intermediate and high burner nozzles have higher capacities than the primary burner nozzle in a boiler burner with three fixed capacity nozzles?
What is the main issue with a poorly balanced gravity circulation system?
What is the term used to describe the amount of heat required to raise the temperature of a unit mass of a substance by 1 degree Celsius without changing its state?
What happens when an oil additive loses its effectiveness during oil use?
What is the primary purpose of a refrigeration expansion valve?
What does a Ground Fault Circuit Interrupter (GFI) compare to function properly?
What does the saturation temperature of the refrigerant in the condenser correspond to?
Sizing a larger motor than necessary leads to what issue?
What role does the evaporator play in a refrigeration system?
In a pulse combustion furnace, each explosion produces approximately how much energy in kJ?
What is the primary function of a vent damper in a warm air furnace?
Where are return air openings typically located in air distribution systems?
How is the temperature of a heated space typically maintained at the desired level?
What is the approximate efficiency range of hot oil convection heaters?
What must a manufacturer's welding method do to ensure quality?
Which of the following indicates a problem with a boiler's performance?
What can be used to overcome the disadvantages of a gravity circulation system?
How can the expansion of piping be effectively controlled?
Which of the following is considered to be the long-term refrigerant?
What is a disadvantage of using a refractory burner?
What is the ideal mechanical advantage defined as?
In a refrigeration cycle, what happens in the compressor?
What precautions should be taken to protect a potable water sample during testing?
What is the approximate maximum static pressure in a fuel oil line?
What is the term used to describe the combined modes of operation: backwash, injection, exchange, and rinse in a sodium zeolite softener?
At 100 °C, what is the latent heat of evaporation of water?
Which advantage does oil combustion have compared to coal combustion?

Subscribe

Get the latest from Examzify

You can unsubscribe at any time. Read our privacy policy