Power Engineering 5th class book 2
Questions and Verified Answers
External heat gains include those by: - ANS Infiltration, Ventilation and Solar radiation
A wind velocity of _______________ is used to calculate the winter infiltration heat
loses - ANS 24 km/h ( 15mph )
A
The heat given off by light fixtures is not greatly affected by the: - ANS Room
temperature
VI
Heat loses through large, single pane window sections are ________________ double
pane windows, which have the space between the panes filled with argon - ANS
TU
significantly greater than
The amount of heat lost by conduction, convection, radiation, and infiltration is directly
affected by the - ANS wind velocity
IS
Radiators are constructed in such a manner as to present a ______________________
to radiate heat from the steam or hot water contained in the radiator - ANS large
OM
surface area
Packless radiator valves have a __________________ diaphragm that completely seals
off the valve body to prevent steam from leaking out around the valve steam - ANS
bronze
NA
The exhauster consists of a series of ________________ through which water is forced
by the vacuum pump - ANS nozzles
JP
The air vent consists of a small housing containing a sealed cylinder partially filled with
_______________________ - ANS volatile liquid
In a gravity return system, the boiler should be placed - ANS well below the lowest
radiator
A pressure balancing device that prevents the boiler pressure from forcing the water in
the boiler into the return line is called a - ANS Hartford loop
, If the water level falls too low during operation of a steam heating boiler, the operator
should - ANS shut the boiler down
Steam in a two-pipe, vacuum return system is supplied at a maximum pressure of
_______________________ - ANS 103 kPa ( 15psi)
Cause of insufficient steam supply to the heating units can be attributed to - ANS
Improper pitch, Defective radiator valve, Clogging of connections and valve
Special diverter fitting are required in ________________ to ensure an adequate flow of
A
water each convector - ANS One-pipe hot water systems
VI
With the pump running in a hot water heating system, the normal differential pressure
between the suction and discharge is _______________ - ANS 55 kPa ( 8psi)
TU
Which of the following should be included in the routine operation of a hot water heating
system - ANS Testing the controls and safety relief valve on a regular basis, keeping
the boiler room and boiler clean and tidy, refer periodically to the boiler manufacturer's
operation instructions
IS
If there is an air lock after repairs have been made on the piping system, the operator
should - ANS open the system vent valves, or check operation of the automatic air
OM
venting system
Which is the following are advantages of a warm air heating system - ANS A more
uniform temperature distribution can be obtained due to a positive air circulation, filters
may be used to clean the air, controlled amounts of external ventilation may be drawn
NA
into the system
What is the name given to the furnace type that has the return air enter the top and the
supply air leave the bottom of the system - ANS Downflow furnace
JP
The flue gas temperature on the heat exchanger exit of a warm air furnace is about
_______________ - ANS 230°C (450°C)
The air blower used in a forced warm-air furnace is usually driven by - ANS An electric
motor via a V-belt connected to a fixed pulley mounted on the blower shaft
Which of the following are types of air distribution systems - ANS Extended plenum,
Perimeter loop, Perimeter radial
Questions and Verified Answers
External heat gains include those by: - ANS Infiltration, Ventilation and Solar radiation
A wind velocity of _______________ is used to calculate the winter infiltration heat
loses - ANS 24 km/h ( 15mph )
A
The heat given off by light fixtures is not greatly affected by the: - ANS Room
temperature
VI
Heat loses through large, single pane window sections are ________________ double
pane windows, which have the space between the panes filled with argon - ANS
TU
significantly greater than
The amount of heat lost by conduction, convection, radiation, and infiltration is directly
affected by the - ANS wind velocity
IS
Radiators are constructed in such a manner as to present a ______________________
to radiate heat from the steam or hot water contained in the radiator - ANS large
OM
surface area
Packless radiator valves have a __________________ diaphragm that completely seals
off the valve body to prevent steam from leaking out around the valve steam - ANS
bronze
NA
The exhauster consists of a series of ________________ through which water is forced
by the vacuum pump - ANS nozzles
JP
The air vent consists of a small housing containing a sealed cylinder partially filled with
_______________________ - ANS volatile liquid
In a gravity return system, the boiler should be placed - ANS well below the lowest
radiator
A pressure balancing device that prevents the boiler pressure from forcing the water in
the boiler into the return line is called a - ANS Hartford loop
, If the water level falls too low during operation of a steam heating boiler, the operator
should - ANS shut the boiler down
Steam in a two-pipe, vacuum return system is supplied at a maximum pressure of
_______________________ - ANS 103 kPa ( 15psi)
Cause of insufficient steam supply to the heating units can be attributed to - ANS
Improper pitch, Defective radiator valve, Clogging of connections and valve
Special diverter fitting are required in ________________ to ensure an adequate flow of
A
water each convector - ANS One-pipe hot water systems
VI
With the pump running in a hot water heating system, the normal differential pressure
between the suction and discharge is _______________ - ANS 55 kPa ( 8psi)
TU
Which of the following should be included in the routine operation of a hot water heating
system - ANS Testing the controls and safety relief valve on a regular basis, keeping
the boiler room and boiler clean and tidy, refer periodically to the boiler manufacturer's
operation instructions
IS
If there is an air lock after repairs have been made on the piping system, the operator
should - ANS open the system vent valves, or check operation of the automatic air
OM
venting system
Which is the following are advantages of a warm air heating system - ANS A more
uniform temperature distribution can be obtained due to a positive air circulation, filters
may be used to clean the air, controlled amounts of external ventilation may be drawn
NA
into the system
What is the name given to the furnace type that has the return air enter the top and the
supply air leave the bottom of the system - ANS Downflow furnace
JP
The flue gas temperature on the heat exchanger exit of a warm air furnace is about
_______________ - ANS 230°C (450°C)
The air blower used in a forced warm-air furnace is usually driven by - ANS An electric
motor via a V-belt connected to a fixed pulley mounted on the blower shaft
Which of the following are types of air distribution systems - ANS Extended plenum,
Perimeter loop, Perimeter radial
