Chapter 2 Flashcards
Radiators are constructed in such a manner as to prevent a _______ to radiate heat from the steam or hot water contained in the radiator.
a. Small internal volume
b. Large surface area
c. Pleasant appearance
d. Smaller area
B
Packless radiator valves have a blank diaphragm that completely seals off the valve body to prevent steam from leaking out around the valve stem.
A. Copper
B. Bronze
C. Lead
D. Steel
B
The exhaustor consists of a series of blanks through which water is forced by the vacuum pump
A. Nozzles
B. Venturis
C. Orifices
D. Pipes
A
The air vent consists of a small housing containing a sealed cylinder partially filled with blanks.
A. Volatile liquid.
B. Water.
C. Steam.
D. Compressed air.
A
A steam system air vent consist of
a)A ball float
b)A cylinder filled with air
c)A cylinder filled with a volatile liquid
d)A cylinder filled with a hygroscopic discs
c
A vacuum pump in a steam heating system has two main functions:
a)reduce back pressure in the condensate piping and reduce pressure in the steam mains
b)reduce back pressure in the condensate piping and return condensate to the boiler
c)reduce pressure in the steam mains and return condensate to the boiler
d)reduce the water level in the expansion tank and return condensate to the boiler
b
The presence of _____________ in a steam system is undesirable since it blocks the free flow of steam, reduces heat transfer, and promotes corrosion
a)Gylcol
b)Air
c)Total Dissolved Solids (TDS)
d)Hot water
b
Using a vacuum pumped condensate system is an alternative to _____________
a)Using higher steam supply pressure
b)Using pneumatic return
c)Using hot water hot supply
d)Using condensate return
a
A pumped-return condensate receiver is always vented to atmosphere.
True False
true
_________ have largely replace the cast-iron radiator in modern installations
a)Convectors
b)F&T Traps
c)Unit ventilators
d)Unit heaters
a
A wall convector will not circulate heated air if the cabinet cover rests on the flooring
True False
true
Unit ventilators are
a)installed in large central air handling units
b)equipped with fresh air inlet dampers and air filters
c)natural draft appliances
d)ceiling hung to provide heat to large spaces
b
Adding a blower to a convector results in
a)A unit heater capable of large heat output for a fairly small unit
b)A unit heater with large radiant heating surface
c)A unit heater that that must rest on the floor to provide heat effectively
d)Allows the unit heater to operate at negative pressure
a
Radiators and convectors should be placed on outside walls, under windows where possible so that:
a)air filtration takes place
b)there are no water hammer issues
c)maintenance personnel can find them
d)cold infiltration air mixes with warm air to prevent drafts
d
