Coil Operation QUESTIONS WITH
CORRECT ANSWERS ALREADY
PASSED
To prevent freezing of downstream equipment in a coil handling a large amount of outdoor air,
which of the
following is required?
a) A long coil length
b) A vacuum breaker
c) A preheat coil
d) An oversized coil
e) Two-position damper motor - correct answer ✔✔ c
It is good practice to select steam coils which require at
least 40% of coil capacity when air temperature is 1 degree C for which of the following
reasons?
a) Steam flow is high enough at high temperature and
prevents build-up and freezing of condensate
,b) The load on the circulating fan is kept from overheating
c) The mixing valve will never cut out if capacity stays
above 40%
d) To avoid hot condensate splashing
e) None of the above - correct answer ✔✔ a
Steam coils with a short tube length of 1.1 m or less
a) are more likely to freeze, even if the steam trap is
properly chosen
b) are not recommended because they are more likely to freeze
c) are more likely to freeze, even if the coil is properly
piped and sloped
d) are less likely to freeze if the steam trap is properly
chosen and the coil is properly piped
e) are less likely to freeze regardless of steam trap choice and coil piping - correct answer ✔✔ d
Steam coils with long tube lengths
, a) have the greatest freezing problems at extremely low
temperatures such as -35 degrees C
b) have the greatest freezing problems at temperatures of
about -2 to -1 degrees C
c) have freezing problems at any temperature
d) are not likely to freeze at any temperature
e) are less likely to freeze than steam coils with short
tube lengths - correct answer ✔✔ b
Freezing problems in steam coils with long tube lengths,
handling a large amount of low temperature outside air
a) are minimized by using preheat coils controlled by an
outdoor temperature controller
b) are minimized by using modulating control valves to
control the steam heating coil output
c) are best minimized by using a two-position control valve
to control coil output
d) are minimized by using an oversized coil
CORRECT ANSWERS ALREADY
PASSED
To prevent freezing of downstream equipment in a coil handling a large amount of outdoor air,
which of the
following is required?
a) A long coil length
b) A vacuum breaker
c) A preheat coil
d) An oversized coil
e) Two-position damper motor - correct answer ✔✔ c
It is good practice to select steam coils which require at
least 40% of coil capacity when air temperature is 1 degree C for which of the following
reasons?
a) Steam flow is high enough at high temperature and
prevents build-up and freezing of condensate
,b) The load on the circulating fan is kept from overheating
c) The mixing valve will never cut out if capacity stays
above 40%
d) To avoid hot condensate splashing
e) None of the above - correct answer ✔✔ a
Steam coils with a short tube length of 1.1 m or less
a) are more likely to freeze, even if the steam trap is
properly chosen
b) are not recommended because they are more likely to freeze
c) are more likely to freeze, even if the coil is properly
piped and sloped
d) are less likely to freeze if the steam trap is properly
chosen and the coil is properly piped
e) are less likely to freeze regardless of steam trap choice and coil piping - correct answer ✔✔ d
Steam coils with long tube lengths
, a) have the greatest freezing problems at extremely low
temperatures such as -35 degrees C
b) have the greatest freezing problems at temperatures of
about -2 to -1 degrees C
c) have freezing problems at any temperature
d) are not likely to freeze at any temperature
e) are less likely to freeze than steam coils with short
tube lengths - correct answer ✔✔ b
Freezing problems in steam coils with long tube lengths,
handling a large amount of low temperature outside air
a) are minimized by using preheat coils controlled by an
outdoor temperature controller
b) are minimized by using modulating control valves to
control the steam heating coil output
c) are best minimized by using a two-position control valve
to control coil output
d) are minimized by using an oversized coil
