NYC RMO EXAM, CHAPTER 19 (Capacity
Control) questions with verified answers
19.01.) For a given application, a particular compressor is found to have a
volumetric efficiency of 72%, when operating at its design speed of 300 rpm. If
the speed is increase to 500 rpm it is most likely that the volumetric efficiency
will? Ans✓✓-Decrease
19.02.) From the following, compute the rpm of a single acting compressor. If it
has a stroke of 8" and the piston speed (velocity) is 360' feet per minute?
Ans✓✓-270
19.03.) Calculate the compressor displacement of a (2) cylinder, 6x6 compressor
operating at a speed of 400 rpm? Ans✓✓-78.5 cfm
19.04.) What would be the actual amount of vapor moved by the compressor in
the previous question if it had a volumetric efficiency of 88? Ans✓✓-70 cfm
19.05.) Calculate the maximum displacement of a (6) cylinder compressor
operating at 650 rpm. Each cylinder has a volume of 50 inches squared? Ans✓✓-
113 cfm
19.06.) If a reciprocating compressor's unloaders fail in the open position which of
the following will take place? Ans✓✓-Evaporator pressure will rise
19.07.) Clearance pockets are equipped with a small manual valve that makes it
possible to open and close the pocket. What effect does it have on the system
when it has been adjusted to the open position? Ans✓✓-The compressor moves
less vapor
19.08.) Freon compressors are sometimes equipped with magnetic cylinder
bypass valves. One of the functions of these valves is to? Ans✓✓-Starting the
compressor
19.09.) In a Freon compression system, which of the following would be
associated with a reduction in capacity? Ans✓✓-? ask professor
Control) questions with verified answers
19.01.) For a given application, a particular compressor is found to have a
volumetric efficiency of 72%, when operating at its design speed of 300 rpm. If
the speed is increase to 500 rpm it is most likely that the volumetric efficiency
will? Ans✓✓-Decrease
19.02.) From the following, compute the rpm of a single acting compressor. If it
has a stroke of 8" and the piston speed (velocity) is 360' feet per minute?
Ans✓✓-270
19.03.) Calculate the compressor displacement of a (2) cylinder, 6x6 compressor
operating at a speed of 400 rpm? Ans✓✓-78.5 cfm
19.04.) What would be the actual amount of vapor moved by the compressor in
the previous question if it had a volumetric efficiency of 88? Ans✓✓-70 cfm
19.05.) Calculate the maximum displacement of a (6) cylinder compressor
operating at 650 rpm. Each cylinder has a volume of 50 inches squared? Ans✓✓-
113 cfm
19.06.) If a reciprocating compressor's unloaders fail in the open position which of
the following will take place? Ans✓✓-Evaporator pressure will rise
19.07.) Clearance pockets are equipped with a small manual valve that makes it
possible to open and close the pocket. What effect does it have on the system
when it has been adjusted to the open position? Ans✓✓-The compressor moves
less vapor
19.08.) Freon compressors are sometimes equipped with magnetic cylinder
bypass valves. One of the functions of these valves is to? Ans✓✓-Starting the
compressor
19.09.) In a Freon compression system, which of the following would be
associated with a reduction in capacity? Ans✓✓-? ask professor
