更多"The expansion valve on a Freon syst"的相关试题:
[单项选择]The thermal expansion valve controls the amount of refrigerant that is allowed to flow to the （）.
A. compressor
B. cooling coils
C. condenser
D. receiver
[单项选择]A thermostatic expansion valve is properly controlling evaporator superheatAdjusting this valve to lower the superheat will result in a/an （）.
A. evaporator pressure decrease
B. evaporator coil over-feed
C. evaporator capacity increase
D. expansion valve diaphragm rupture
[单项选择]Thermostatic expansion valve are （）.
A. either all the way open or all the way closed
B. normally open
C. throttled depending on load
D. controlled by suction pressure
[单项选择]During working, thermostatic expansion valve should be （）.
A. either all the way open or all the way closed
B. normally fully open
C. throttled depending on load
D. controlled by liquefied pressure
[单项选择]The thermal expansion valve reacts directly to the （）
A. temperature in the space being cooled
B. liquid refrigerant pressure at the solenoid valve
C. pressure drop across the evaporator coils
D. refrigerant gas superheat at the coil outlet
[单项选择]After passing through the expansion valve the refrigerant should be in the state of （）.
A. vapor
B. liquid
C. solid
D. None of the above is tree
[单项选择]The bulb for the thermal expansion valve is located（）
A. in the middle of evaporator coils
B. near the evaporator coil outlet
C. near the evaporator coil inlet
D. on the bottom row of evaporator coils
[单项选择]The thermal expansion valve responds to the（）
A. amount of superheat in the vapor leaving the coil
B. amount of superheat in the liquid
C. temperature in the evaporator coils
D. pressure in the evaporator coils
[单项选择]When you adjust a thermostatic expansion valve, （）.
A. refrigerant must be bled off the sensing line before adjustments are made
B. all refrigerant must be pumped into the receiver before adjustments are made
C. time must be allowed for conditions to stabilize in the evaporator before further adjustments are made
D. all refrigerant must be routed through the dehydrator while changing the superheat setting
[单项选择]One function of the thermal expansion valve is to（）
A. act as a pilot from the solenoid valve
B. regulate the amount of refrigerant flow to the coil
C. regulate the water flow
D. turn the compressor off and on
[单项选择]If the thermal bulb of an expansion valve is incorrectly placed at the center of the coil instead of the end, it will （）.
A. increase the capacity of the coil
B. increase the superheat at the bulb
C. deliver more refrigerant to the coil
D. decrease the capacity of the coil
[单项选择]Because the expansion valve is just （） way open, the refrigerant is under low pressure in the evaporator.
A. little
B. few
C. a little
D. a few
[单项选择]In a centrifugal Freon refrigeration system, the overall capacity of the system is increased by（）
A. opening more bypass lines
B. opening additional expansion valves
C. adding refrigerant
D. speeding up the machine
[单项选择]The mechanical exhaust valve operation system is replaced by（）in an electronic controlled ME engine.
A. a system with a Hydraulic Power Supply (HPS) unit
B. a system with roller guides for exhaust valves
C. a system with an electronically controlled Alpha Lubricator
D. a system directly powered by electric motor
[单项选择]In the starting system, the automatic valve is controlled by（）, and the cylinder start valves are controlled by（）
A. pilot air；pilot air
B. handle；solenoid
C. handle；pilot air coming through the distributor
D. solenoid；pilot air coming through the distributor
[单项选择]Controls for a fixed carbon dioxide system shall be mounted（）.
A. directly outside the space protected by the system
B. as near the gas cylinders as possible
C. in the pilothouse
D. on the main deck near the bow
[单项选择]A branch line valve of a fire extinguishing system on a ship must be marked with the（）.
A. maximum pressure allowed at that branch
B. name of the space or spaces which it serves
C. date of the last maintenance inspection
D. pressure needed to maintain an effective stream at that point
[单项选择]A solenoid valve used in a refrigeration system should be installed （）.
A. with the axis of the solenoid horizontal, sensing temperature of the box, and upstream of the thermal expansion valve
B. upright, sensing temperature of the box, and upstream of the thermal expansion valve
C. upright, sensing temperature of the box, and downstream of the thermal expansion valve
D. upright, sensing heat of the tail coil, and upstream of the thermal expansion valve
