Chapter 10 Flashcards
Who sets refrigerant cylinder regulations?
The department of transportation also known as the DOT
Large for refrigerant cylinders are protected against bursting buy
A protective cap
What type of cylinders are often positioned upside down with the valves at the bottom
A storage cylinder
The operating element used in the pressure gauges that is made of a thin walled tube of metal Bent into circular shape is called a
Bourbon tube
A an extra spring in a pressure gauge used to adjust the gauges calibration is called a what?
Retarder
A pressure gauge that is specifically designed to measure lower than atmospheric pressure is called a
Vacuum gauge
A pressure gauge designed to measure pressure above and below atmospheric pressure is a
Compound gauge
A pressure gauge that can read high pressure values on a single continuous scale from 0 to 180 psi is a
High pressure gauge
A service port is closed off from the refrigeration system when the service valve is in what position?
Back seated
Which of the following service valves is located on the low side of a refrigeration system
Suction line service valve
During normal system operation hot high pressure refrigerant vapor flows through Which valve?
Discharge service valve
This is used mostly for checking pressure and does not have a service valve to control the flow of refrigerant what is it
Access port
In externally threaded valve with a spring loaded center pin is called a
Schrader valve
The technician must use this to access small hermetic systems that do not have service valves or access ports
A piercing valve
The process of removing unwanted air vapor dirt and moisture from gauge manifold hoses by venting them to the atmosphere is called what?
Purging
Which system procedure is normally done with both hand valves opened On a gauge manifold connected to a refrigeration system
Evacuation
Name the three areas where leaks are likely to occur?
Tubing connections
Braised joints
High vibration areas
The leak detection method involving the application of a soap and water solution to areas will leaks are suspected is the
Bubble solution
The leak detection method that uses ultraviolet light to find leaking refrigerant is the
Fluorescent
The leak detection method that involves burning a fuel gas near a copper plate and using a rubber hose to siphon air from areas suspected of leaking refrigerant is
Halide torch leak detectors
Which of the following is a disadvantage of using an electronic leak detector
It produces false alarms near urethane insulation
The leak detection method that the text the sound of vapor escaping from a system is
Ultrasonic detector
A device used for creating vacuums to dehydrate an HVAC system is
Vacuum pump
Which of the following terms used to specify the speed at which gas can be pumped through a vacuum pump
Free air displacement
What acts as a fluid seal between air , gases and contaminates entering a vacuum pump from the refrigeration system
Vacuum pump oil
Cleaning a refrigerant for reuse by oil separation in single or multiple passes through a filter dryer defines
Recycling
Removing a refrigerant from system in storing it in an external container regardless of the condition of the refrigerant is
Recovery
Re-processing a refrigerant so that it is chemically pure is
Reclaiming
An instrument used to monitor the weight of refrigerant cylinder as refrigerant is being charged into or recovered from the system is called
Solenoid valve built into a scale