Tpc 436 Flashcards
In a cooling system one of the main lines in the piping system is the _______ line.
Liquid
Steel pipe is typically joined by means of?
Flanges
Tubing is often preferred over piping in a cooling system because it?
Absorbs vibration better
Refrigeration tubing is typically joined by?
Soldering
When brazing tubing to a fitting, you should first heat the ________ until the ______ melts.
Tubing
Flux
The function of the discharge line in a refrigeration system is to?
Convey the refrigerant to the condenser
The entrainment of compressor oil is the _________________________ with the moving refrigerant.
Drawing in and transporting of oil
In order to keep entrained oil droplets moving through the piping, the refrigerant must move at __________ in horizontal piping and __________ in a vertical riser
500 to 700 fpm
750 to 1500 fpm
Refrigerant can be prevented from collecting in the compressor during the off cycle by installing a _________ in the __________.
Check valve
Discharge line
Accessories often added to a discharge line include a ___________.
Discharge muffler
Subcooling is desirable in the liquid line because it?
Reduces the volatility of the refrigerant
If the pressure in the liquid line drops, flash gas can form, which can reduce the?
Refrigerant effect
With halocarbons refrigerants, the movement of oil is better in the liquid line than in the discharge line, because the…
Oil is miscible in most liquid refrigerant
A liquid receiver is used to?
Store all the refrigerants during repairs
The purpose of a solenoid valve in the liquid line is to stop the flow of refrigerant to the?
Evaporator
A double suction riser installed in a cooling system enables the system to operate at maximum load without creating excessive _________ in the suction line.
Pressure drop
An accumulator in the suction line traps oil and liquid refrigerant to keep it from entering the __________. A heater in the accumulator evaporates the __________.
Compressor
Refrigerant
An evaporator-pressure regulator valve closes part way if the pressure at the evaporator outlet becomes to ____. A crankcase-pressure regulator valve closes part way if pressure at the compressor inlet becomes to _____.
Low
High
The suction line is insulated in order to prevent or reduce ________________ of the line.
Condensation on the outside
The amount of oil that can build up in the suction line of an idle single-compressor system is much _______ than the amount that can build up in an idle compressor of a multiple-compressor system. To prevent damage from excessive build up, the suction line should include a trap with the minimum rise of ______.
Less
14 inches
Piping problems that result in operating problems are often caused by?
Liquid hammer
Which of the following expansion joints can be used in a refrigerant line?
Bellows
Which kind of support is appropriate for a horizontal piping run of 15ft long?
Rod type hanger
The problems caused by vibration in the piping of a cooling system include?
Damage to the valves and controls
Insulation is needed on the liquid line if the line is ________ than its surroundings. The purpose of insulation on the liquid line is to prevent the loss of any _________ of the refrigerant.
Much colder
Subcooling
