HVAC-R Assessment (OLD- DO NOT USE))

What is the definition of subcooling?  

• Temperature of vapor above boiling temperature of its liquid at that pressure.  

• Heat characterized by a change of state of the substance. 

• The temperature at which moisture begins to condense out of the air. 

• Cooling of liquid refrigerant below its condensing temperature.     

• I'm not sure

Define Superheat:

• Temperature of vapor above boiling temperature of its liquid at that pressure.

• Heat characterized by a change of state of the substance.

• The temperature at which moisture begins to condense out of the air.

• Cooling of liquid refrigerant below its condensing temperature.

• I'm not sure

Which of the following components is not used in the secondary side of a glycol system?

• Balance valve

• Pump

• Expansion tank

• Condenser

• I'm not sure

A liquid line filter drier is installed in the low side of the system.

• True

• False

• I'm not sure

A valuable tool that service technicians use to quickly look up the pressure and corresponding temperature of refrigerant.

• Psychrometric Chart

• Enthalpy Chart

• Pressure Temperature Chart

• Power Factor Chart

• I'm not sure

Define Saturated Suction Temperature (SST):

• Temperature at which the refrigerant changes from a vapor state to a liquid

• Temperature at which the refrigerant changes from a liquid state to a vapor

• Temperature at which the refrigerant changes from a liquid state to a solid

• Temperature at which the refrigerant changes from a solid state to a vapor

• I'm not sure

What component in a refrigeration system do you adjust to set the superheat?

• Compressor

• Condenser

• Evaporator

• Thermostatic Expansion Valve

• I'm not sure

Where do you measure superheat?

• After the compressor

• Before the TXV

• Leaving the evaporator

• Leaving the condenser

• I'm not sure

Where do you measure subcooling?

• After the compressor

• Before the TXV

• Leaving the evaporator

• Leaving the condenser

• I'm not sure

Using this pressure temperature chart, calculate the superheat for this evaporator. Suction line temperature is 12﮿ F and suction pressure is 26 PSIG.

• 4° superheat

• 4° subcooling

• 8° superheat

• 8° subcooling

• I'm not sure