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Questions And Answers
Sensible Heat - correct answer ✅Causes a change of temperature in a substance. Latent heat - correct answer ✅Heat added to a substance without a rise in temperature. Superheat - correct answer ✅Heat added to the refrigerant in the vapor state after the evaporator process. How does a scroll compressor work? - correct answer ✅By means of Involute spirals Convection - correct answer ✅The movement of heat by fluid or air Conduction - correct answer ✅Movement of heat by direct contact
Questions And Answers
BTU Definition - correct answer ✅Standard unit for measuring heat in a substance. British thermal unit. Amount of heat required to raise 1lb of water 1° When does refrigerant give up heat? - correct answer ✅When it condenses Refrigerant in the suction line may be what? - correct answer ✅Slightly warmer than the saturation temperature to prevent liquid slugging of the compressor. The state of refrigerant in the suction line? - correct answer ✅Low pressure, low temperature vapor. The state of the refrigerant entering the condenser? - correct answer ✅High pressure, high superheated vapor. What does the evaporator do? - correct answer ✅Transfers heat from the refrigerated space into the refrigerant.
Questions And Answers
What does a compound pressure gauge measure? - correct answer ✅Pressure and Vacuum Liquid Slugging is? - correct answer ✅Liquid refrigerant in the compressor clearance space. What has an effect on reciprocating compressor capacity? - correct answer ✅Clearance Space. Most efficient Compressor? - correct answer ✅Scroll compressor Condenser order of functions? - correct answer ✅De-superheats, Condenses and Subcools What is Subcooling? - correct answer ✅Cooling of a liquid below its condensing temperature.
Questions And Answers
Three types of Condensers? - correct answer ✅Air cooled, water cooled and evaporative cooled As water flows through the water cooled condenser, how many degrees is the water raised? - correct answer ✅7-10 Degrees The heat removed from the refrigerant by the condenser is? - correct answer ✅Both sensible and latent heat. What is an energy recovery ventilator used for? - correct answer ✅To recover warm air from the condenser to the conditioned building. When testing the efficiency of an air-cooled condenser the condensing temperature could be? - correct answer ✅30 to 20 degrees higher When testing the efficiency of a water-cooled condenser the condensing temperature should be? -
Questions And Answers
A decrees in superheat on a TXV system causes? - correct answer ✅The TXV too close. In the evaporator latent heat is transferred from? - correct answer ✅Refrigerated space to refrigerant. Where should liquid line drier be placed? - correct answer ✅Between the condenser and metering device. A temperature differential across a filter- drier indicates what? - correct answer ✅A restricted filter-drier. Where is the sight glass located? - correct answer ✅In the liquid line before the metering device. Bubbles in the sightless would be an indication of what? - correct answer ✅A refrigerant blend with high temperature glide.
Questions And Answers
What would a High discharge line pressure and low liquid line pressure indicate? - correct answer ✅An oil logged condenser. In a pump down system the solenoid is located where?
correct answer ✅Before the metering device. A liquid to suction heat exchanger is used for what - correct answer ✅To increase liquid sub-cooling. The oil pressure safety switch is operated by? - correct answer ✅The difference between crankcase pressure and oil pressure. A low pressure oil cutoff switch is used for what? - correct answer ✅To prevent low pressure oil in the crankcase. A partially frozen evaporator coil can be cause by what? - correct answer ✅A low charge.
Questions And Answers
Frost on the suction line indicates - correct answer ✅Its temperature is below the dew point 32 degrees On a fixed bore system a higher head pressure can cause what? - correct answer ✅More refrigerant to flow through the metering device.
