RETA CARO QUESTIONS AND ANSWERS ALREADY PASSED

RETA CARO QUESTIONS AND ANSWERS ALREADY PASSED Which refrigerant has the highest mass flow requirement at the same evaporator and condensing temperature? CFC-12 which refrigerant is the first to be phased out by Montreal Protocol CFC-12 As the ratio between the evaporator and condensing pressure increases the theoretical discharge temperature increases Under the Montreal Protocol as long as a technician does not perform work on the refrigerant containing portions of a system they do not need to be certified Refrigerant leaks are detected using Either a sulfur stick on ammonia or electronic leak detector for CFCs or HCFCs the primary reason for concern about CFC-12 concentration in an engine room is oxygen deprivation the published lower explosive limit for ammonia is 16% under normal conditions an ammonia vessel should only be filled to what percentage 80% which refrigerant can be detected by its odor even in low concentrations R-717 Which refrigerant would have the lowest condensing pressure at 95 Degrees F CFC-11 A cartridge type gas mask may legally be used for personal protection when the type of the hazard is known and the concentration is known a vapor can NOT be subcooled what kind of measure is a to of refrigeration a rate of heat transfer in BTUs per Unit of time which two forms of heat transfer is most common in refrigeration conduction and convecton the condition of a boiling liquid is what saturated What kind of measurement is a ton of refrigeration A rate of heat transfer in BTUs per unit of time Which is greater 10psia or 10psig 10psig is greater than 10paia The latent heat of condensation of a substance is the same as what The latent heat of evaporation of the substance Superheat is found in an air conditioning system in the: Compressor suction line and it's discharge line Subcooled refrigerant can only be what Liquid Superheated refrigerant can only be ? Vapor Saturated refrigerant can be what? A liquid, vapor or a combination of the two What do you multiply the mass flow rate (lbs./min) by to determine the vapor flow rate through the compressor Specific volume (cubic ft./lbs) Three factors to consider when choosing a refrigerant are Cost, available, and safety One positive characteristic of halocarbon refrigerant is They are usually not flammable Which refrigerant requires the largest compressor displacement per ton R-134a What is not a direct symptom of air in an ammonia system