Classrep2

The Fahrenheit scale is based on boiling water at sea level at what temperature? A: 459 degrees B: 212 degrees C: 180 degrees D: 100 degrees - ANSWERB: 212 degrees Zero pounds gauge corresponds on the absolute scale to: A: 144 B: 212 C: 14.7 D: zero - ANSWERC: 14.7 Hidden heat in refrigeration work is referred to as: A: Intensity of heat B: Latent heat C: Heat a thermometer can "sense" D: Cold - ANSWERB: Latent heat Absol...

What are the symptoms of a TXV air conditioning system if it has lost its charge: - ANSWERThe superheat will increase and the low-side pressure will decrease A customer who owns a split air conditioning system complains that his system has been running but his house doesn't seem to be cooling properly. When the service technician arrives on the job, he or she finds that the indoor blower is operating and the air filter is clean. The condenser fan on the outdoor unit is operating, but he or...

During an annual service check up, it is discovered that there is a moderate amount of resistance on a "bellyband" crankcase heater. What does this condition indicate? A. the crankcase heater will operate B. the crankcase heater will not operate C. the crankcase heater is open D. the crankcase heater voltage must be increased for proper operation - ANSWERA. the crankcase heater will operate High superheat is a symptom of: A. a system overcharge B. a clogged air filter C. a bl...

A technician has determined a supply in a flexible duct system is leaking. What should be checked? - ANSWERAll connections inner and outer layers. Electronic air cleaners can operate with internal voltages as high as? - ANSWER5000v Why do some electromechanical type thermostats require connections to both the hot side and common side of the low voltage transfromer - ANSWERDisplay lights must be powered using both sides of the line the continuity reading on a functional fuse will be - AN...

Ch. 1-1 The ability to utilize all types of communication skills is ________ to the HVACR technician. a) not as important as "hands-on" technical skills b) somewhat important c) unimportant d) very important - ANSWERd) very important Ch. 1-2 It is important to be _______ in filling out service orders so that office staff, other technicians, and customers will know what work you completed on the job. a) clear b) complete c) concise d) all of the above - ANSWERd) all of the abov...

A suction line accumulator should be used in a residential heating pump only when recommended by the manufacturer if: a. Long refrigerant lines increase system charge over recommended maximum charge b. added oil dilution is required to maintain proper lubrication c. the system has low vapor line pressure drop and accumulator is added to improve efficiency d. the system does not include a high pressure switch or time delay - ANSWERA. Long refrigerant lines increase system charge ove...

The part of an air conditioning system that changes the refrigerant from a low-pressure gas to a high-pressure gas is the: - ANSWERcompressor The part of an air conditioning system that changes the refrigerant from a high-pressure gas to a high-pressure liquid is the: - ANSWERcondenser The part of an air conditioning system that changes the refrigerant from a low-pressure liquid to a low-pressure gas is the: - ANSWERevaporator A split-system air conditioning unit has: - ANSWERthe compre...

A system is supplied from the factory with a charge of 5 pounds 10 ounces for a 15 foot line set. The line set is 25 feet long. The manufacturer's instruction sheet specifies 0.6 ounces of refrigeration to be added for each added foot of refrigerant line set length. What is the total refrigerant charge for the system? A. 6 ounces B. 5 pounds C. 5 pounds 10 ounces D. 6 pounds - ANSWERD. 6 pounds 25ft - 15ft = 10ft 10ft x .6 = 6 ounces 5 pounds + 10 ounces + 6 ounces 5 pounds + 16...

Low airflow over a residential split system air conditioning evaporator can cause A: Liquid flood-back to the compressor B: A decrease in compression ratio C: An increase in suction line superheat D: Oil logging in the evaporator - ANSWERA: Liquid flood-back to the compressor Which of the following is the correct sequence of work? A: Attach gauge manifold, recover refrigerant, replace filter core, evacuate the system, recharge the system. B: Recover refrigerant, ev...

A good evacuation of a refrigerant circuit to remove non-condensables will help insure: A.) higher condensing temperatures B.) higher suction pressures C.) low suction line pressure drop D.) higher efficiency and capacity - ANSWERD.) higher efficiency and capacity A condensing unit should be mounted on a slab that is level to: A.) allow an accumulated water to evenly run out of the cabinet B.) increase airflow through the fin area C.) prevent the unit from tipping over D.) make certai...