(Exam Code A-02)
_________ can be used for leak detection and is safe with all refrigerants. - ANS-soap/ bubble
answer
10 lbs. Of refrigerant pass thru a water cooled condenser and gives up 20 Btu's of warmth in
keeping with lbs. At the equal time, 10 lbs. Of water passes through with an entering
temperature of 80 F. The temperature of the water leaving the condenser is; - ANS-100 F
A clean glass could indicate; - ANS-all liquid refrigerant.
A compound stress guage measures; - ANS-pressure and vacuum.
A compressor that has broken valve with motive those signs; - ANS-excessive suction stress
and coffee discharge strain
A condenser that is utilized in a low ambient temperature conditions should have a method of
preserving a workable head pressure. This can be executed by;
a) fan biking
b) air shutters or dampers
c) condenser flooding
d) any of the above - ANS-d) all of the above
A customer calls on the first warm day in the spring and complains of no cooling. Upon
inspection, you fin that the sight glass indicates a full price, the liquid line is hot, and the unit is
cycling at the motor internal overloads. This will be caused by;
a) an overcharge of refrigerant
b) a grimy condenser
c) an inoperative condenser fan
d) any of the above - ANS-d) any of the above
A customer complains that their air conditioning gadget is jogging constantly, however no longer
cooling sufficient. The suction line is very bloodless and the compressor is sweating.
Technician "A" says this can be caused by low refrigerant price and needs to be leak examined
and repaired.
Technician "B" says that those signs ought to suggest restrained go back air waft or a grimy
evaporator.
, Who is accurate? - ANS-Technician "B" most effective.
A consumer reports that their residential break up machine had a compressor replaced closing
week via some other provider business enterprise. Now the unit isn't cooling nicely. When you
arrive and inspect the the unit, you find that the evaporator appears to be starved of refrigerant.
On analyzing the condensing unit, you locate that the liquid line is sweating where it leaves the
filter out-drier. This ifs a result of; - ANS-debris from the burned out compressor has clogged the
drier.
A lower in superheat reasons a thermostatic expansion valve to; - ANS-near.
A grimy evaporator in an air conditioning system will purpose these signs; - ANS-low suction
strain and low discharge pressure
A faulty condenser fan motor on an air conditioning machine will cause these signs and
symptoms; - ANS-excessive suction stress and high discharge strain
A hermetic device this is low on rate is indicated by means of; - ANS-low head strain
A liquid line filter out-drier have to be located; - ANS-between the condenser and the metering
tool.
A liquid receiver is used; - ANS-to keep liquid refrigerant.
A liquid-to-suction heat exchanger is often used to - ANS-growth sub-cooling
A low pressure cut off switch is to - ANS-establish a minimum operating pressure inside the
evaporator
A low refrigerant fee in an air conditioning device will cause these symptoms; - ANS-low suction
stress and occasional discharge stress
A low-aspect float metering tool is used - ANS-on a flooded evaporator
A mechanical shaft seal is vital on a; - ANS-open drive compressor.
A in part clogged capillary tube can reason; - ANS-a starved evaporator
A refrigerant overcharge in a capillary tube air conditioning gadget will purpose the signs; -
ANS-high suction strain and high discharge pressure
A refrigerat offers up warmness while; - ANS-it condenses.
A upward thrust in evaporator pressure causes the automated expansion valve to; - ANS-near