Isolating the break in a circuit by starting at a point where there is correct voltage, and moving one lead from point to point towards the non-functional load is called:
A) Hop scotching. B) Quantitative analysis.
C) Running the rat. D) Shot gunning.
Q. 2A technician notes that an operating air conditioning system has ice formed on the suction line at the condensing unit. The technician can reasonably assume that:
A) The evaporator coil is also frozen over. B) The refrigerant charge is high.
C) The condenser coil is also frozen over. D) The refrigerant charge is low.
Q. 3Before opening the compressor crankcase to take an oil sample, you should:
A) Increase the crankcase pressure with nitrogen to at least 100 psig.
B) Get the sample tube ready because the oil comes out very quickly under pressure.
C) Valve off the compressor and recover the refrigerant down to 1 - 2 psig.
D) Position yourself directly in front of the drain port.
Q. 4The largest capacity chillers use
A) Centrifugal compressors B) Rotary compressors
C) Reciprocating compressors D) Scroll compressors
Q. 5Technicians should be cautious when taking an oil sample from a semi-hermetic compressor because:
A) The oil is highly flammable.
B) The oil is highly toxic.
C) The oil sample must be done with the compressor running.
D) The compressor crankcase is under pressure.
Q. 6What happens when the electrical contacts close in the motorized valve?
A) the circulator pump starts B) the circulator pump stops
C) the bypass pump stops D) the bypass pump starts