Topics: All categories in the pool
1: Starting relays for a single phase compressors are used to remove the starting circuit from operation when the motor reaches approximately ____ percent of its speed.
- 50
- 100
- 24
- 75
2: Refrigerant restricted in 2004 but used for transition for decades:
- R-123
- R-22
- R-11
- R-134A
3: What type refrigerant is NOT ozone depleting?
- HCFC
- Halon
- HFC
- CFC
4: What is a Category "M" fluid?
- A fluid which is nonflammable, nontoxic, not damaging to human tissues, does not exceed 150 psig, and the designed temperature is between -20F to 366F
- Any fluid that exceeds 150 psig and has design temperatures over 366F
- A toxic fluid, which can produce serious irreversible harm to persons on breathing or bodily content
- A typical refrigerant used on newer air conditioning and heat pump systems
5: What would be the classification for Stop & Shop grocery store?
- Industrial
- Large mercantile
- Instituional
- Place of assembly
6: Two systems using separate refrigerants that are superimposed upon one another is called
- indirect
- cascade
- single stage
- booster
7: Total heat of a substance is considered
- empathetical
- specific heat
- sensible heat
- enthalpy
8: How many volts would you read on a 480V system phase to phase?
- 480
- 1/3 the voltage
- 277
9: What type of voltage causes the winding in a potential relay to open?
- BEMF (Back Electro-Motive Force)
- 24V control voltage from the thermostat
- 120V line voltage
- None of the above
10: How many gallons of water do you need per pound of ammonia?
- 1
- 100
- 50
- 10
11: R-410A is classified as a ____ refrigerant on the safety matrix.
- A-2
- B-1
- A-1
- B-2
12: A low oil switch is typically
- non used on semi-hermetic compressors over 10 ton capacity
- manual reset
- time-delay auto reset
- automatic reset
13: The Department that certifies the transportation of refrigerant is the
- EPO
- DOT
- EPA
- RSES
14: What is absolute humidity?
- the amount of moisture in the air per one pound of 50% RH air
- the amount of moisture in the air in grains of cubic feet of volume
- the amount of moisture in the air in grains of square feet of volume
- none of the above
15: With a 5/8" X 5/8" x 3/4" tee, what size is the center connection?
- 1/2"
- 3/8"
- 3/4"
- 5/8"
16: What section governs pressure vessels?
- Section 8 ASHREA 15 ASME unfired
- Section 1 ASHREA 15 ASME fired
- OSHA
- Section ASHREA 34
17: What is the purpose of a surge capacitor on a contactor?
- to keep the contactor pulled in
- to provide smoother start/stops
- to balance the sine waves
- to protect low voltage equipment
18: Which occupancy can ammonia be used in?
- industrial
- commercial
- redifential
- depends on the quantity of freon
19: The total amount of refrigerant stored in a machinery room in all containers not provided with relief valves shall not exceed
- 550 lbs
- 660 lbs
- 55 lbs
- 330 lbs.
20: A chilled water pump's suction gauge reads 10 psig. The discharge gauge reads 48 psig. What is the head in feet the pump is working against?
- 58
- 96
- 88
- 38
21: Sensible heat is the heat added to a substance to
- raise its temperature
- freeze it
- cause evaporation
- change its state
22: Megaohm meter's main function is
- to detect weak motor winding insulation of a refrigeration or air conditioning compressor by creating high DC voltages to the compressor
- to detect very high resistances to ground of refrigeration or air conditioning compressors
- to test very high value capacitors for large 3-phase refrigeration compressors and blower motors.
- Both a and b are correct
23: What is not a requirement of a Class T machine room?
- Tight fitting doors
- Automatic ventilation
- Fire hose connected to the building fire protection system.
- Self-closing doors
24: The critical temperature of a refrigerant gas occurs when
- any decrease in pressure will cause condensation
- any increase in pressure will not liquefy the gas
- the gas is no longer saturated
- the gas returns to a liquid
25: A single pole-double throw switch used how many wires excluding the ground wire?
- three
- two
- five
- four