Topics: All categories in the pool
1: A machine room with a refrigerant system using ammonia shall
- be provided with a continuously operated ventilation system
- be considered a non-hazardous location in accordance with National Electrical code
- have no flame producing apparatus permanently installed and operated
- All of the above
2: Lithium-bromide, Li-Br, is best characterized as a
- sand
- salt
- soil
- sugar
3: When a refrigeration or air conditioning system is installed
- the form of certificate shall be authorized by the Department of Pubic safety
- it shall not be operated below prescribed pressures
- it shall be approved by the owner for proper operation.
- a field inspection shall be made before it is put into service
4: The leaving chilled water set point for comfort cooling is typically?
- 38
- 60
- 66
- 45
5: If the suction pressure is low and the evaporator temperature high, the cause will be a?
- overcharged
- compressor suction valve stuck open
- too small evaporator
- starved evaporator
6: A tachometer is an instrument used to measure
- speed
- static pressure
- air velocity
- RPM
7: Name a CFC refrigerant(s):
- R-11
- R-12
- R-123
- both a & b
8: Group A3 refrigerants have a ______ flammability rating than Group B1 refrigerants
- there is no Group B1 refrigerants
- the same
- higher
- lower
9: Foaming of oil in a compressor is most likely to occur
- when ambient temperature are low
- at start-up
- when there is insufficient air across the condenser(i.e., dirty coil)
- when the evaporator temperatures are below 32F
10: Pipe identification labels are required when the system contains more than
- 65 lbs
- 120 lbs
- 55 lbs
- 110 lbs
11: On a TXV, the purpose of an external equalizer is to?
- compensate for a pressure drop across the evaporator coil
- balance the evaporator load
- allow a greater adjustment spam
- Increase the pressure on the top of the power head diaphragm
12: What type of material can't be used on the outlet of a relief valve?
- Stainless steel
- PVC
- Magnesium alloy
- Copper
13: On a large centrifugal system, what meters the flow to the evaporator?
- Low side float
- Cap tube.
- High side float
- TXV
14: How many gallons of water per pound of ammonia do you need?
- 1
- 15
- 5
- 20
15: Ammonia systems use ____ pressure to adjust oil pressure
- discharge
- stream
- liquid
- air
16: When must refrigeration system covered by the code be inspected?
- Annually
- Not required
- Upon installation
- Annually and when installed
17: How much clearance do you need around the perimeter of electrical panels?
- 24"
- 12"
- 36"
- 18"
18: A total of all group A-2,B-2, A-3, and B-3 refrigerants shall not exceed ____ lb in the occupied areas and machinery rooms of institutional occupancies.
- 550
- 100
- 50
- 350
19: Pressure vessel having an inside diameter exceeding 6” with an internal pressure greater than 15psig shall be marked directly on or on the nameplate the letters _______________ signifying compliance with the ASME Boiler & Pressure Vessel Code.
- “UL”
- “UV”
- “U” or “UM”
- “UM” and “UV”
20: What is the purpose of a surge capacitor on a contactor?
- to balance the sine waves
- to provide smoother start/stops
- to keep the contactor pulled in
- to protect low voltage equipment
21: What effect does the temperature of air have on humidity?
- warmer air holds more moisture then cooler air
- cooler air holds more moisture then warmer air
- air has no effect of humidity
- none of the above
22: What measures gas pressure?
- Hygrometer
- Manometer
- Hydrometer
- Barometer
23: How would you know if there was a loss of crankcase pressure?
- oil will thin out
- oil level will rise
- oil will thicken
- oil will foam
24: What device measures the specific gravity of a substance?
- Thermometer
- Manometer
- Hydrometer
- Hygrometer
25: Where are the three places that the discharge from an ammonia relief valve be piped?
- To chemical neutralizing tank only
- Underground, into drain, into mechanical room
- Atmosphere, Tank containing water, where the AHJ indicates.
- None of the above.