Topics: All categories in the pool
1: The rupture disc on a low-pressure chiller typically releases pressure at
- 15 psig
- 0 psig
- 10 psig
- 5 psig
2: Excessive head pressure is often caused by
- thermostat set too high
- insufficient refrigerant
- leaking reed valve on the discharge side
- air cooled condenser is plugged
3: Pressure relief devices are marked with a ____________ signifying compliance with the ASME Boiler & Pressure Vessel Code.
- UL and UM
- UM or UL
- UV or UR
- UL and UR
4: What is the refrigerant dichlorodifluoromethane?
- R-12
- R-134A
- R-123
- R-22
5: A secondary coolant is defined as
- a combination of interconnected parts from a closed circuit in where fluid is circulated for the purpose of cooling for a refrigeration system.
- any refrigerant direcly in contact with the cooling space for process cooling
- a low temperature refrigerant used for cascading systems
- any liquid used for the transmission of heat without a change of state in A/C refrigeration systems having flash point above 150F
6: The best way to detect ammonia in brine is
- potassium of line
- nessler regaent
- carbonation of soda
- CO2 gas
7: R22 and 410A operate at the same range of condensing and evaporating temperatures
- true
- false
8: System design pressures must take into consideration, not only, pressures found during normal operation but also what?
- When it's cold out
- When there is a malfunction on the high side
- When its warm out
- All of the above
9: Watt's Law indicates Volts X Amps = _________.
- Current
- Watts
- Ohms
- Resistance
10: Dual-pressure relief devices should be installed on
- vessels of 10 cubic feet or less
- vessels of 3 cubic feet or less
- vessels of 3 cubic feet or more
- vessels of 10 cubic feet or more
11: An air conditioning system rated for 36,000 BTU's is equivalent to
- 12,000 tons of cooling
- three tons of cooling
- two tons of cooling
- one ton of cooling
12: How would you know if there was a loss of crankcase pressure?
- oil level will rise
- oil will foam
- oil will thicken
- oil will thin out
13: How many square inches per square foot?
- 64
- 144
- 24
- 98
14: When a receiver is greater than 3 cubic feet but less than 10 cubic feed, what is the minimum relief device required?
- fusible plug
- relief valve
- rupture disc
- all of the above
15: The External equalizer of a TXV compensates for
- pressure within the system
- pressure within the evaporator
- pressure drop across the condenser coil
- pressure drop across the evaporator coil
16: When air is ducted through a machine room that services occupied space, What must be done?
- Ducted and sealed
- Flanged and gasketed
- Welded and seamed.
- Insulated and cross broke
17: Refrigerant piping crossing an open space that affords passageway in any building shall not be less than _____ feet above the floor unless piping is located against the ceiling.
- 7.25'
- 8'4"
- 7.00'
- 9.00'
18: What is used to check very low air pressures in air conditioning duct?
- Manometer
- Barometer
- Vacuum gauge
- Anemomter
19: When the compressor is below the condensor
- traps are needed on the oil return line
- traps are needed on the discharge line
- traps are not needed on this type of system
- traps are needed on the suction line
20: A direct system
- is a self-contained complete factory made and tested system
- is one which encloses a separate body of evaporative refrigerant
- is on where brine is cooled & circulated to the space refrigerated
- is where the refrigerant comes in contact with the space refrigerated
21: R-717 is
- water
- trichloromethane
- carbon dioxide
- ammonia
22: E = I X R is
- Watts Law
- Amps Law
- Impedance Law
- Ohms Law
23: The 522 CMR 9.00 has adopted for reference ASHRAE ____
- III
- 15
- 10
- 25
24: A compressor that increases vapor pressure by changing the internal volume of the compression chamber is called?
- Positive displacement
- Pressure induced displacement.
- Non-positive displacement
- Low Pressure displacement
25: Institutional occupancy is
- a premise or that portion of a premise where large numbers of people congregate and from which occupants cannot quickly vacate the space.
- a premise or that portion of a premise from which, because they are disabled, debilitated, or confined, occupants cannot readily leave without the assistance of others.
- a premise or that portion of a premise where people transact business, receive personal service, or purchase food and other goods.
- None of the above