Topics: All categories in the pool
1: The 522 CMR 9.00 has adopted for reference ASHRAE ____
- 25
- 15
- 10
- III
2: A normally operating R-410A system with a condensing temperature of 110F will have a high side pressure of around ______ psig
- 327 psig
- 365 psig
- 255 psig
- 125 psig
3: Group A2 refrigerants have a ______ toxicity rating than Group B1 refrigerants.
- lower
- the same
- there is no Group B1 refrigerants
- higher
4: High pressure controls should be set no higher than
- 10% of set point
- 25% of set point
- 80% of set point
- 90% of set point
5: The outer portion of shell of the compressor used on low-pressure chillers is called the
- volute
- nozzle
- suction
- baffle
6: At higher altitudes, the boiling point of refrigerant is
- equal to the coefficient of water at 32F
- the same
- lower
- higher
7: 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
8: Name an HCFC refrigerant(s):
- R-22
- R-123
- R-11
- both a & b
9: The measurement of heat in a particular substance is
- sensible heat
- enthalpy
- latent heat
- specific heat
10: When must refrigeration system covered by the code be inspected?
- Upon installation
- Annually and when installed
- Annually
- Not required
11: A micron is
- one thousandths of a millimeter
- one millonths of a micrometer
- one millonths of a centimeter
- a larger unit of measurement than Hg
12: If the suction pressure is low and the evaporator temperature high, the cause will be a?
- overcharged
- starved evaporator
- too small evaporator
- compressor suction valve stuck open
13: Low ambient controls are used when
- economizers are used
- always
- on air conditioning systems only
- when systems run all year round
14: What device removes the start winding from the circuit of a split-phase motor once the motor reaches 75% of its rated load amps (RLA)?
- centrifugal switch
- printed circuit board (PCB)
- motor starter
- duel-voltage switch
15: Pi equals approximately
- 3.41
- 3.14
- 12,000
- 746
16: Volts x amps equals
- Watts
- Ohms Law
- Impedance
- Inductance
17: Which of the following is an inorganic refrigerant?
- R-22
- Ammonia
- Chlorofluorocarbons
- All of the above
18: 14.7 psia is equivalent to
- atmospheric pressure at seal level
- 29.92" Hg
- 0 psig
- All of the above.
19: R-410A is classified as a ____ refrigerant on the safety matrix.
- A-1
- B-2
- B-1
- A-2
20: All welding done on any refrigeration system or piping covered by 522 CMR 9.00 shall be performed by a according to Section IX of the ASME code
- licensed welder
- welder qualified
- competent welder
- licensed technician
21: 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?
- 38
- 96
- 88
- 58
22: When a refrigeration or air conditioning system is installed
- a field inspection shall be made before it is put into service
- it shall be approved by the owner for proper operation.
- the form of certificate shall be authorized by the Department of Pubic safety
- it shall not be operated below prescribed pressures
23: When using nitrogen for brazing, the pressure should be:
- 125 psig
- Very low
- 50-100 psig
- Slightly below atmospheric
24: When this is installed on the high side of a system, it must be capable of reading 1.2 times the design pressure (ASHRAE 15 9.11.3)
- Pressure gauge
- Temperature gauge
- Sight glass gauge
- All of the above
25: What is potential measured in?
- Amps
- Volts
- Henrys
- Ohms