Topics: All categories in the pool
1: A positive displacement compressor is
- a compressor in which the increase in pressure is attained by changing the internal volume of the compression chamber
- where the compressor's suction pressure and the compressor;s discharge pressure is more than 50 PSI
- a compressor in which the increase in pressure is attained by changing the internal pressure of the compression chamber
- is a reciprocating type compressor with 2 or more pistons
2: Joints in piping for refrigeration containing parts must withstand temperatures of ___?
- 1000F
- 600F
- 800F
- 700F
3: All machine rooms must be outfitted with a detector that _______?
- activates an audible alarm
- activates a visual alarm
- starts the ventilation system
- All of the above
4: A rule of thumb in air conditioning is ____ CFM per ton?
- 600
- 100
- 400
- 500
5: A EPR valve is installed on what type of evaporators?
- plate evaporators
- shell and tube evaporators
- high-temperature evaporators
- low-temperature evaporators
6: According to ASHRAE Standard-15 9.8 Positive Displacement Compressor Protection, the pressure-relief device discharge into
- the low-pressure side of the system
- the high side of the system
- the liquid receiver
- both a and c are correct
7: What should not (and can not) be located between a pressure imposing device and a pressure-limiting device?
- Stop valve
- Foot valve
- Muffler
- Moisture indicator
8: A R-410A system running with a condensing temperature of 110F and 50F evaporator temperature will read pressures of ___ on the high side and ___ on the low side
- 226 psig, 68 psig
- 455 psig, 185 psig.
- 257 psig, 77 psig
- 365 psig, 120 psig
9: R-22 falls under which safety classification?
- B-1
- A-2
- A-1
- B-2
10: The purpose of a receiver is
- a vessel to store refrigerant outside the system
- to increase the capacity that the system can hold
- to use a a later date
- all of the above
11: The gauge thickness required on a CO2 tank construction is
- 1/16"
- 1/8"
- 3/32"
- 5/16"
12: If your suction line is warmer than the room temperature, this may indicate
- a low charge
- below normal superheat
- an over charge
- plugged air filter
13: Class A refrigerants are considered
- toxic
- flammable
- non-toxic
- non-flammable
14: 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.
- 350
- 50
- 100
- 550
15: The rupture disc on a low-pressure chiller typically releases pressure at
- 15 psig
- 0 psig
- 10 psig
- 5 psig
16: The best way to determine the voltage requirement for an electrical component is to
- read the voltage with a mulitmeter
- read the nameplate data
- check with the utility company
- determine the capacity of the service panel
17: Heat is a form of
- energy
- power
- matter
- work
18: Name an HCFC refrigerant(s):
- R-22
- R-123
- R-11
- both a & b
19: A 50 VA control transformer with a 25 volt control output would be rated for _________ amps.
- 1250
- 2
- 2.5
- There isn't enough information to answer.
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?
- 88
- 58
- 96
- 38
21: When is the space above a drop ceiling calculated as space for refrigerant limit quantities?
- When there are sprinklers above
- When its white
- When it's used as part of a supply or return air system
- When there is a space 6' or more above it
22: A thermometer inside a duct measures ____ heat.
- specific
- hidden
- sensible
- latent
23: A factory-sealed system containing less than 22lbs. of Group A1 refrigerant
- shall have a pressure limiting device installed on the high side of the system
- shall be inspected by the Boiler of Inspectors bi-annually
- does not require a pressure-limiting device
- shall have a pressure limiting device and a pressure relief valve installed
24: A person holding a license as a refrigeration technician may connect or disconnect for the purpose of installation, repair, or replacement, any electrical device or control to be a part of a refrigeration or air conditioning system, from the
- breaker panel in
- 24 volt secondary side of the Class 2 transformer to the thermostat
- first disconnect in
- load-side of the contactor in
25: A solder joint melts at temperatures of
- 1,200F to 1,500F
- 400F to 800F
- less than 400F
- 600F to 900F