Topics: All categories in the pool
1: Where a refrigeration or air conditioning system is installed,
- the form or certificate shall be authorized by the Department of Public Safety
- A field inspection shall be made before it is put into service
- it shall not be operated below prescribed pressuers
- The company who installed the system must notify the fire department in the jurisdiction where installed
2: A micron is
- one millonths of a centimeter
- one thousandths of a millimeter
- a larger unit of measurement than Hg
- one millonths of a micrometer
3: A single pole-double throw switch used how many wires excluding the ground wire?
- three
- five
- two
- four
4: When is the only time you can leave a service container attached to a system?
- Leaking system
- Recovery
- Charging
- Both b and c
5: Ammonia vaporization takes place at what temperature?
- -110F
- -460F
- -32F
- -28F
6: The main purpose of the accumulator is to
- prevent liquid slugs at the compressor
- store liquid refrigerant
- provide space for the accumulation of oil and containminants
- provide space for vapor to accumulate
7: What is used to check very low air pressures in air conditioning duct?
- Barometer
- Vacuum gauge
- Manometer
- Anemomter
8: A declaration test is needed when the system contains more than
- 120 lbs
- 55 lbs
- 110 lbs
- 65 lbs
9: R-410A can segregate in the system or chemically change its composition due to a leak.
- True
- False
10: Low pressure systems have what kind of compressor?
- Reciprocating
- Rotary
- Scroll
- Centrifugal
11: How do you find net oil pressure on a compressor?
- discharge pressure - suction pressure
- gross oil pressure - suction pressure
- gross oil pressure - discharge pressure
- all of the above
12: R-22 is considered a(n)
- HFC
- HCFC
- HCFCH
- CFC
13: Lithium-bromide, Li-Br, is best characterized as a
- salt
- sugar
- sand
- soil
14: A motor starter contains a thermal overload and a
- contactor
- solenoid
- transformer
- 3-way relay
15: High pressure controls should be set no higher than
- 10% of set point
- 90% of set point
- 25% of set point
- 80% of set point
16: 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
17: Which refrigerant(s) is an HFC?
- R-22
- R-410A
- R-502
- All of the above
18: How much clearance do you need around the perimeter of electrical panels?
- 12"
- 18"
- 36"
- 24"
19: What is potential measured in?
- Volts
- Henrys
- Amps
- Ohms
20: Ammonia (NH3) is a group III refrigerant
- True
- False
21: Where would the EPR valve be located on a multiple evaporator system?
- outlet of low temperature evaporator
- inlet of the low temperature evaporator.
- outlet of high temperature evaporator
- outlet of the liquid line
22: 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
23: Sublimation occurs when
- gas is formed directly from a solid
- gas is formed from a liquid
- ice melts and turns to water
- liquid is formed from a gas
24: The density of a gas refers to
- pounds per absolute pressure
- pounds per square foot
- cubic feet per pound
- pounds per cubic foot
25: An air conditioning system rated for 36,000 BTU's is equivalent to
- two tons of cooling
- 12,000 tons of cooling
- three tons of cooling
- one ton of cooling