Topics: All categories in the pool
1: In an A/C unit, dirty filters will cause
- high discharge pressure
- high suction pressur
- low suction pressure
- low oil pressure
2: Usually dry bulb temperature is
- higher than wet bulb temperature
- same as wet bulb temperature
- not important and shall be ignored
- lower than dry bulb temperature
3: A device used to measure small pressure differences is the
- manometer
- anemometer
- pyrometer
- phsycometirc
4: R-12 is
- dichloromethane
- dichlorofluoromethane
- trichlorofluoromethane
- dichlorodifluoromethane
5: When air is ducted through a machine room that services occupied space, What must be done?
- Ducted and sealed
- Welded and seamed.
- Flanged and gasketed
- Insulated and cross broke
6: What does an anemometer measure?
- amperage
- temperature
- voltage
- velocity
7: A room having machinery but no flame producing apparatus permanently installed and operated is considered a
- Class A machinery room
- Class T machinery room
- Class B machinery room
- Class M machinery room
8: How is bring measured?
- hygrometer
- manometer
- hydrometer
- anemometer
9: The level of voltage caused by back electromagnetic force that opens the contacts of a potential relay in order to take the start capacitor out of the circuit is
- boost voltage
- lift voltage
- pick up voltage
- run voltage
10: Low ambient controls are used when
- when systems run all year round
- economizers are used
- always
- on air conditioning systems only
11: R-410A is classified as a ____ refrigerant on the safety matrix.
- B-2
- A-1
- B-1
- A-2
12: A single pole-double throw switch used how many wires excluding the ground wire?
- two
- three
- four
- five
13: The certificate of inspection
- shall be $20 and an additional fee of $1 for each tone above 20 tons
- shall be authorized by a notarized insurance company
- shall be posted on the compressor shell or electrical panel at the unit
- shall be posted and protected from dirt, water, and other elements
14: Low temperature systems should have what?
- High pour point
- Low pour point
- High viscosity
- None of the above
15: Name an HCFC refrigerant(s):
- R-22
- R-123
- R-11
- both a & b
16: Which oil is hydoscopic?
- mineral
- animal
- SW30
- polyolester
17: Most CFC's are
- inert but toxic
- toxic
- flammable
- inert
18: Who is permitted to access a refrigeration machine room?
- Authorized persons only
- Any employee
- Contractors only
- Anyone, it's a completely safe area
19: While the system is operating, the discharge line should be
- too hot to hold by hand
- room temperature
- at the same temperature as the crankcase
- 10-15F warmer than ambient
20: In an air conditioning system, the unit of total heat energy content in an air/vapor mixture is
- Latent heat
- Specific heat
- Sensible heat
- Enthalpy
21: A motor starter contains a thermal overload and a
- contactor
- 3-way relay
- solenoid
- transformer
22: A factory-sealed system containing less than 22lbs. of Group A1 refrigerant
- does not require a pressure-limiting device
- shall have a pressure limiting device installed on the high side of the system
- shall have a pressure limiting device and a pressure relief valve installed
- shall be inspected by the Boiler of Inspectors bi-annually
23: The critical temperature of a refrigerant gas occurs when
- the gas is no longer saturated
- any decrease in pressure will cause condensation
- the gas returns to a liquid
- any increase in pressure will not liquefy the gas
24: Capacitors are rated in
- micro-farads
- megaohms
- kelvins
- volt - amperes
25: Watt's Law indicates Volts X Amps = _________.
- Resistance
- Ohms
- Current
- Watts