Topics: All categories in the pool
1: One atmosphere equals
- 29.4
- 14.7
- 0 psig
- 0 psia
2: Pressure is equivalent of
- Force / Area
- Force
- Area X Force
- Force X Area
3: "E" references ____ in the Ohm's law formula
- voltage
- capacitance
- resistance
- amperage
4: If a liquid receiver is designed to receive the refrigerant charge during a pumpdown procedure, it shall have the capacity to
- receive the pumpdown charge
- release the charge when the pressure exceeds 310 psig or higher
- Pumpdown procedures are not allowed with systems containing liquid recievers
- hold up to 110% of the pumpdown charge
5: Transformers are rated in
- volt-amps
- volts
- amps
- volts-ohms
6: Total heat of a substance is considered
- enthalpy
- sensible heat
- empathetical
- specific heat
7: The 4 basic methods of determining whether the proper amount of refrigerant is being introduced into the system are
- sight glass, weight, paper method, and frost line.
- sight glass, weight, pressure, and dipstick
- Buss-eye, weight, pressure, and frost line
- sight glass, weight, pressure, and frost line
8: Sublimation occurs when
- gas is formed from a liquid
- ice melts and turns to water
- gas is formed directly from a solid
- liquid is formed from a gas
9: What is potential measured in?
- Volts
- Amps
- Ohms
- Henrys
10: Where are the three places that the discharge from an ammonia relief valve be piped?
- atmosphere, tank containing water, where the A.H.J. indicates
- underground, into drain, into mechanical room
- to chemical neutralizing tank only
- none of the above
11: Brazed joints melt at temperatures above
- 1,000F
- 500F
- 800F
- 1,200F
12: one BTU equals
- 3.41 hp
- Pi
- 12,000 hp
- 31.4 hp
13: Group A1 refrigerants over ____ pounds in a system must discharge to the atmosphere
- 6.6
- 330
- 110
- 1,000
14: On a day with low relative humidity, the two thermometers on a sling psychrometer will read
- a ling psychrometer doesn't have two theremometers.
- far apart or greater difference
- nearly the same
- 2F difference
15: In an A/C unit, dirty filters will cause
- high suction pressur
- high discharge pressure
- low suction pressure
- low oil pressure
16: A water regulating valve opens when
- the compressor is on
- when the power is on
- when the power is on there is an overcharge of refrigerant
- the head pressure rises
17: 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
18: What is the minimum size of the discharge pipe?
- Same size as the outlet of the relief valve
- One pipe size larger that the inlet of the relief valve
- Depends on size of manifold
- All of the above
19: If a low-pressure chiller has a low-side leak, which of the following will most likely result?
- High head pressure and low suction pressure
- Low suction pressure and low discharge pressure
- High suction pressure and high discharge pressure.
- Low head pressure and high suction pressure
20: R-12 is
- dichlorodifluoromethane
- dichlorofluoromethane
- dichloromethane
- trichlorofluoromethane
21: Absolute pressure is
- Gauge Pressure
- Atmospheric Pressure
- Gauge + Atmospheric Pressure + Pi
- none of the above
22: Which of the following controllers would you expect to be most sensitive to temperature changes?
- low voltage t-stat
- aquastat
- immersion controller
- line voltage t-stat
23: No open flames are allowed in the machinery room unless?
- Approved by the authorized person
- Only when combustion air is provided from outside of the machinery room
- Approved by the installing contractor
- Never can be allowed
24: The total amount of refrigerant stored in a machinery room in all containers not provided with relief valves shall not exceed
- 55 lbs
- 550 lbs
- 660 lbs
- 330 lbs.
25: A hissing noise at the expansion valve is a good indication that
- gas is passing thru it
- nothing is passing thru
- liquid is passing thru it
- expansion valve is oversized