Topics: All categories in the pool
1: How are safety controls wired in a circuit?
- Either series or parallel
- Series
- Series/parallel
- Parallel
2: When an electronic bridge is in balance the bridge output will be
- 15 volts
- 1 volt
- 0 volts
- .01 volts
3: What is a high-side float?
- Located in the evaporator, is a float-type metering device that rises to reduce refrigerant flow when the liquid refrigerant level rises in the low side of the chiller
- Located in the liquid line entering the evaporator, is a float-type metering device that rises to reduce refrigerant flow when the liquid refrigerant level rises in the high side of the chiller
- An electronic-type metering device that contains a float assembly within the device which can accurately meter refrigerant into the evaporator as the load varies
- Located in the liquid line entering the evaporator, so when the refrigerant level is higher in the liquid line than the evaporator, the float rises to allow more refrigerant flow into the evaporator
4: What happens after your initial inspection of a pressure vessel?
- Notify the AHJ to let them know that the system been inspected
- Inspector leaves a metal tag with a certification listed on it
- There is a temporary shut-down until a final inspection can be performed.
- Notify the Fire Marshal that the system has been inspected and approved
5: Horizontal piping should be run level.
- True
- False
- No, unless the supervisor on the job says so.
- Yes, if the condenser is located above the evaporator
6: Which creates more of a heat load?
- 30% RH
- 50% RH
- 90% RH
- 70% RH
7: Secondary refrigerants are usually
- alcohol
- water or brine
- Prestone anti-freeze
- expensive
8: The outer portion of shell of the compressor used on low-pressure chillers is called the
- volute
- suction
- nozzle
- baffle
9: What kind of material can't be used on the outlet of a relief valve?
- Copper
- PVC
- Aluminum
- Stainless Steel
10: At higher altitudes, boiling temperatures
- increase
- decrease
- are unaffected
- depends on the refrigerant
11: 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
12: What effect does the temperature of air have on humidity?
- warmer air holds more moisture then cooler air
- cooler air holds more moisture then warmer air
- air has no effect of humidity
- none of the above
13: Dew point is
- the temperature of air of 50% RH
- the temperature above which water vapor in the air will start to condense
- the temperature below which water vapor in the air will start to condense
- the temperature below which water vapor in the air will start to evaporate
14: Excessive head pressure is often caused by
- air cooled condenser is plugged
- insufficient refrigerant
- leaking reed valve on the discharge side
- thermostat set too high
15: A restaurant is classified as a
- public assembly occupancy
- commercial occupancy
- large mercantile occupancy
- mixed occupancy
16: In an air conditioning system, the unit of total heat energy content in an air/vapor mixture is
- Sensible heat
- Latent heat
- Enthalpy
- Specific heat
17: Ohm's Law indicates Amps X Resistance = ___________.
- Volts
- Current
- Ohms
- Impedance
18: Where can 50/50 solder be used on?
- suction line
- liquid line
- discharge line
- none of the above
19: How many gallons of water per pound of ammonia do you need?
- 20
- 15
- 5
- 1
20: Instead of using a compressor, an absorption air-conditioning chiller uses which of the following as its driving force?
- Electricity
- Heat
- Air
- Oil
21: What was the main reason for enacting the no venting rule of July 1, 1992?
- Ozone depletion
- Green house effect
- Global warming potential
- All of the above
22: A check valve is a device
- designed to allow the flow of refrigerant gas in both directions
- that is always spring loaded
- with a pressure drop
- found on high pressure steam systems
23: To determine the pump size needed for an open cooling tower system, the following must be known,
- GPM and friction head
- GPM and balanced head and friction head
- GPM and unbalanced head and friction head
- GPM, pipe size, and equivalent head.
24: What is the boiling point of refrigerant governed by?
- Compressor RPM's
- P&T relationship
- Condenser sub-cooling
- Evaporator temperature
25: Before you change the type of refrigerant in a refrigeration system, what three things must be done?
- you can never change refrigerants
- Make sure its compatible, notify owner, and notify AHJ.
- Nothing must be done
- Place sign, check for leaks, and insulate suction line