Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Unit 14 > Unit 14 Quiz > Flashcards

Unit 14 Quiz Flashcards

1
Q

Wired in parallel with the cooling contacts and is energized during the off cycle.

A

Cold anticipator

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

High and low pressure controls built in one housing.

A

Dual pressure controls

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Mercury rapidly makes or breaks the electrical current flow.

A

Snap or detent action

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Stationary part of the valve that the movable part comes in contact with to stop the flow of fluids.

A

Valve seat

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Point or pressure setting at which the electrical circuit is made.

A

Cut-in

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Liquid and vapor states of matter.

A

Fluid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Bimetal device used to sense fast moving air streams in duct work and furnace heat exchangers.

A

Snap disc

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Requires large diaphragms to sense very low pressures in air systems. Used in air duct to sense blower air before heat is activated.

A

Air pressure control

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Detects presence of gas pressure in gas burning equipment before burners are allowed to ignite.

A

Gas pressure switch

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Normally regulates other controls and does not carry much current (2A max).

A

Low voltage thermostat

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Device used to detect temperature.

A

Temperature sensor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Safety device used on boilers to release excess pressure.

A

Boiler relief valve

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Device used to control the temperature of a space.

A

Space heat/cool thermostat

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Used to start or stop electrical loads such as motors.

A

Pressure switch

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

A Thermostat that monitors motor temperature and shuts it off so it will not overheat.

A

Motor temperature sensing thermostat

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Bimetal formed into a specific shape that provides longer travel when heated.

A

Helix coil

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Heavy duty but not as sensitive or as fast acting as low voltage type when larger current carrying capacities are needed.

A

Line voltage thermostat

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Glass bulb containing a small amount of mercury and electrical contacts used to make or break the electrical circuit in a low voltage thermostat.

A

Mercury bulb

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Customer said the air conditioner doesn’t come on when she turns the switch on the thermostat to the ON position. You check to see if the thermostat is getting power from the transformer by pulling the face plate off the subbed and place your meter test probes on what terminals?

A

Terminals “R” and “C”

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

True or false: An air pressure control can be used to initiate a defrost cycle on the outdoor coil of a heat pump.

A

True

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

True or false: A low pressure control is commonly used on the air conditioning field as a low charge protection device.

A

True

22
Q

True or false: Non-condensable gas in a system can cause high head/discharge pressures.

A

True

23
Q

True or false: Changing the differential does not affect cut-in or cut-out.

A

False

24
Q

True or false: Compressor discharge pressure subtracted from the oil pump outlet pressure equals net oil pressure. (Crankcase)

A

False

25
Q

True or false: The correct way to get good contact when mounting a sensing bulb to a suction line is to clean the surface of oxidation with sand cloth or a wire brush and then mount the bulb using a metal strap and then insulate from the ambient air.

A

True

26
Q

True or false: If the resistance of a compressor motor winding from C to R and C to S reads OL, there is a possibility that the internal overload may have functioned. To confirm, the meter reading from R to S will show a measurable resistance.

A

True

27
Q

True or false: Line voltage thermostats are not designed to handle more than 25A because they would physically be too large.

A

True

28
Q

True or false: The fixed resistor in the cooling anticipator circuit is only energized during the off cycle

A

True

29
Q

True or false: The heating thermostat closes on the rise in temperature.

A

False

30
Q

True or false: A contactor is an electromechanical device.

A

True

31
Q

True or false: Temperature swing includes system overshoot and system lag.

A

True

32
Q

True or false: Digital thermostats do not have adjustable heat anticipator.

A

True

33
Q

True or false: Oil pump inlet pressure is the same as the suction pressure.

A

True

34
Q

Pressure switch Normally open, closes on the fall.

A

C

35
Q

Pressure switch Normally Open, closes on the rise

A

A

36
Q

Pressure switch Normally Closed, opens on the fall.

A

B

37
Q

Pressure switch Normally Closed, opens on the rise.

A

D

38
Q

A cooling thermostat has a cut-in setting of 35 F . The differential is 5 F. What is the cut-out temperature?

A

30 F

39
Q

Technician A says that a pressure transducer has two wires and is normally open. Technician B says that a pressure transducer has three wires, one for power, one for communication and one for ground. Which technician is correct?

A

Technician A and Technician B are both incorrect.

40
Q

A low refrigerant charge in a system that uses a hermetic compressor will cause

A

High head pressures
High compression ratios
High discharge temperatures and low efficiencies

41
Q

Time delay before the oil safety pressure control activates is ______.

A

90 seconds

42
Q

What are two basic applications that water regulating valves are used for?

A
  • Regulates water pressure flow
  • Regulates Head Pressure
43
Q

Determine if the control is mechanical (M) or electromechanical (EM).

______ contactor

A

EM

44
Q

Determine if the control is mechanical (M) or electromechanical (EM).
___ relay

A

EM

45
Q

Determine if the control is mechanical (M) or electromechanical (EM).

_____water pressure regulator

A

M

46
Q

Determine if the control is mechanical (M) or electromechanical (EM).

____ magnetic starter

A

EM

47
Q

Determine if the control is mechanical (M) or electromechanical (EM).

______ Thermal expansion valve (TXV)

A

M

48
Q

Determine if the control is mechanical (M) or electromechanical (EM).

____ pneumatic thermostat

A

M

49
Q

Determine if the control is mechanical (M) or electromechanical (EM).

_____ liquid line solenoid

A

EM

50
Q

Determine if the control is mechanical (M) or electromechanical (EM).

____ Mercury bulb thermostat

A

M

Unit 14 (1 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions