Test your basic knowledge |

Residential Air Conditioning

Instructions:

Answer 50 questions in 15 minutes.
If you are not ready to take this test, you can study here.
Match each statement with the correct term.
Don't refresh. All questions and answers are randomly picked and ordered every time you load a test.

This is a study tool. The 3 wrong answers for each question are randomly chosen from answers to other questions. So, you might find at times the answers obvious, but you will see it re-enforces your understanding as you take the test each time.

1. How long should you leave a system off once you kill power before restarting it?
2 minutes
Heat load
On the common terminal
Pi x radius squared

2. How are the condenser coils different on a high-efficiency unit?
8
They are larger
40 degrees F
Subtract ambient temperature from 100

3. How do you calculate EER?
Btu/hr (output) / wattage (input)
Side-by-side and over-and-under
Yes
Inches of water column (in. WC)

4. What are the three pressures created by moving air in ductwork?
Outside diameter (OD)
Static pressure - velocity pressure - and total pressure
TXV
Inside diameter (ID)

5. 8' round duct has a ballpark cfm of what?
200
Belt drive and direct drive
Slugging
Staples and tape

6. What is the typical temperature difference between a standard-efficiency condenser and the ambient temperature?
30 degrees F
In parallel
It rises
Individual return air systems and central return air systems

7. How many amps can 10 g wire handle?
It rises
Outside of the male fitting
30 A
Inside diameter (ID)

8. When do you install a trap on a drain line?
A swaging tool
Over/under and side by side
When it is a pull-through evaporator
TXV

9. What is the typical pressure differance across a TXV?
In series
It rises
Outside of the male fitting
100 psig

10. 13 SEER is classified as what kind of efficiency?
40 A
A piston type metering device
High
Any amount

11. Do you need a vent on a pull-through evaporator?
A piston type metering device
Inches of water column (in. WC)
300
Yes

12. Do you need a trap on a pull-through evaporator?
Any amount
4
Standard
Yes

13. 10 SEER is classified as what kind of efficiency?
A piston type metering device
Before the vent
Standard
40 degrees F

14. What are the two functions of the air-conditioning system?
140 degrees F
To remove humidity and lower dry bulb temperature
400
Static pressure - velocity pressure - and total pressure

15. Where do you apply flux when soldering?
It will have a decrease in superheat
They are physically larger
Blended refrigerants
Outside of the male fitting

16. What are the two types of return air systems in residential installations?
Individual return air systems and central return air systems
A bypass duct or a dump zone
In parallel
30 degrees F

17. How many amps can 14 g wire handle?
L-type
15 A
High
95 degrees F outside - 80 degrees F inside - and 50% relative humidity

18. The fan switch opens at what temperature?
Standard
Stranded
By increasing the surface of the condenser coil
105 degrees F

19. In what state is the refrigerant in the compressor?
Vapor
Individual return air systems and central return air systems
30 degrees F
They are physically larger

20. A reciprocating compressor has what sort of moving parts?
Yes
Compressor
105 degrees F
Pistons

21. What is the typical temperature difference between a high-efficiency condenser and the ambient temperature?
Suction
20 degrees F
L-type
2 minutes

22. The fan switch opens at what temperature?
105 degrees F
Infiltration and ventilation
TXV
Subtract ambient temperature from 100

23. How will too much refrigerant effect superheat?
Over 800 degrees F
2
30-35 degrees above ambient
It will be low

24. What are the two types of blower drives?
True
Pi x radius squared
Belt drive and direct drive
Yes

25. What kind of copper tubing is used for refrigeration or air-conditioning applications?
ACR (air-conditioning refrigeration) tubing
L-type
A bypass duct or a dump zone
Duct - electrical - and mechanical

26. How many amps can 10 g wire handle?
TXV
18 gauge
30 A
S-clips and drives (cleats)

27. How are the high pressure switch and the low pressure switch wired with the compressor contactor?
Yes
Static pressure - velocity pressure - and total pressure
40 degrees F
In series

28. How long should you leave a system off once you kill power before restarting it?
2 minutes
20 degrees above ambient
Belt drive and direct drive
12000

29. Where do you install a trap on a drain line?
They are larger
It also rises
Shorted winding - open winding - and grounded winding
Before the vent

30. 9' round duct has a ballpark cfm of what?
300
Static pressure - velocity pressure - and total pressure
Outside of the male fitting
Compressor

31. 8' round duct has a ballpark cfm of what?
It will be low
200
When it is a pull-through evaporator
Inside diameter (ID)

32. The compressor is cooled by liquid refrigerant. (True of False)
False
Belt drive and direct drive
They are larger
Pull a vacuum

33. How much superheat do you need to prevent liquid refrigerant from entering the compressor?
Any amount
Over/under and side by side
Static pressure - velocity pressure - and total pressure
Nitrogen with a small amount of refrigerant

34. What is used to measure static air pressure in ducts.
Inclined manometer
Inches of water column (in. WC)
20 degrees above ambient
15 A

35. What kind of metering device do high-efficiency units usually use?
Belt drive and direct drive
RLA/FLA x 5
TXV
A piston type metering device

36. How do you achieve high-efficiency?
TXV
TXV
40 degrees F
By increasing the surface of the condenser coil

37. If the rpm's are 3450 - how many poles does the motor have?
2
In parallel
8-12 degrees F
Infiltration and ventilation

38. Square sheet metal duct is normally fabricated in a sheet metal shop and assembled in the field. (True or False)
Heat load
It will be high
True
When it is a pull-through evaporator

39. What is considered normal operating conditions?
15% silphos
2 minutes
75 degrees F dry bulb indoor - 95 degrees F drybulb outdoor - and 50% relative humidity
An air-conditioning system that has all four components (compressor - condenser - metering device - and evaporator) in one housing.

40. The refrigerant within the evaporator will typically boil at what temperature when it is 75 degrees inside with a relative humidity of 50%?
Heat loss
Standard
40 degrees F
Vapor

41. When must a copper joint never be soldered or brazed?
95 degrees F outside - 80 degrees F inside - and 50% relative humidity
When the system is under pressure
12000
45-55%

42. At what temperature does refrigerant condense in a standard-efficiency unit?
Before the vent
To remove humidity and lower dry bulb temperature
30-35 degrees above ambient
Boil the liquid refrigerant out ot the oil within the crankcase

43. What kind of copper tubing is used for plumbing and heating applications?
RLA/FLA x 5
95 degrees F outside - 80 degrees F inside - and 50% relative humidity
In parallel
Nominal-sized tubing

44. How do you calculate EER?
Btu/hr (output) / wattage (input)
Dehydrated with caps on each end
Inches of water column (in. WC)
Slugging

45. What gauge is thermostat wire?
18 gauge
With a minimum of three evenly spaced self-tapping screws
With an are rating
Pi x radius squared

46. How is ACR tubing sized?
It will have a decrease in superheat
Common
Outside diameter (OD)
Fiberglass

47. How many amps can 8 g wire handle?
Nominal-sized tubing
Shorted winding - open winding - and grounded winding
40 A
140 degrees F

48. How do you achieve high-efficiency?
With a minimum of three evenly spaced self-tapping screws
By increasing the surface of the condenser coil
Staples and tape
Vapor

49. Do you need a vent on a pull-through evaporator?
30-35 degrees above ambient
Yes
Heat loss
It also rises

50. How many amps can 8 g wire handle?
Stranded
40 A
Inclined manometer
To keep refrigerant from absorbing heat and to prevent condensation from forming on the line