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. Why are some ACR tubing lines insulated?
Rise
The suction line or the low-pressure side
To keep refrigerant from absorbing heat and to prevent condensation from forming on the line
Potential relay and start capacitor

2. What percentage silver do you need to use for an are-410 system?
Duct - electrical - and mechanical
Negative
15% silphos
18 gauge

3. What are the four materials used to make duct?
Sheet metal - galvanized sheet metal - fiberglass - and flexduct
140 degrees F
Nitrogen with a small amount of refrigerant
Pistons

4. What gauge is thermostat wire?
A diffuser
18 gauge
40 degrees F
Outside diameter (OD)

5. What are the components of a hard-start kit?
Potential relay and start capacitor
Suction
A piston type metering device
SEER includes the energy used in the start-up and shut-down cycles

6. The A/C size is calculated by what?
Heat load
2
Individual return air systems and central return air systems
200

7. What type of air conditioning system must be charged using the superheat method?
It also rises
A piston type metering device
Individual return air systems and central return air systems
Blended refrigerants

8. The refrigerant within the evaporator will typically boil at what temperature when it is 75 degrees inside with a relative humidity of 50%?
300
2
Pistons
40 degrees F

9. How many amps can 12 g wire handle?
20 A
18 gauge
30 A
45 degrees F

10. How many amps can 14 g wire handle?
Negative
Pistons
15 A
45 degrees F

11. What is used to measure static air pressure in ducts.
A diffuser
The suction line or the low-pressure side
40 degrees F
Inclined manometer

12. How is flexible duct supported?
SEER includes the energy used in the start-up and shut-down cycles
A band 4 inches or more in width
Belt drive and direct drive
Sheet metal - galvanized sheet metal - fiberglass - and flexduct

13. What kind of copper tubing is used for refrigeration or air-conditioning applications?
Yes
ACR (air-conditioning refrigeration) tubing
A dirty evaporator
2

14. What is a package unit?
An air-conditioning system that has all four components (compressor - condenser - metering device - and evaporator) in one housing.
A bypass duct or a dump zone
5 degrees
Vapor

15. 7' round duct has a ballpark cfm of what?
Outside diameter (OD)
With an are rating
150
95 degrees F outside - 80 degrees F inside - and 50% relative humidity

16. What do you use to check for leaks?
A piston type metering device
Nitrogen with a small amount of refrigerant
S-clips and drives (cleats)
Individual return air systems and central return air systems

17. What kind of refrigeratnts must be added in liquid form?
1/4'
100 psig
Slugging
Blended refrigerants

18. What sort of pressure will a push-through evaporator have?
Infiltration and ventilation
S-clips and drives (cleats)
Positive
With a minimum of three evenly spaced self-tapping screws

19. How are the condenser coils different on a high-efficiency unit?
It also rises
They are physically larger
They are larger
TXV

20. What percentage silver do you use to braze two dissimilar metals such as steel and copper?
The takeoff fitting
45-55%
Nominal-sized tubing
To lower the amount of pressure drop through the coil

21. Multiple-zone systems often use what to alleviate the problem of excess air when only some zones are calling for conditioning?
Over/under and side by side
False
Vapor
A bypass duct or a dump zone

22. If the suction pressure rises - what happens to the head pressure?
4
False
It also rises
Standard

23. How is insulation around a duct rated?
Inside diameter (ID)
Heat loss
With an are rating
Subtract ambient temperature from 100

24. 10' round duct has a ballpark cfm of what?
Common
25-ft or 50-ft
400
TXV

25. What is the range for normal superheat and subcooling?
Rise
To lower the amount of pressure drop through the coil
8-12 degrees F
Infiltration and ventilation

26. What is the range for normal superheat and subcooling?
8-12 degrees F
Compressor
140 degrees F
When it is above a conditioned space

27. How many cfm per ton?
Common
Standard
Any amount
400

28. How do you calculate EER?
20 A
Btu/hr (output) / wattage (input)
45-55%
40 degrees F

29. 6' round duct has a ballpark cfm of what?
S-clips and drives (cleats)
100
Infiltration and ventilation
100 psig

30. How is nominal-sized tubing sized?
Inside diameter (ID)
When the system is under pressure
5 degrees
With 4' saddles

31. Sections of duct board can be fastened together with what?
In parallel
20 degrees F
Staples and tape
18 gauge

32. On what terminal do you check amperage?
Common
Duct - electrical - and mechanical
Inclined manometer
A swaging tool

33. What sort of pressure will a pull-through evaporator have?
15% silphos
It will be low
It rises
Negative

34. The evaporator is designed to remove what two types of heat?
75 degrees F dry bulb indoor - 95 degrees F drybulb outdoor - and 50% relative humidity
Latent and sensible
300
105 degrees F

35. What do you use to connect square and rectangular ductboard together?
S-clips and drives (cleats)
When it is above a conditioned space
It also rises
300

36. What are normal conditions - as defined by the ARI.
40 degrees F
8-12 degrees F
Outside diameter (OD)
95 degrees F outside - 80 degrees F inside - and 50% relative humidity

37. The fan switch closes at what temperature?
Inside diameter (ID)
Blended refrigerants
140 degrees F
Static pressure - velocity pressure - and total pressure

38. 10 SEER is classified as what kind of efficiency?
20 degrees F
Standard
It will be low
45 degrees F

39. Pressure in ductwork is measured In what?
High
Pull a vacuum
TXV
Inches of water column (in. WC)

40. Superheat should never be below how many degrees
5 degrees
15% silphos
Fiberglass
Yes

41. At what temperature does refrigerant condense in a high-efficiency unit?
1/4'
Static pressure - velocity pressure - and total pressure
20 degrees above ambient
Rise

42. What are the three crafts normally associated with an air-conditioned installation?
Duct - electrical - and mechanical
100 psig
Outside of the male fitting
A piston type metering device

43. How many amps can 8 g wire handle?
45-55%
40 A
Fiberglass
Yes

44. How do you calculate the area of a circle?
30-35 degrees above ambient
12000
Yes
Pi x radius squared

45. Where do you apply flux when soldering?
No
Belt drive and direct drive
15 A
Outside of the male fitting

46. At what temperature does refrigerant condense in a high-efficiency unit?
Pull a vacuum
300
20 degrees above ambient
Staples and tape

47. What is the typical temperature difference between a standard-efficiency condenser and the ambient temperature?
30 degrees F
High
An air-conditioning system that has all four components (compressor - condenser - metering device - and evaporator) in one housing.
2 minutes

48. When do you install a trap on a drain line?
When it is a pull-through evaporator
Yes
30-35 degrees above ambient
When it is above a conditioned space

49. What are the two types of blower drives?
140 degrees F
Slugging
400
Belt drive and direct drive

50. How are the condenser coils different on a high-efficiency unit?
30 A
Indoor fan motor - outdoor fan motor - and the compressor
Compressor
They are larger