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. In what state is the refrigerant in the compressor?
Vapor
ACR (air-conditioning refrigeration) tubing
Duct - electrical - and mechanical
Below 800 degrees F

2. A reciprocating compressor has what sort of moving parts?
With a minimum of three evenly spaced self-tapping screws
Pistons
Over 800 degrees F
30 degrees F

3. What kind of refrigeratnts must be added in liquid form?
25-ft or 50-ft
Blended refrigerants
Slugging
TXV

4. The compressor is cooled by liquid refrigerant. (True of False)
False
A swaging tool
95 degrees F outside - 80 degrees F inside - and 50% relative humidity
Boil the liquid refrigerant out ot the oil within the crankcase

5. What percentage silver do you use to braze two dissimilar metals such as steel and copper?
Inches of water column (in. WC)
Stranded
45-55%
It rises

6. Which is more efficient - a TXV or a fixed-orifice metering device?
Yes
30 A
TXV
400

7. The A/C size is calculated by what?
Yes
Outside diameter (OD)
Heat load
True

8. How long should you leave a system off once you kill power before restarting it?
15 A
2 minutes
Standard
30 A

9. At what temperature does refrigerant condense in a high-efficiency unit?
Duct - electrical - and mechanical
They are physically larger
It also rises
20 degrees above ambient

10. How many amps can 8 g wire handle?
An air-conditioning system that has all four components (compressor - condenser - metering device - and evaporator) in one housing.
40 A
45 degrees F
Duct with insulation on the inside

11. What tool is used to expand the diameter of soft copper tubing
Yes
20 A
A swaging tool
Compressor

12. What percentage silver do you use to braze two dissimilar metals such as steel and copper?
105 degrees F
Pistons
45-55%
Nitrogen with a small amount of refrigerant

13. In what length rolls is soft copper tubing normally available?
When it is a pull-through evaporator
25-ft or 50-ft
Suction
Yes

14. Sections of duct board can be fastened together with what?
With 4' saddles
Indoor fan motor - outdoor fan motor - and the compressor
140 degrees F
Staples and tape

15. How will too much refrigerant effect subcooling?
To keep refrigerant from absorbing heat and to prevent condensation from forming on the line
They are larger
It will be high
Belt drive and direct drive

16. In what length rolls is soft copper tubing normally available?
25-ft or 50-ft
SEER includes the energy used in the start-up and shut-down cycles
Blended refrigerants
When the system is under pressure

17. What do you use to connect square and rectangular ductboard together?
15 A
S-clips and drives (cleats)
Subtract ambient temperature from 100
The suction line or the low-pressure side

18. The evaporator is designed to remove what two types of heat?
Latent and sensible
Pistons
With a minimum of three evenly spaced self-tapping screws
Staples and tape

19. What sort of pressure will a push-through evaporator have?
100
Inches of water column (in. WC)
Positive
No

20. 13 SEER is classified as what kind of efficiency?
When it is above a conditioned space
When the system is under pressure
Compressor
High

21. At what temperature does refrigerant condense in a standard-efficiency unit?
30-35 degrees above ambient
Stranded
When it is above a conditioned space
It will be high

22. When must a copper joint never be soldered or brazed?
25-ft or 50-ft
30 A
When the system is under pressure
When it is above a conditioned space

23. What is the range for normal superheat and subcooling?
Boil the liquid refrigerant out ot the oil within the crankcase
8-12 degrees F
95 degrees F outside - 80 degrees F inside - and 50% relative humidity
20 degrees above ambient

24. Pressure in ductwork is measured In what?
140 degrees F
Average feet per minute X area in square feet (H' x W'/144)
Compressor
Inches of water column (in. WC)

25. What do you use to check for leaks?
It will be low
Nitrogen with a small amount of refrigerant
A piston type metering device
Side-by-side and over-and-under

26. What is the name of the fitting where the branch line leaves the duct?
The takeoff fitting
Fiberglass
Yes
No

27. Where do you check the amps on a motor?
12000
Shorted winding - open winding - and grounded winding
On the common terminal
Yes

28. How are high-efficiency condenser coils different from standard-efficiency condenser coils?
They are physically larger
2
Average feet per minute X area in square feet (H' x W'/144)
45-55%

29. How are the high pressure switch and the low pressure switch wired with the compressor contactor?
15 A
In series
An air-conditioning system that has all four components (compressor - condenser - metering device - and evaporator) in one housing.
False

30. 10 SEER is classified as what kind of efficiency?
They are larger
Potential relay and start capacitor
They are physically larger
Standard

31. What is the design boiling point for most evaporator coils in residential air conditioning?
Staples and tape
No
40 degrees F
Slugging

32. What is lined duct?
Yes
Duct with insulation on the inside
Side-by-side and over-and-under
Duct - electrical - and mechanical

33. How are the condenser coils different on a high-efficiency unit?
Standard
They are larger
Stranded
Duct with insulation on the inside

34. The fan switch opens at what temperature?
In parallel
105 degrees F
Dehydrated with caps on each end
6

35. The load on the evaporater will effect which pressure?
Negative
Suction
ACR (air-conditioning refrigeration) tubing
Negative

36. The load on the evaporater will effect which pressure?
Suction
100 psig
TXV
1/4'

37. How will too much refrigerant effect superheat?
L-type
It will be low
Potential relay and start capacitor
When the system is under pressure

38. 10' round duct has a ballpark cfm of what?
It also rises
Over/under and side by side
400
Positive

39. How does ACR copper pipe come?
40 degrees F
They are physically larger
Over/under and side by side
Dehydrated with caps on each end

40. What type of air conditioning system must be charged using the superheat method?
Duct with insulation on the inside
TXV
A piston type metering device
30-35 degrees above ambient

41. What is the difference between SEER and EER?
Yes
SEER includes the energy used in the start-up and shut-down cycles
It rises
ACR (air-conditioning refrigeration) tubing

42. Can refrigerant line sets be altered in length?
Yes
15 A
It rises
Heat load

43. What are the four materials used to make duct?
Yes
Sheet metal - galvanized sheet metal - fiberglass - and flexduct
With an are rating
Outside diameter (OD)

44. How is ACR tubing sized?
Nitrogen with a small amount of refrigerant
No
Outside diameter (OD)
When it is above a conditioned space

45. Where do you apply flux when soldering?
20 A
It rises
Positive
Outside of the male fitting

46. What are the three major power-consuming devices on an air-conditioning system?
Nominal-sized tubing
Indoor fan motor - outdoor fan motor - and the compressor
Stranded
Belt drive and direct drive

47. The evaporator is designed to remove what two types of heat?
Latent and sensible
Side-by-side and over-and-under
40 A
Blended refrigerants

48. Where is insulation used on copper tubing used for air-conditioning?
S-clips and drives (cleats)
The suction line or the low-pressure side
They are larger
5 degrees

49. What are the two types of blower drives?
True
Belt drive and direct drive
Pull a vacuum
High

50. What do you use to check for leaks?
TXV
Nitrogen with a small amount of refrigerant
100
Outside of the male fitting