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. What distributes supply air to a room in a structure?
High
Positive
With a minimum of three evenly spaced self-tapping screws
A diffuser

2. In what length rolls is soft copper tubing normally available?
In series
Outside of the male fitting
RLA/FLA x 5
25-ft or 50-ft

3. Will a dirty condenser cause a rise or fall in pressure?
On the common terminal
Rise
4
True

4. How long should you leave a system off once you kill power before restarting it?
Compressor
Pull a vacuum
2 minutes
True

5. How many amps can 8 g wire handle?
TXV
40 A
45-55%
140 degrees F

6. 13 SEER is classified as what kind of efficiency?
By increasing the surface of the condenser coil
High
Slugging
Outside diameter (OD)

7. What are the three crafts normally associated with an air-conditioned installation?
SEER includes the energy used in the start-up and shut-down cycles
With 4' saddles
Inclined manometer
Duct - electrical - and mechanical

8. What are the two functions of the air-conditioning system?
Blended refrigerants
With 4' saddles
To remove humidity and lower dry bulb temperature
The suction line or the low-pressure side

9. What do you use to check for leaks?
Nitrogen with a small amount of refrigerant
1/4'
The suction line or the low-pressure side
To remove humidity and lower dry bulb temperature

10. Sections of duct board can be fastened together with what?
Before the vent
Staples and tape
It will be high
105 degrees F

11. Will a dirty condenser cause a rise or fall in pressure?
Rise
Yes
Over/under and side by side
Slugging

12. The fan switch closes at what temperature?
S-clips and drives (cleats)
Pistons
75 degrees F dry bulb indoor - 95 degrees F drybulb outdoor - and 50% relative humidity
140 degrees F

13. Where is insulation used on copper tubing used for air-conditioning?
The suction line or the low-pressure side
20 A
2 minutes
False

14. What is it called when liquid refrigerant gets into the compressor?
On the common terminal
Slugging
ACR (air-conditioning refrigeration) tubing
With 4' saddles

15. What standard weight copper tubing is most often used in the heating and air-conditioning industry?
It will be low
L-type
Nitrogen with a small amount of refrigerant
400

16. Why are some ACR tubing lines insulated?
To keep refrigerant from absorbing heat and to prevent condensation from forming on the line
To lower the amount of pressure drop through the coil
With 4' saddles
When it is above a conditioned space

17. At what temperature does refrigerant condense in a standard-efficiency unit?
8-12 degrees F
30-35 degrees above ambient
30 A
Indoor fan motor - outdoor fan motor - and the compressor

18. What are the two types of return air systems in residential installations?
Individual return air systems and central return air systems
It rises
Dehydrated with caps on each end
On the common terminal

19. 7' round duct has a ballpark cfm of what?
Dehydrated with caps on each end
25-ft or 50-ft
150
Rise

20. Most duct insulation is made of what?
Fiberglass
When the system is under pressure
TXV
The suction line or the low-pressure side

21. How will too much refrigerant effect subcooling?
It will be low
It will be high
18 gauge
30 A

22. How many amps can 10 g wire handle?
1/4'
30 A
To lower the amount of pressure drop through the coil
Boil the liquid refrigerant out ot the oil within the crankcase

23. At what temperature will brazing melt?
Over 800 degrees F
200
Inside diameter (ID)
A piston type metering device

24. In what length rolls is soft copper tubing normally available?
25-ft or 50-ft
Subtract ambient temperature from 100
140 degrees F
It will have a decrease in superheat

25. What is used to measure static air pressure in ducts.
15% silphos
The takeoff fitting
Inclined manometer
Average feet per minute X area in square feet (H' x W'/144)

26. How is flexible duct supported?
A band 4 inches or more in width
On the common terminal
It will be high
To keep refrigerant from absorbing heat and to prevent condensation from forming on the line

27. The crankcase heater on an air-conditioning compressor is used to what?
Yes
Boil the liquid refrigerant out ot the oil within the crankcase
45-55%
8-12 degrees F

28. How is flexible duct supported?
25-ft or 50-ft
A band 4 inches or more in width
Static pressure - velocity pressure - and total pressure
They are larger

29. How many cfm per ton?
45-55%
400
30 degrees F
It rises

30. Does a package unit come from the factory pre-charged?
Yes
150
Yes
20 degrees F

31. Why are some ACR tubing lines insulated?
30-35 degrees above ambient
Pi x radius squared
With an are rating
To keep refrigerant from absorbing heat and to prevent condensation from forming on the line

32. What are normal conditions - as defined by the ARI.
Nominal-sized tubing
200
It will have a decrease in superheat
95 degrees F outside - 80 degrees F inside - and 50% relative humidity

33. What are the four materials used to make duct?
Individual return air systems and central return air systems
15% silphos
With a minimum of three evenly spaced self-tapping screws
Sheet metal - galvanized sheet metal - fiberglass - and flexduct

34. If the suction pressure rises - what happens to the head pressure?
Inside diameter (ID)
It also rises
They are larger
To keep refrigerant from absorbing heat and to prevent condensation from forming on the line

35. What is the name of the fitting where the branch line leaves the duct?
The suction line or the low-pressure side
False
100
The takeoff fitting

36. At what temperature will soft solder melt?
150
In series
400
Below 800 degrees F

37. What are the components of a hard-start kit?
Sheet metal - galvanized sheet metal - fiberglass - and flexduct
Potential relay and start capacitor
Boil the liquid refrigerant out ot the oil within the crankcase
The takeoff fitting

38. How do you calculate ballpark superheat?
They are physically larger
To keep refrigerant from absorbing heat and to prevent condensation from forming on the line
Subtract ambient temperature from 100
Heat load

39. What can cause a decrease in suction pressure on an air-conditioning system?
A dirty evaporator
TXV
20 degrees above ambient
400

40. What tool is used to expand the diameter of soft copper tubing
Rise
A swaging tool
To remove humidity and lower dry bulb temperature
Inside diameter (ID)

41. What sort of pressure will a push-through evaporator have?
It will have a decrease in superheat
L-type
45 degrees F
Positive

42. If the rpm's are 750 - how many poles does the motor have?
8
Before the vent
Yes
Yes

43. What component changes refrigerant from a low pressure gas to a high pressure gas?
30 A
Compressor
With 4' saddles
2

44. Where do you install a trap on a drain line?
Before the vent
With a minimum of three evenly spaced self-tapping screws
Side-by-side and over-and-under
Slugging

45. What are the two ways that fresh air enters a structure?
A band 4 inches or more in width
Duct with insulation on the inside
Side-by-side and over-and-under
Infiltration and ventilation

46. What is the design boiling point for most evaporator coils in residential air conditioning?
40 degrees F
Negative
With 4' saddles
20 degrees F

47. What percentage silver do you need to use for an are-410 system?
Over/under and side by side
15% silphos
Pistons
Negative

48. How are the condenser coils different on a high-efficiency unit?
They are larger
By increasing the surface of the condenser coil
A diffuser
20 A

49. What are the three major power-consuming devices on an air-conditioning system?
Indoor fan motor - outdoor fan motor - and the compressor
Yes
18 gauge
400

50. What are the two basic duct connection configurations for package units supply and return air ducts?
To remove humidity and lower dry bulb temperature
5 degrees
100 psig
Over/under and side by side