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. Superheat should never be below how many degrees
Vapor
Dehydrated with caps on each end
Suction
5 degrees

2. What is a package unit?
Duct - electrical - and mechanical
An air-conditioning system that has all four components (compressor - condenser - metering device - and evaporator) in one housing.
Pull a vacuum
20 A

3. What are the components of a hard-start kit?
15% silphos
150
A band 4 inches or more in width
Potential relay and start capacitor

4. Where do you install a trap on a drain line?
Before the vent
150
Nominal-sized tubing
A diffuser

5. How do you calculate EER?
Btu/hr (output) / wattage (input)
Positive
Vapor
20 A

6. What are the three major power-consuming devices on an air-conditioning system?
Yes
Fiberglass
Duct with insulation on the inside
Indoor fan motor - outdoor fan motor - and the compressor

7. How are round ducts supported?

Warning: Invalid argument supplied for foreach() in /var/www/html/basicversity.com/show_quiz.php on line 183

8. What is the typical pressure differance across a TXV?
It will be low
No
100 psig
Yes

9. When do you install a trap on a drain line?
Below 800 degrees F
When it is a pull-through evaporator
40 A
On the common terminal

10. What percentage silver do you use to braze two dissimilar metals such as steel and copper?
Rise
With a minimum of three evenly spaced self-tapping screws
45-55%
400

11. Will a dirty condenser cause a rise or fall in pressure?
400
45 degrees F
Any amount
Rise

12. What standard weight copper tubing is most often used in the heating and air-conditioning industry?
Blended refrigerants
L-type
They are larger
Fiberglass

13. At what temperature will soft solder melt?
Any amount
Before the vent
Below 800 degrees F
4

14. What is considered normal operating conditions?
Heat load
400
75 degrees F dry bulb indoor - 95 degrees F drybulb outdoor - and 50% relative humidity
Duct with insulation on the inside

15. At what temperature does refrigerant condense in a high-efficiency unit?
Yes
20 degrees above ambient
False
45-55%

16. How much does a drain line need to drop per foot of length?

Warning: Invalid argument supplied for foreach() in /var/www/html/basicversity.com/show_quiz.php on line 183

17. Do you need a vent on a push-through evaporator?
It will be low
Pull a vacuum
Yes
With a minimum of three evenly spaced self-tapping screws

18. If the rpm's are 750 - how many poles does the motor have?
Heat load
8
Duct with insulation on the inside
Potential relay and start capacitor

19. What are the four materials used to make duct?
300
95 degrees F outside - 80 degrees F inside - and 50% relative humidity
Sheet metal - galvanized sheet metal - fiberglass - and flexduct
Yes

20. The refrigerant within the evaporator will typically boil at what temperature when it is 75 degrees inside with a relative humidity of 50%?
105 degrees F
Below 800 degrees F
Average feet per minute X area in square feet (H' x W'/144)
40 degrees F

21. If the suction pressure rises - what happens to the head pressure?
It also rises
5 degrees
By increasing the surface of the condenser coil
To keep refrigerant from absorbing heat and to prevent condensation from forming on the line

22. On what terminal do you check amperage?
Vapor
When it is above a conditioned space
2
Common

23. How much superheat do you need to prevent liquid refrigerant from entering the compressor?
No
30 degrees F
A band 4 inches or more in width
Any amount

24. How is insulation around a duct rated?
It rises
To keep refrigerant from absorbing heat and to prevent condensation from forming on the line
With an are rating
Duct with insulation on the inside

25. Where do you check the amps on a motor?
Heat loss
L-type
On the common terminal
Negative

26. What sort of pressure will a pull-through evaporator have?
Vapor
Negative
Latent and sensible
Infiltration and ventilation

27. A reciprocating compressor has what sort of moving parts?
20 degrees F
18 gauge
Pistons
4

28. The fan switch closes at what temperature?
45 degrees F
Individual return air systems and central return air systems
Static pressure - velocity pressure - and total pressure
140 degrees F

29. How is the high pressure switch wired with the low pressure switch?
Indoor fan motor - outdoor fan motor - and the compressor
ACR (air-conditioning refrigeration) tubing
ACR (air-conditioning refrigeration) tubing
In parallel

30. What are the three crafts normally associated with an air-conditioned installation?
Duct - electrical - and mechanical
Side-by-side and over-and-under
To lower the amount of pressure drop through the coil
Pi x radius squared

31. What is the typical temperature difference between a high-efficiency condenser and the ambient temperature?
Shorted winding - open winding - and grounded winding
It will have a decrease in superheat
20 degrees F
105 degrees F

32. How do you calculate cfm?

Warning: Invalid argument supplied for foreach() in /var/www/html/basicversity.com/show_quiz.php on line 183

33. How many amps can 10 g wire handle?
Yes
30 A
30-35 degrees above ambient
200

34. If the rpm's are 1050 - how many poles does the motor have?
Yes
It will be high
200
6

35. How do you calculate cfm?

Warning: Invalid argument supplied for foreach() in /var/www/html/basicversity.com/show_quiz.php on line 183

36. How are the condenser coils different on a high-efficiency unit?
L-type
They are larger
Negative
Nitrogen with a small amount of refrigerant

37. What sort of pressure will a push-through evaporator have?
Common
Positive
20 degrees above ambient
Common

38. How many cfm per ton?
140 degrees F
400
Over/under and side by side
Yes

39. 8' round duct has a ballpark cfm of what?
The takeoff fitting
Over/under and side by side
200
RLA/FLA x 5

40. If the rpm's are 3450 - how many poles does the motor have?
When it is above a conditioned space
400
2
20 degrees F

41. Why are some ACR tubing lines insulated?
When the system is under pressure
TXV
To keep refrigerant from absorbing heat and to prevent condensation from forming on the line
Latent and sensible

42. If pressure rises - what happens to the superheat?
It will be low
It rises
Inclined manometer
4

43. Do you need a vent on a pull-through evaporator?
It will be low
It will be high
Inclined manometer
Yes

44. Sections of duct board can be fastened together with what?
15 A
A swaging tool
8-12 degrees F
Staples and tape

45. What tool is used to expand the diameter of soft copper tubing
18 gauge
By increasing the surface of the condenser coil
A swaging tool
30 degrees F

46. What is it called when liquid refrigerant gets into the compressor?
Yes
Duct with insulation on the inside
Inclined manometer
Slugging

47. 10' round duct has a ballpark cfm of what?
With 4' saddles
150
Boil the liquid refrigerant out ot the oil within the crankcase
400

48. How is nominal-sized tubing sized?
SEER includes the energy used in the start-up and shut-down cycles
Inside diameter (ID)
TXV
25-ft or 50-ft

49. 8' round duct has a ballpark cfm of what?
Heat loss
Standard
200
45-55%

50. What kind of copper tubing is used for refrigeration or air-conditioning applications?
The suction line or the low-pressure side
ACR (air-conditioning refrigeration) tubing
Boil the liquid refrigerant out ot the oil within the crankcase
Potential relay and start capacitor