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. If the rpm's are 3450 - how many poles does the motor have?
20 degrees F
They are larger
2
Duct - electrical - and mechanical

2. What is the normal evaporator temperature?
Over/under and side by side
200
45 degrees F
12000

3. If pressure rises - what happens to the superheat?
20 degrees above ambient
It rises
18 gauge
Heat loss

4. What is the typical temperature difference between a standard-efficiency condenser and the ambient temperature?
Yes
20 degrees above ambient
Fiberglass
30 degrees F

5. The A/C size is calculated by what?
Indoor fan motor - outdoor fan motor - and the compressor
100
With a minimum of three evenly spaced self-tapping screws
Heat load

6. What kind of refrigeratnts must be added in liquid form?
Average feet per minute X area in square feet (H' x W'/144)
Boil the liquid refrigerant out ot the oil within the crankcase
The suction line or the low-pressure side
Blended refrigerants

7. How do you calculate EER?
Duct - electrical - and mechanical
RLA/FLA x 5
It will be high
Btu/hr (output) / wattage (input)

8. If the rpm's are 750 - how many poles does the motor have?
8
Standard
Shorted winding - open winding - and grounded winding
15% silphos

9. What do you use to check for leaks?
Nitrogen with a small amount of refrigerant
105 degrees F
Inclined manometer
A band 4 inches or more in width

10. The evaporator is designed to remove what two types of heat?
Before the vent
An air-conditioning system that has all four components (compressor - condenser - metering device - and evaporator) in one housing.
By increasing the surface of the condenser coil
Latent and sensible

11. If the suction pressure rises - what happens to the head pressure?
Dehydrated with caps on each end
It also rises
200
Inches of water column (in. WC)

12. What standard weight copper tubing is most often used in the heating and air-conditioning industry?
400
L-type
It also rises
20 degrees F

13. The A/C size is calculated by what?
Boil the liquid refrigerant out ot the oil within the crankcase
Heat load
In parallel
Yes

14. At what temperature will soft solder melt?
Below 800 degrees F
Positive
Over/under and side by side
A swaging tool

15. What are the three crafts normally associated with an air-conditioned installation?
12000
Outside diameter (OD)
Yes
Duct - electrical - and mechanical

16. Do you need a vent on a push-through evaporator?
They are physically larger
Pistons
A dirty evaporator
Yes

17. What are the three pressures created by moving air in ductwork?
Static pressure - velocity pressure - and total pressure
Nominal-sized tubing
Boil the liquid refrigerant out ot the oil within the crankcase
RLA/FLA x 5

18. What tool is used to expand the diameter of soft copper tubing
Fiberglass
The takeoff fitting
In parallel
A swaging tool

19. Most duct insulation is made of what?
400
12000
Fiberglass
A bypass duct or a dump zone

20. What can cause a decrease in suction pressure on an air-conditioning system?
They are physically larger
Positive
A dirty evaporator
It will be low

21. 13 SEER is classified as what kind of efficiency?
Common
Pi x radius squared
8-12 degrees F
High

22. How do you calculate the area of a circle?
Pi x radius squared
Positive
High
TXV

23. How many amps can 14 g wire handle?
30 degrees F
20 degrees F
15 A
To remove humidity and lower dry bulb temperature

24. How is flexible duct supported?
With an are rating
A band 4 inches or more in width
Side-by-side and over-and-under
40 degrees F

25. Multiple-zone systems often use what to alleviate the problem of excess air when only some zones are calling for conditioning?
A bypass duct or a dump zone
A piston type metering device
They are larger
Fiberglass

26. Where do you install a trap on a drain line?
Before the vent
Shorted winding - open winding - and grounded winding
Fiberglass
Standard

27. What is it called when liquid refrigerant gets into the compressor?
Suction
Individual return air systems and central return air systems
Slugging
Inclined manometer

28. If the rpm's are 750 - how many poles does the motor have?
8
The suction line or the low-pressure side
Over/under and side by side
With a minimum of three evenly spaced self-tapping screws

29. What are the two ways that fresh air enters a structure?
Infiltration and ventilation
150
Outside diameter (OD)
RLA/FLA x 5

30. How is flexible duct supported?
Positive
They are larger
400
A band 4 inches or more in width

31. Do you need a trap on a push-through evaporator?
45 degrees F
No
When it is a pull-through evaporator
RLA/FLA x 5

32. What is used to measure static air pressure in ducts.
30 A
Belt drive and direct drive
Subtract ambient temperature from 100
Inclined manometer

33. Can refrigerant line sets be altered in length?
Subtract ambient temperature from 100
Yes
200
75 degrees F dry bulb indoor - 95 degrees F drybulb outdoor - and 50% relative humidity

34. What is the typical temperature difference between a high-efficiency condenser and the ambient temperature?
It also rises
20 degrees F
25-ft or 50-ft
Outside diameter (OD)

35. 10 SEER is classified as what kind of efficiency?
200
18 gauge
Standard
Dehydrated with caps on each end

36. How do you calculate LRA?
RLA/FLA x 5
Duct with insulation on the inside
Potential relay and start capacitor
Infiltration and ventilation

37. What component changes refrigerant from a low pressure gas to a high pressure gas?
Compressor
Btu/hr (output) / wattage (input)
45-55%
Any amount

38. How many amps can 8 g wire handle?
It rises
On the common terminal
40 A
A piston type metering device

39. How many amps can 10 g wire handle?
15 A
Belt drive and direct drive
30 A
ACR (air-conditioning refrigeration) tubing

40. 10' round duct has a ballpark cfm of what?
400
Indoor fan motor - outdoor fan motor - and the compressor
75 degrees F dry bulb indoor - 95 degrees F drybulb outdoor - and 50% relative humidity
300

41. If the rpm's are 1050 - how many poles does the motor have?
Nominal-sized tubing
6
Heat loss
Pull a vacuum

42. The fan switch closes at what temperature?
140 degrees F
They are physically larger
Yes
Dehydrated with caps on each end

43. On what terminal do you check amperage?
Common
Inclined manometer
They are physically larger
95 degrees F outside - 80 degrees F inside - and 50% relative humidity

44. How will too much refrigerant effect subcooling?
It will be high
Inside diameter (ID)
15 A
20 degrees F

45. The fan switch closes at what temperature?
On the common terminal
140 degrees F
They are larger
25-ft or 50-ft

46. Where is insulation used on copper tubing used for air-conditioning?
To keep refrigerant from absorbing heat and to prevent condensation from forming on the line
Boil the liquid refrigerant out ot the oil within the crankcase
The suction line or the low-pressure side
TXV

47. Do you need a vent on a pull-through evaporator?
Standard
2 minutes
A diffuser
Yes

48. Where do you apply flux when soldering?
Outside of the male fitting
100 psig
Pi x radius squared
No

49. 13 SEER is classified as what kind of efficiency?
High
RLA/FLA x 5
True
SEER includes the energy used in the start-up and shut-down cycles

50. If the rpm's are 3450 - how many poles does the motor have?
Vapor
Duct with insulation on the inside
False
2