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 is the range for normal superheat and subcooling?
8-12 degrees F
Inches of water column (in. WC)
45 degrees F
With a minimum of three evenly spaced self-tapping screws

2. What is the normal evaporator temperature?
When it is above a conditioned space
45 degrees F
Stranded
Yes

3. What is the typical temperature difference between a standard-efficiency condenser and the ambient temperature?
Belt drive and direct drive
Heat loss
30 degrees F
High

4. In what length rolls is soft copper tubing normally available?
25-ft or 50-ft
Nominal-sized tubing
40 A
Blended refrigerants

5. How many cfm per ton?
150
They are physically larger
400
Yes

6. Square sheet metal duct is normally fabricated in a sheet metal shop and assembled in the field. (True or False)
True
150
A swaging tool
Shorted winding - open winding - and grounded winding

7. What is the difference between SEER and EER?
SEER includes the energy used in the start-up and shut-down cycles
Fiberglass
45-55%
Positive

8. When do you install an auxillary drain pan?
Rise
A bypass duct or a dump zone
When it is above a conditioned space
100 psig

9. 13 SEER is classified as what kind of efficiency?
Boil the liquid refrigerant out ot the oil within the crankcase
Slugging
High
Outside diameter (OD)

10. How is ACR tubing sized?
18 gauge
An air-conditioning system that has all four components (compressor - condenser - metering device - and evaporator) in one housing.
S-clips and drives (cleats)
Outside diameter (OD)

11. What is the difference between SEER and EER?
Pull a vacuum
No
SEER includes the energy used in the start-up and shut-down cycles
It will have a decrease in superheat

12. Most duct insulation is made of what?
Static pressure - velocity pressure - and total pressure
A dirty evaporator
Fiberglass
Over 800 degrees F

13. Multiple-zone systems often use what to alleviate the problem of excess air when only some zones are calling for conditioning?
300
Average feet per minute X area in square feet (H' x W'/144)
Over/under and side by side
A bypass duct or a dump zone

14. What is the typical temperature difference between a standard-efficiency condenser and the ambient temperature?
30 degrees F
Outside of the male fitting
Yes
Compressor

15. If pressure rises - what happens to the superheat?
Yes
When it is above a conditioned space
40 degrees F
It rises

16. What sort of pressure will a pull-through evaporator have?
To lower the amount of pressure drop through the coil
Below 800 degrees F
Negative
Positive

17. The fan switch closes at what temperature?
To lower the amount of pressure drop through the coil
95 degrees F outside - 80 degrees F inside - and 50% relative humidity
Latent and sensible
140 degrees F

18. How many amps can 10 g wire handle?
Average feet per minute X area in square feet (H' x W'/144)
20 degrees F
Pi x radius squared
30 A

19. How will too much refrigerant effect subcooling?
140 degrees F
It will be high
40 degrees F
40 A

20. How will an overcharge affect an air-conditioning system with a fixed-orifice type metering device?
Latent and sensible
300
It will have a decrease in superheat
Fiberglass

21. If pressure rises - what happens to the superheat?
Outside of the male fitting
2 minutes
It rises
Infiltration and ventilation

22. What are the two types of return air systems in residential installations?
Potential relay and start capacitor
High
Individual return air systems and central return air systems
On the common terminal

23. If the rpm's are 1750 - how many poles does the motor have?
4
TXV
12000
Yes

24. In what state is the refrigerant in the compressor?
45 degrees F
A bypass duct or a dump zone
Vapor
140 degrees F

25. What are the two functions of the air-conditioning system?
To remove humidity and lower dry bulb temperature
Common
Suction
It will have a decrease in superheat

26. What are the three crafts normally associated with an air-conditioned installation?
Common
Fiberglass
Duct - electrical - and mechanical
A band 4 inches or more in width

27. What tool is used to expand the diameter of soft copper tubing
140 degrees F
A swaging tool
Any amount
100

28. At what temperature does refrigerant condense in a high-efficiency unit?
400
Pi x radius squared
Duct with insulation on the inside
20 degrees above ambient

29. At what temperature does refrigerant condense in a standard-efficiency unit?
TXV
In series
Dehydrated with caps on each end
30-35 degrees above ambient

30. How is the high pressure switch wired with the low pressure switch?
In parallel
100
True
40 degrees F

31. How will too much refrigerant effect superheat?
95 degrees F outside - 80 degrees F inside - and 50% relative humidity
It will be low
Suction
They are physically larger

32. How do you calculate EER?
Static pressure - velocity pressure - and total pressure
Rise
Btu/hr (output) / wattage (input)
Over/under and side by side

33. What standard weight copper tubing is most often used in the heating and air-conditioning industry?
30 A
L-type
5 degrees
Stranded

34. What kind of metering device do high-efficiency units usually use?
Stranded
Rise
20 A
TXV

35. What distributes supply air to a room in a structure?
A diffuser
15% silphos
They are physically larger
To lower the amount of pressure drop through the coil

36. What is the typical temperature difference between a high-efficiency condenser and the ambient temperature?
20 degrees F
40 degrees F
A swaging tool
Sheet metal - galvanized sheet metal - fiberglass - and flexduct

37. The A/C size is calculated by what?
Heat load
300
Yes
1/4'

38. What percentage silver do you need to use for an are-410 system?
With a minimum of three evenly spaced self-tapping screws
They are physically larger
15% silphos
45 degrees F

39. When do you install a trap on a drain line?
Side-by-side and over-and-under
When it is a pull-through evaporator
Outside of the male fitting
It will be low

40. The furnace size is calculated by what?
Heat loss
Pistons
12000
True

41. If the rpm's are 1050 - how many poles does the motor have?
Dehydrated with caps on each end
Over 800 degrees F
20 degrees above ambient
6

42. On what terminal do you check amperage?
A band 4 inches or more in width
Yes
100
Common

43. The compressor is cooled by liquid refrigerant. (True of False)
400
Side-by-side and over-and-under
False
25-ft or 50-ft

44. Why is it necessary to have multiple refrigerant circuits in some evaporator coils?
They are larger
Nominal-sized tubing
To lower the amount of pressure drop through the coil
Yes

45. What percentage silver do you need to use for an are-410 system?
Shorted winding - open winding - and grounded winding
True
Below 800 degrees F
15% silphos

46. Will a dirty condenser cause a rise or fall in pressure?
Positive
Suction
Rise
Nominal-sized tubing

47. Sections of duct board can be fastened together with what?
No
140 degrees F
5 degrees
Staples and tape

48. Which type of wire can handle a higher ampacity?
15% silphos
Stranded
Dehydrated with caps on each end
A diffuser

49. 6' round duct has a ballpark cfm of what?
TXV
75 degrees F dry bulb indoor - 95 degrees F drybulb outdoor - and 50% relative humidity
Yes
100

50. What are the two ways that fresh air enters a structure?
Infiltration and ventilation
Yes
No
6