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. Will a dirty condenser cause a rise or fall in pressure?
18 gauge
40 A
2 minutes
Rise

2. Do you need a vent on a push-through evaporator?
It rises
Yes
Negative
Btu/hr (output) / wattage (input)

3. The crankcase heater on an air-conditioning compressor is used to what?
It rises
L-type
Standard
Boil the liquid refrigerant out ot the oil within the crankcase

4. How do you calculate EER?
Inches of water column (in. WC)
A band 4 inches or more in width
5 degrees
Btu/hr (output) / wattage (input)

5. Square sheet metal duct is normally fabricated in a sheet metal shop and assembled in the field. (True or False)
1/4'
True
No
Infiltration and ventilation

6. Sections of duct board can be fastened together with what?
Staples and tape
It will be low
A band 4 inches or more in width
300

7. What kind of copper tubing is used for plumbing and heating applications?
Nominal-sized tubing
Boil the liquid refrigerant out ot the oil within the crankcase
Duct - electrical - and mechanical
Infiltration and ventilation

8. What can cause a decrease in suction pressure on an air-conditioning system?
Potential relay and start capacitor
A dirty evaporator
Blended refrigerants
15 A

9. At what temperature will brazing melt?
Standard
Over 800 degrees F
Positive
95 degrees F outside - 80 degrees F inside - and 50% relative humidity

10. Superheat should never be below how many degrees
Stranded
Outside diameter (OD)
A bypass duct or a dump zone
5 degrees

11. How is insulation around a duct rated?
Duct - electrical - and mechanical
8
75 degrees F dry bulb indoor - 95 degrees F drybulb outdoor - and 50% relative humidity
With an are rating

12. At what temperature does refrigerant condense in a standard-efficiency unit?
45-55%
Staples and tape
75 degrees F dry bulb indoor - 95 degrees F drybulb outdoor - and 50% relative humidity
30-35 degrees above ambient

13. 9' round duct has a ballpark cfm of what?
Over/under and side by side
With 4' saddles
300
Inches of water column (in. WC)

14. 13 SEER is classified as what kind of efficiency?
30 degrees F
Nitrogen with a small amount of refrigerant
High
100 psig

15. How does ACR copper pipe come?
Belt drive and direct drive
Vapor
Dehydrated with caps on each end
Stranded

16. What are the four materials used to make duct?
A band 4 inches or more in width
Yes
Heat load
Sheet metal - galvanized sheet metal - fiberglass - and flexduct

17. How is the high pressure switch wired with the low pressure switch?
45-55%
High
In parallel
20 degrees F

18. Does a package unit come from the factory pre-charged?
They are physically larger
RLA/FLA x 5
Yes
100

19. How many BTU's per ton?
Rise
Dehydrated with caps on each end
12000
Stranded

20. How do you achieve high-efficiency?
By increasing the surface of the condenser coil
They are physically larger
Slugging
Outside diameter (OD)

21. How do you calculate the area of a circle?
Yes
400
Pi x radius squared
It will be low

22. What are the two types of package units?
Side-by-side and over-and-under
20 A
Average feet per minute X area in square feet (H' x W'/144)
300

23. What are normal conditions - as defined by the ARI.
Pull a vacuum
A band 4 inches or more in width
95 degrees F outside - 80 degrees F inside - and 50% relative humidity
Individual return air systems and central return air systems

24. How do you calculate the area of a circle?
RLA/FLA x 5
Yes
Pi x radius squared
95 degrees F outside - 80 degrees F inside - and 50% relative humidity

25. If the rpm's are 3450 - how many poles does the motor have?
RLA/FLA x 5
400
2
With an are rating

26. What standard weight copper tubing is most often used in the heating and air-conditioning industry?
Yes
No
L-type
Standard

27. On what terminal do you check amperage?
SEER includes the energy used in the start-up and shut-down cycles
Latent and sensible
Over 800 degrees F
Common

28. Which type of wire can handle a higher ampacity?
Btu/hr (output) / wattage (input)
Inclined manometer
Compressor
Stranded

29. What are the components of a hard-start kit?
Dehydrated with caps on each end
Any amount
Potential relay and start capacitor
Before the vent

30. What are normal conditions - as defined by the ARI.
95 degrees F outside - 80 degrees F inside - and 50% relative humidity
Nitrogen with a small amount of refrigerant
40 A
Outside of the male fitting

31. How long should you leave a system off once you kill power before restarting it?
Negative
140 degrees F
2 minutes
Standard

32. When must a copper joint never be soldered or brazed?
When the system is under pressure
With a minimum of three evenly spaced self-tapping screws
Below 800 degrees F
140 degrees F

33. What are the two ways that fresh air enters a structure?
Infiltration and ventilation
When it is a pull-through evaporator
Inclined manometer
To keep refrigerant from absorbing heat and to prevent condensation from forming on the line

34. What do you use to connect square and rectangular ductboard together?
A diffuser
30-35 degrees above ambient
True
S-clips and drives (cleats)

35. What are the three crafts normally associated with an air-conditioned installation?
Suction
Rise
Before the vent
Duct - electrical - and mechanical

36. At what temperature will soft solder melt?
Below 800 degrees F
30 degrees F
45-55%
Pull a vacuum

37. What is it called when liquid refrigerant gets into the compressor?
300
Slugging
Latent and sensible
They are physically larger

38. The evaporator is designed to remove what two types of heat?
Nitrogen with a small amount of refrigerant
Heat load
Latent and sensible
Sheet metal - galvanized sheet metal - fiberglass - and flexduct

39. If the rpm's are 1050 - how many poles does the motor have?
105 degrees F
Shorted winding - open winding - and grounded winding
6
In parallel

40. How is ACR tubing sized?
Outside diameter (OD)
Standard
Slugging
Vapor

41. What are the two basic duct connection configurations for package units supply and return air ducts?
A band 4 inches or more in width
20 degrees F
Yes
Over/under and side by side

42. What sort of pressure will a push-through evaporator have?
Boil the liquid refrigerant out ot the oil within the crankcase
8-12 degrees F
Positive
By increasing the surface of the condenser coil

43. What percentage silver do you use to braze two dissimilar metals such as steel and copper?
75 degrees F dry bulb indoor - 95 degrees F drybulb outdoor - and 50% relative humidity
TXV
45-55%
Common

44. What kind of metering device do high-efficiency units usually use?
When it is a pull-through evaporator
25-ft or 50-ft
TXV
Yes

45. What are the two types of return air systems in residential installations?
300
Yes
Heat loss
Individual return air systems and central return air systems

46. The furnace size is calculated by what?
RLA/FLA x 5
1/4'
Over 800 degrees F
Heat loss

47. The furnace size is calculated by what?
Heat loss
100
150
When it is above a conditioned space

48. Sections of duct board can be fastened together with what?
Staples and tape
Yes
It also rises
With 4' saddles

49. The evaporator is designed to remove what two types of heat?
TXV
Latent and sensible
Over 800 degrees F
It will have a decrease in superheat

50. What percentage silver do you need to use for an are-410 system?
18 gauge
Yes
A swaging tool
15% silphos