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. 9' round duct has a ballpark cfm of what?
Yes
True
8-12 degrees F
300

2. What is the normal evaporator temperature?
Outside of the male fitting
30 A
45 degrees F
ACR (air-conditioning refrigeration) tubing

3. Most duct insulation is made of what?
100 psig
Fiberglass
Below 800 degrees F
A bypass duct or a dump zone

4. 10' round duct has a ballpark cfm of what?
400
Pistons
With an are rating
High

5. 10' round duct has a ballpark cfm of what?
400
When it is a pull-through evaporator
2 minutes
40 degrees F

6. The fan switch closes at what temperature?
False
140 degrees F
It will have a decrease in superheat
18 gauge

7. How are high-efficiency condenser coils different from standard-efficiency condenser coils?
A piston type metering device
They are physically larger
With 4' saddles
30-35 degrees above ambient

8. How are the condenser coils different on a high-efficiency unit?
Nitrogen with a small amount of refrigerant
Indoor fan motor - outdoor fan motor - and the compressor
They are larger
140 degrees F

9. If pressure rises - what happens to the superheat?
6
Stranded
It rises
Compressor

10. Most duct insulation is made of what?
Fiberglass
400
With a minimum of three evenly spaced self-tapping screws
A band 4 inches or more in width

11. What are the two types of return air systems in residential installations?
A band 4 inches or more in width
Individual return air systems and central return air systems
100
12000

12. 8' round duct has a ballpark cfm of what?
Yes
With a minimum of three evenly spaced self-tapping screws
12000
200

13. 10 SEER is classified as what kind of efficiency?
Indoor fan motor - outdoor fan motor - and the compressor
6
It will have a decrease in superheat
Standard

14. At what temperature does refrigerant condense in a standard-efficiency unit?
Static pressure - velocity pressure - and total pressure
Rise
95 degrees F outside - 80 degrees F inside - and 50% relative humidity
30-35 degrees above ambient

15. What are the two types of blower drives?
40 degrees F
95 degrees F outside - 80 degrees F inside - and 50% relative humidity
Belt drive and direct drive
Subtract ambient temperature from 100

16. Where is insulation used on copper tubing used for air-conditioning?
The suction line or the low-pressure side
Staples and tape
20 degrees above ambient
Shorted winding - open winding - and grounded winding

17. 10 SEER is classified as what kind of efficiency?
Pull a vacuum
Standard
In series
12000

18. What are the three pressures created by moving air in ductwork?
Static pressure - velocity pressure - and total pressure
Stranded
18 gauge
8-12 degrees F

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

20. What can cause a decrease in suction pressure on an air-conditioning system?
A dirty evaporator
A band 4 inches or more in width
Heat loss
75 degrees F dry bulb indoor - 95 degrees F drybulb outdoor - and 50% relative humidity

21. Do you need a vent on a pull-through evaporator?
6
True
Yes
A band 4 inches or more in width

22. What kind of copper tubing is used for plumbing and heating applications?
30 A
40 degrees F
Nominal-sized tubing
Staples and tape

23. What do you do after you braze a system?
45 degrees F
In series
A bypass duct or a dump zone
Pull a vacuum

24. When do you install an auxillary drain pan?
When it is above a conditioned space
Dehydrated with caps on each end
Stranded
Stranded

25. What is lined duct?
Standard
Btu/hr (output) / wattage (input)
TXV
Duct with insulation on the inside

26. How do you calculate LRA?
To remove humidity and lower dry bulb temperature
RLA/FLA x 5
Yes
Yes

27. What kind of copper tubing is used for refrigeration or air-conditioning applications?
Stranded
Pi x radius squared
Before the vent
ACR (air-conditioning refrigeration) tubing

28. What kind of refrigeratnts must be added in liquid form?
4
Blended refrigerants
40 A
Slugging

29. A reciprocating compressor has what sort of moving parts?
Over 800 degrees F
Pistons
A diffuser
S-clips and drives (cleats)

30. How does ACR copper pipe come?
140 degrees F
False
Compressor
Dehydrated with caps on each end

31. Multiple-zone systems often use what to alleviate the problem of excess air when only some zones are calling for conditioning?
Positive
A bypass duct or a dump zone
No
TXV

32. What is the typical temperature difference between a standard-efficiency condenser and the ambient temperature?
30 degrees F
200
S-clips and drives (cleats)
Suction

33. What gauge is thermostat wire?
100 psig
A piston type metering device
18 gauge
A band 4 inches or more in width

34. 13 SEER is classified as what kind of efficiency?
High
It also rises
Staples and tape
Heat load

35. When must a copper joint never be soldered or brazed?
Dehydrated with caps on each end
When the system is under pressure
Vapor
It will be high

36. How do you achieve high-efficiency?
False
Inches of water column (in. WC)
No
By increasing the surface of the condenser coil

37. What are the two functions of the air-conditioning system?
Yes
To remove humidity and lower dry bulb temperature
Standard
30-35 degrees above ambient

38. What kind of copper tubing is used for plumbing and heating applications?
15% silphos
Nominal-sized tubing
Inside diameter (ID)
To keep refrigerant from absorbing heat and to prevent condensation from forming on the line

39. Sections of duct board can be fastened together with what?
Staples and tape
Yes
SEER includes the energy used in the start-up and shut-down cycles
Shorted winding - open winding - and grounded winding

40. What do you do after you braze a system?
18 gauge
200
Pull a vacuum
Inclined manometer

41. In what length rolls is soft copper tubing normally available?
25-ft or 50-ft
Suction
Inches of water column (in. WC)
S-clips and drives (cleats)

42. How many amps can 10 g wire handle?
It rises
Indoor fan motor - outdoor fan motor - and the compressor
30 A
ACR (air-conditioning refrigeration) tubing

43. How do you calculate EER?
1/4'
Any amount
To remove humidity and lower dry bulb temperature
Btu/hr (output) / wattage (input)

44. Why is it necessary to have multiple refrigerant circuits in some evaporator coils?
To lower the amount of pressure drop through the coil
400
To remove humidity and lower dry bulb temperature
15 A

45. At what temperature does refrigerant condense in a standard-efficiency unit?
Outside diameter (OD)
30-35 degrees above ambient
In series
They are physically larger

46. Do you need a trap on a push-through evaporator?
With a minimum of three evenly spaced self-tapping screws
1/4'
No
Nitrogen with a small amount of refrigerant

47. Where do you install a trap on a drain line?
Before the vent
8
6
Boil the liquid refrigerant out ot the oil within the crankcase

48. What is the typical temperature difference between a high-efficiency condenser and the ambient temperature?
A piston type metering device
Latent and sensible
Static pressure - velocity pressure - and total pressure
20 degrees F

49. What kind of metering device do high-efficiency units usually use?
12000
25-ft or 50-ft
TXV
95 degrees F outside - 80 degrees F inside - and 50% relative humidity

50. Does a package unit come from the factory pre-charged?
The suction line or the low-pressure side
Duct - electrical - and mechanical
Potential relay and start capacitor
Yes