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. How is the high pressure switch wired with the low pressure switch?
Staples and tape
15 A
In parallel
Yes

2. The A/C size is calculated by what?
Heat load
Latent and sensible
Infiltration and ventilation
Yes

3. What are the two types of return air systems in residential installations?
When it is above a conditioned space
Individual return air systems and central return air systems
With 4' saddles
5 degrees

4. What are the two types of return air systems in residential installations?
In series
Potential relay and start capacitor
Individual return air systems and central return air systems
Infiltration and ventilation

5. What distributes supply air to a room in a structure?
A diffuser
30 degrees F
Heat load
Boil the liquid refrigerant out ot the oil within the crankcase

6. How do you calculate LRA?
15% silphos
RLA/FLA x 5
12000
Yes

7. The furnace size is calculated by what?
Side-by-side and over-and-under
Yes
To lower the amount of pressure drop through the coil
Heat loss

8. How do you calculate EER?
It will be low
Btu/hr (output) / wattage (input)
300
SEER includes the energy used in the start-up and shut-down cycles

9. What are the two basic duct connection configurations for package units supply and return air ducts?
Over/under and side by side
Nominal-sized tubing
False
It also rises

10. What kind of copper tubing is used for plumbing and heating applications?
The takeoff fitting
Any amount
Any amount
Nominal-sized tubing

11. What are the four materials used to make duct?
Static pressure - velocity pressure - and total pressure
With 4' saddles
Sheet metal - galvanized sheet metal - fiberglass - and flexduct
True

12. What are the components of a hard-start kit?
Outside of the male fitting
Infiltration and ventilation
Potential relay and start capacitor
12000

13. How are the condenser coils different on a high-efficiency unit?
SEER includes the energy used in the start-up and shut-down cycles
Inside diameter (ID)
They are larger
Inches of water column (in. WC)

14. In what state is the refrigerant in the compressor?
Vapor
The suction line or the low-pressure side
45 degrees F
12000

15. 9' round duct has a ballpark cfm of what?
Inclined manometer
300
75 degrees F dry bulb indoor - 95 degrees F drybulb outdoor - and 50% relative humidity
It will have a decrease in superheat

16. How many amps can 12 g wire handle?
When it is above a conditioned space
40 A
Vapor
20 A

17. Where do you check the amps on a motor?
Duct with insulation on the inside
1/4'
18 gauge
On the common terminal

18. What percentage silver do you need to use for an are-410 system?
15% silphos
Btu/hr (output) / wattage (input)
Infiltration and ventilation
The takeoff fitting

19. How will too much refrigerant effect subcooling?
30-35 degrees above ambient
It will be high
The takeoff fitting
8-12 degrees F

20. What kind of metering device do high-efficiency units usually use?
TXV
40 A
15% silphos
When it is a pull-through evaporator

21. What is the normal evaporator temperature?
A dirty evaporator
When the system is under pressure
45 degrees F
A diffuser

22. How will an overcharge affect an air-conditioning system with a fixed-orifice type metering device?
Dehydrated with caps on each end
2
20 A
It will have a decrease in superheat

23. How much superheat do you need to prevent liquid refrigerant from entering the compressor?
Inclined manometer
Pistons
Before the vent
Any amount

24. How will too much refrigerant effect subcooling?
It will be high
Duct with insulation on the inside
20 degrees F
15% silphos

25. If the rpm's are 1750 - how many poles does the motor have?
Rise
Positive
4
Positive

26. What do you use to check for leaks?
Heat load
Negative
Nitrogen with a small amount of refrigerant
25-ft or 50-ft

27. How many amps can 10 g wire handle?
By increasing the surface of the condenser coil
30 A
15 A
Pull a vacuum

28. At what temperature will soft solder melt?
When it is above a conditioned space
Below 800 degrees F
20 degrees F
Inside diameter (ID)

29. What type of air conditioning system must be charged using the superheat method?
Below 800 degrees F
A piston type metering device
In parallel
Nominal-sized tubing

30. Where do you apply flux when soldering?
A diffuser
150
ACR (air-conditioning refrigeration) tubing
Outside of the male fitting

31. At what temperature does refrigerant condense in a standard-efficiency unit?
300
95 degrees F outside - 80 degrees F inside - and 50% relative humidity
Standard
30-35 degrees above ambient

32. What are the two basic duct connection configurations for package units supply and return air ducts?
Over/under and side by side
Positive
105 degrees F
Negative

33. What are normal conditions - as defined by the ARI.
Yes
95 degrees F outside - 80 degrees F inside - and 50% relative humidity
Potential relay and start capacitor
20 degrees above ambient

34. The fan switch closes at what temperature?
140 degrees F
100 psig
400
To keep refrigerant from absorbing heat and to prevent condensation from forming on the line

35. When must a copper joint never be soldered or brazed?
Heat loss
Pi x radius squared
Boil the liquid refrigerant out ot the oil within the crankcase
When the system is under pressure

36. Where is insulation used on copper tubing used for air-conditioning?
The suction line or the low-pressure side
By increasing the surface of the condenser coil
False
Pull a vacuum

37. 13 SEER is classified as what kind of efficiency?
Static pressure - velocity pressure - and total pressure
High
Potential relay and start capacitor
300

38. Which type of wire can handle a higher ampacity?
Stranded
Potential relay and start capacitor
With a minimum of three evenly spaced self-tapping screws
It rises

39. What are the two types of blower drives?
S-clips and drives (cleats)
A dirty evaporator
Belt drive and direct drive
Outside diameter (OD)

40. If the rpm's are 1750 - how many poles does the motor have?
20 A
With an are rating
140 degrees F
4

41. What kind of copper tubing is used for refrigeration or air-conditioning applications?
An air-conditioning system that has all four components (compressor - condenser - metering device - and evaporator) in one housing.
Pi x radius squared
ACR (air-conditioning refrigeration) tubing
Outside diameter (OD)

42. Where is insulation used on copper tubing used for air-conditioning?
The suction line or the low-pressure side
5 degrees
RLA/FLA x 5
They are physically larger

43. What can cause a decrease in suction pressure on an air-conditioning system?
A band 4 inches or more in width
With an are rating
A dirty evaporator
Nominal-sized tubing

44. 7' round duct has a ballpark cfm of what?
An air-conditioning system that has all four components (compressor - condenser - metering device - and evaporator) in one housing.
Yes
In series
150

45. How many BTU's per ton?
S-clips and drives (cleats)
300
12000
Outside of the male fitting

46. The refrigerant within the evaporator will typically boil at what temperature when it is 75 degrees inside with a relative humidity of 50%?
A piston type metering device
40 degrees F
It will have a decrease in superheat
30 A

47. Square sheet metal duct is normally fabricated in a sheet metal shop and assembled in the field. (True or False)
True
2
Side-by-side and over-and-under
When the system is under pressure

48. Most duct insulation is made of what?
Dehydrated with caps on each end
Outside of the male fitting
Fiberglass
18 gauge

49. How many cfm per ton?
75 degrees F dry bulb indoor - 95 degrees F drybulb outdoor - and 50% relative humidity
400
30-35 degrees above ambient
To keep refrigerant from absorbing heat and to prevent condensation from forming on the line

50. What is the difference between SEER and EER?
400
SEER includes the energy used in the start-up and shut-down cycles
Yes
RLA/FLA x 5