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. In what state is the refrigerant in the compressor?
Side-by-side and over-and-under
200
Vapor
The suction line or the low-pressure side

2. Do you need a trap on a pull-through evaporator?
Yes
2 minutes
True
A band 4 inches or more in width

3. Where do you check the amps on a motor?
150
It will be low
On the common terminal
Individual return air systems and central return air systems

4. How are high-efficiency condenser coils different from standard-efficiency condenser coils?
Btu/hr (output) / wattage (input)
A bypass duct or a dump zone
With a minimum of three evenly spaced self-tapping screws
They are physically larger

5. What type of air conditioning system must be charged using the superheat method?
Slugging
40 A
A piston type metering device
TXV

6. What is the typical pressure differance across a TXV?
Yes
A swaging tool
Side-by-side and over-and-under
100 psig

7. At what temperature will brazing melt?
ACR (air-conditioning refrigeration) tubing
Before the vent
Over 800 degrees F
Belt drive and direct drive

8. If the rpm's are 750 - how many poles does the motor have?
8
It also rises
Yes
Nitrogen with a small amount of refrigerant

9. What is the typical temperature difference between a high-efficiency condenser and the ambient temperature?
40 degrees F
Duct with insulation on the inside
100 psig
20 degrees F

10. The refrigerant within the evaporator will typically boil at what temperature when it is 75 degrees inside with a relative humidity of 50%?
A bypass duct or a dump zone
40 degrees F
To lower the amount of pressure drop through the coil
Heat loss

11. What are normal conditions - as defined by the ARI.
12000
TXV
95 degrees F outside - 80 degrees F inside - and 50% relative humidity
Indoor fan motor - outdoor fan motor - and the compressor

12. The load on the evaporater will effect which pressure?
4
Suction
With 4' saddles
300

13. What distributes supply air to a room in a structure?
A diffuser
Any amount
12000
6

14. What are the two basic duct connection configurations for package units supply and return air ducts?
20 degrees F
Over/under and side by side
8
5 degrees

15. 6' round duct has a ballpark cfm of what?
40 A
False
100
Duct - electrical - and mechanical

16. What do you use to check for leaks?
Potential relay and start capacitor
Slugging
Nitrogen with a small amount of refrigerant
Dehydrated with caps on each end

17. What sort of pressure will a push-through evaporator have?
Positive
Btu/hr (output) / wattage (input)
Boil the liquid refrigerant out ot the oil within the crankcase
Heat loss

18. Sections of duct board can be fastened together with what?
Below 800 degrees F
Average feet per minute X area in square feet (H' x W'/144)
Staples and tape
Fiberglass

19. How will too much refrigerant effect superheat?
In series
It will be low
Below 800 degrees F
Subtract ambient temperature from 100

20. Which is more efficient - a TXV or a fixed-orifice metering device?
Subtract ambient temperature from 100
TXV
With an are rating
Slugging

21. How do you calculate ballpark superheat?
Subtract ambient temperature from 100
Yes
40 degrees F
Sheet metal - galvanized sheet metal - fiberglass - and flexduct

22. Most duct insulation is made of what?
75 degrees F dry bulb indoor - 95 degrees F drybulb outdoor - and 50% relative humidity
It will have a decrease in superheat
Fiberglass
400

23. What is it called when liquid refrigerant gets into the compressor?
Rise
Slugging
With a minimum of three evenly spaced self-tapping screws
Stranded

24. What is used to measure static air pressure in ducts.
It also rises
It will be low
Yes
Inclined manometer

25. How do you calculate LRA?
15% silphos
1/4'
RLA/FLA x 5
No

26. What kind of metering device do high-efficiency units usually use?
200
TXV
Inclined manometer
True

27. At what temperature will brazing melt?
Compressor
Over 800 degrees F
400
8

28. Why is it necessary to have multiple refrigerant circuits in some evaporator coils?
To lower the amount of pressure drop through the coil
200
Yes
Duct - electrical - and mechanical

29. How is insulation around a duct rated?
RLA/FLA x 5
False
With an are rating
Compressor

30. 8' round duct has a ballpark cfm of what?
Dehydrated with caps on each end
To keep refrigerant from absorbing heat and to prevent condensation from forming on the line
40 degrees F
200

31. Superheat should never be below how many degrees
True
Sheet metal - galvanized sheet metal - fiberglass - and flexduct
18 gauge
5 degrees

32. 6' round duct has a ballpark cfm of what?
Yes
2 minutes
100
20 A

33. How will too much refrigerant effect superheat?
30 A
On the common terminal
It will be low
When it is above a conditioned space

34. What are the three pressures created by moving air in ductwork?
Yes
Boil the liquid refrigerant out ot the oil within the crankcase
Static pressure - velocity pressure - and total pressure
Belt drive and direct drive

35. The fan switch opens at what temperature?
105 degrees F
Pi x radius squared
By increasing the surface of the condenser coil
40 degrees F

36. How are the condenser coils different on a high-efficiency unit?
It will be low
They are larger
1/4'
By increasing the surface of the condenser coil

37. Does a package unit come from the factory pre-charged?
Yes
No
Heat loss
Average feet per minute X area in square feet (H' x W'/144)

38. What is the typical temperature difference between a standard-efficiency condenser and the ambient temperature?
By increasing the surface of the condenser coil
It will be high
400
30 degrees F

39. What are the two types of blower drives?
Belt drive and direct drive
Yes
S-clips and drives (cleats)
2 minutes

40. How is flexible duct supported?
A band 4 inches or more in width
Yes
ACR (air-conditioning refrigeration) tubing
Compressor

41. What are the two ways that fresh air enters a structure?
The suction line or the low-pressure side
8
Infiltration and ventilation
Rise

42. When do you install an auxillary drain pan?
18 gauge
20 A
It will be low
When it is above a conditioned space

43. The fan switch closes at what temperature?
Yes
A swaging tool
140 degrees F
Rise

44. How will too much refrigerant effect subcooling?
Static pressure - velocity pressure - and total pressure
A band 4 inches or more in width
Inside diameter (ID)
It will be high

45. What is used to measure static air pressure in ducts.
100
Inclined manometer
30-35 degrees above ambient
To remove humidity and lower dry bulb temperature

46. How do you calculate cfm?

Warning: Invalid argument supplied for foreach() in /var/www/html/basicversity.com/show_quiz.php on line 183

47. How many cfm per ton?
20 degrees F
400
Rise
It will be low

48. What are the four materials used to make duct?
Sheet metal - galvanized sheet metal - fiberglass - and flexduct
Duct - electrical - and mechanical
Belt drive and direct drive
Infiltration and ventilation

49. What is considered normal operating conditions?
Yes
75 degrees F dry bulb indoor - 95 degrees F drybulb outdoor - and 50% relative humidity
With 4' saddles
300

50. Why are some ACR tubing lines insulated?
Compressor
Outside of the male fitting
Common
To keep refrigerant from absorbing heat and to prevent condensation from forming on the line