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. When do you install an auxillary drain pan?
Below 800 degrees F
Pull a vacuum
When it is above a conditioned space
With a minimum of three evenly spaced self-tapping screws

2. At what temperature will soft solder melt?
Below 800 degrees F
30 degrees F
The takeoff fitting
18 gauge

3. What is the typical temperature difference between a standard-efficiency condenser and the ambient temperature?
40 A
30 degrees F
On the common terminal
Potential relay and start capacitor

4. What are the two basic duct connection configurations for package units supply and return air ducts?
When the system is under pressure
L-type
Over/under and side by side
Pistons

5. Most duct insulation is made of what?
Latent and sensible
Fiberglass
With 4' saddles
140 degrees F

6. What is it called when liquid refrigerant gets into the compressor?
Pistons
Yes
Vapor
Slugging

7. Do you need a trap on a pull-through evaporator?
Shorted winding - open winding - and grounded winding
Yes
8
Negative

8. How many BTU's per ton?
Btu/hr (output) / wattage (input)
12000
High
Any amount

9. What sort of pressure will a push-through evaporator have?
300
Positive
Before the vent
Blended refrigerants

10. When do you install an auxillary drain pan?
A dirty evaporator
The suction line or the low-pressure side
When it is above a conditioned space
Staples and tape

11. What do you use to check for leaks?
Inches of water column (in. WC)
In series
Latent and sensible
Nitrogen with a small amount of refrigerant

12. What is the range for normal superheat and subcooling?
Nominal-sized tubing
Dehydrated with caps on each end
8-12 degrees F
A band 4 inches or more in width

13. Superheat should never be below how many degrees
5 degrees
It rises
100
Potential relay and start capacitor

14. How many amps can 14 g wire handle?
Boil the liquid refrigerant out ot the oil within the crankcase
Blended refrigerants
Yes
15 A

15. The evaporator is designed to remove what two types of heat?
Inches of water column (in. WC)
Latent and sensible
Below 800 degrees F
An air-conditioning system that has all four components (compressor - condenser - metering device - and evaporator) in one housing.

16. At what temperature will soft solder melt?
No
Static pressure - velocity pressure - and total pressure
Below 800 degrees F
95 degrees F outside - 80 degrees F inside - and 50% relative humidity

17. Multiple-zone systems often use what to alleviate the problem of excess air when only some zones are calling for conditioning?
A bypass duct or a dump zone
150
TXV
Over 800 degrees F

18. 10' round duct has a ballpark cfm of what?
400
S-clips and drives (cleats)
45-55%
Outside of the male fitting

19. What do you use to check for leaks?
Nitrogen with a small amount of refrigerant
S-clips and drives (cleats)
20 A
SEER includes the energy used in the start-up and shut-down cycles

20. The refrigerant within the evaporator will typically boil at what temperature when it is 75 degrees inside with a relative humidity of 50%?
Over 800 degrees F
40 degrees F
Shorted winding - open winding - and grounded winding
TXV

21. How is ACR tubing sized?
Outside diameter (OD)
150
Infiltration and ventilation
20 degrees F

22. The furnace size is calculated by what?
Outside of the male fitting
L-type
2
Heat loss

23. What are the two functions of the air-conditioning system?
45-55%
To remove humidity and lower dry bulb temperature
Shorted winding - open winding - and grounded winding
8

24. How many amps can 10 g wire handle?
4
40 degrees F
30 A
Before the vent

25. Do you need a trap on a push-through evaporator?
15% silphos
With a minimum of three evenly spaced self-tapping screws
No
Inside diameter (ID)

26. At what temperature does refrigerant condense in a high-efficiency unit?
A dirty evaporator
20 degrees above ambient
Average feet per minute X area in square feet (H' x W'/144)
By increasing the surface of the condenser coil

27. Where do you install a trap on a drain line?
With a minimum of three evenly spaced self-tapping screws
Nitrogen with a small amount of refrigerant
Before the vent
Compressor

28. What gauge is thermostat wire?
Indoor fan motor - outdoor fan motor - and the compressor
18 gauge
100
12000

29. On what terminal do you check amperage?
Common
30 A
A diffuser
300

30. The crankcase heater on an air-conditioning compressor is used to what?
15 A
140 degrees F
Inches of water column (in. WC)
Boil the liquid refrigerant out ot the oil within the crankcase

31. The fan switch opens at what temperature?
RLA/FLA x 5
105 degrees F
Shorted winding - open winding - and grounded winding
With 4' saddles

32. The A/C size is calculated by what?
5 degrees
Boil the liquid refrigerant out ot the oil within the crankcase
A diffuser
Heat load

33. How many cfm per ton?
Positive
No
20 degrees above ambient
400

34. How are the condenser coils different on a high-efficiency unit?
S-clips and drives (cleats)
15% silphos
Compressor
They are larger

35. Sections of duct board can be fastened together with what?
40 A
Static pressure - velocity pressure - and total pressure
Subtract ambient temperature from 100
Staples and tape

36. What are the two basic duct connection configurations for package units supply and return air ducts?
Side-by-side and over-and-under
Over/under and side by side
12000
Rise

37. If the suction pressure rises - what happens to the head pressure?
45-55%
Potential relay and start capacitor
It also rises
True

38. What are the two types of return air systems in residential installations?
Individual return air systems and central return air systems
Infiltration and ventilation
TXV
Nitrogen with a small amount of refrigerant

39. The fan switch closes at what temperature?
140 degrees F
Latent and sensible
8-12 degrees F
When it is above a conditioned space

40. What are the four materials used to make duct?
Fiberglass
Inches of water column (in. WC)
Nitrogen with a small amount of refrigerant
Sheet metal - galvanized sheet metal - fiberglass - and flexduct

41. 7' round duct has a ballpark cfm of what?
Duct - electrical - and mechanical
Boil the liquid refrigerant out ot the oil within the crankcase
On the common terminal
150

42. What component changes refrigerant from a low pressure gas to a high pressure gas?
Sheet metal - galvanized sheet metal - fiberglass - and flexduct
Potential relay and start capacitor
30 degrees F
Compressor

43. 8' round duct has a ballpark cfm of what?
With an are rating
Negative
A band 4 inches or more in width
200

44. What are the two types of blower drives?
15 A
Compressor
400
Belt drive and direct drive

45. How many amps can 10 g wire handle?
Dehydrated with caps on each end
When it is a pull-through evaporator
30 A
25-ft or 50-ft

46. What percentage silver do you need to use for an are-410 system?
When it is above a conditioned space
15% silphos
18 gauge
Slugging

47. 10 SEER is classified as what kind of efficiency?
Standard
True
Outside of the male fitting
Outside of the male fitting

48. How will too much refrigerant effect superheat?
When the system is under pressure
Average feet per minute X area in square feet (H' x W'/144)
4
It will be low

49. What are the three pressures created by moving air in ductwork?
Btu/hr (output) / wattage (input)
High
Static pressure - velocity pressure - and total pressure
ACR (air-conditioning refrigeration) tubing

50. What are the three crafts normally associated with an air-conditioned installation?
Yes
Over 800 degrees F
Duct - electrical - and mechanical
With an are rating