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. What are the four materials used to make duct?
In parallel
Sheet metal - galvanized sheet metal - fiberglass - and flexduct
40 degrees F
They are physically larger

2. If the suction pressure rises - what happens to the head pressure?
It also rises
TXV
RLA/FLA x 5
Positive

3. Do you need a vent on a pull-through evaporator?
Rise
Sheet metal - galvanized sheet metal - fiberglass - and flexduct
Yes
S-clips and drives (cleats)

4. Square sheet metal duct is normally fabricated in a sheet metal shop and assembled in the field. (True or False)
Before the vent
Slugging
45-55%
True

5. If pressure rises - what happens to the superheat?
Average feet per minute X area in square feet (H' x W'/144)
Staples and tape
It rises
No

6. How do you calculate the area of a circle?
Pi x radius squared
2
Btu/hr (output) / wattage (input)
Inches of water column (in. WC)

7. Most duct insulation is made of what?
It also rises
Slugging
Fiberglass
Below 800 degrees F

8. Where do you apply flux when soldering?
12000
Outside of the male fitting
15 A
S-clips and drives (cleats)

9. The crankcase heater on an air-conditioning compressor is used to what?
ACR (air-conditioning refrigeration) tubing
Boil the liquid refrigerant out ot the oil within the crankcase
2 minutes
Infiltration and ventilation

10. What percentage silver do you need to use for an are-410 system?
Over 800 degrees F
Before the vent
20 degrees above ambient
15% silphos

11. How are high-efficiency condenser coils different from standard-efficiency condenser coils?
Over/under and side by side
Static pressure - velocity pressure - and total pressure
Fiberglass
They are physically larger

12. The fan switch opens at what temperature?
105 degrees F
Individual return air systems and central return air systems
Rise
Pi x radius squared

13. At what temperature does refrigerant condense in a high-efficiency unit?
Heat loss
Stranded
20 degrees above ambient
It will be low

14. How many BTU's per ton?
It rises
12000
To remove humidity and lower dry bulb temperature
Sheet metal - galvanized sheet metal - fiberglass - and flexduct

15. What is the range for normal superheat and subcooling?
8-12 degrees F
Nitrogen with a small amount of refrigerant
Yes
Duct - electrical - and mechanical

16. The evaporator is designed to remove what two types of heat?
Latent and sensible
Dehydrated with caps on each end
A dirty evaporator
Slugging

17. Do you need a vent on a pull-through evaporator?
Yes
Heat loss
100 psig
Common

18. Superheat should never be below how many degrees
Shorted winding - open winding - and grounded winding
An air-conditioning system that has all four components (compressor - condenser - metering device - and evaporator) in one housing.
Subtract ambient temperature from 100
5 degrees

19. What are the two functions of the air-conditioning system?
Duct - electrical - and mechanical
95 degrees F outside - 80 degrees F inside - and 50% relative humidity
To remove humidity and lower dry bulb temperature
Inches of water column (in. WC)

20. When must a copper joint never be soldered or brazed?
When the system is under pressure
By increasing the surface of the condenser coil
40 degrees F
Infiltration and ventilation

21. What distributes supply air to a room in a structure?
ACR (air-conditioning refrigeration) tubing
A diffuser
Inside diameter (ID)
400

22. When do you install an auxillary drain pan?
When it is above a conditioned space
Duct - electrical - and mechanical
400
The suction line or the low-pressure side

23. How many amps can 14 g wire handle?
On the common terminal
Slugging
15 A
TXV

24. What is considered normal operating conditions?
Inches of water column (in. WC)
It rises
75 degrees F dry bulb indoor - 95 degrees F drybulb outdoor - and 50% relative humidity
By increasing the surface of the condenser coil

25. Where do you check the amps on a motor?
By increasing the surface of the condenser coil
TXV
300
On the common terminal

26. Where is insulation used on copper tubing used for air-conditioning?
Pull a vacuum
Duct - electrical - and mechanical
The suction line or the low-pressure side
Yes

27. How is insulation around a duct rated?
Compressor
40 A
With an are rating
It will have a decrease in superheat

28. In what length rolls is soft copper tubing normally available?
Potential relay and start capacitor
25-ft or 50-ft
Fiberglass
Outside diameter (OD)

29. What is a package unit?
75 degrees F dry bulb indoor - 95 degrees F drybulb outdoor - and 50% relative humidity
Outside diameter (OD)
An air-conditioning system that has all four components (compressor - condenser - metering device - and evaporator) in one housing.
Positive

30. How many amps can 8 g wire handle?
40 A
1/4'
The suction line or the low-pressure side
ACR (air-conditioning refrigeration) tubing

31. How is the high pressure switch wired with the low pressure switch?
In parallel
To remove humidity and lower dry bulb temperature
The takeoff fitting
15 A

32. What gauge is thermostat wire?
Outside diameter (OD)
Dehydrated with caps on each end
18 gauge
A diffuser

33. What are the two ways that fresh air enters a structure?
Infiltration and ventilation
8-12 degrees F
400
Staples and tape

34. 7' round duct has a ballpark cfm of what?
25-ft or 50-ft
With 4' saddles
150
S-clips and drives (cleats)

35. What are the three crafts normally associated with an air-conditioned installation?
40 degrees F
200
40 A
Duct - electrical - and mechanical

36. 10' round duct has a ballpark cfm of what?
It rises
400
150
Before the vent

37. What do you use to connect square and rectangular ductboard together?
Standard
Pistons
S-clips and drives (cleats)
Nominal-sized tubing

38. What are the three ways a motor can fail electrically?
Individual return air systems and central return air systems
Potential relay and start capacitor
Shorted winding - open winding - and grounded winding
200

39. What do you do after you braze a system?
RLA/FLA x 5
Pull a vacuum
Btu/hr (output) / wattage (input)
20 degrees above ambient

40. A reciprocating compressor has what sort of moving parts?
75 degrees F dry bulb indoor - 95 degrees F drybulb outdoor - and 50% relative humidity
Pistons
Outside of the male fitting
The suction line or the low-pressure side

41. 10 SEER is classified as what kind of efficiency?
S-clips and drives (cleats)
25-ft or 50-ft
Standard
20 degrees F

42. If the rpm's are 1050 - how many poles does the motor have?
No
6
Dehydrated with caps on each end
To remove humidity and lower dry bulb temperature

43. How is the high pressure switch wired with the low pressure switch?
In parallel
40 A
To keep refrigerant from absorbing heat and to prevent condensation from forming on the line
A diffuser

44. Will a dirty condenser cause a rise or fall in pressure?
Sheet metal - galvanized sheet metal - fiberglass - and flexduct
Rise
30 degrees F
Nominal-sized tubing

45. How are round ducts connected to one another?
105 degrees F
With a minimum of three evenly spaced self-tapping screws
When the system is under pressure
TXV

46. What are the two types of blower drives?
6
Dehydrated with caps on each end
It also rises
Belt drive and direct drive

47. What are the four materials used to make duct?
Below 800 degrees F
Sheet metal - galvanized sheet metal - fiberglass - and flexduct
With a minimum of three evenly spaced self-tapping screws
30 A

48. If the rpm's are 1750 - how many poles does the motor have?
Inches of water column (in. WC)
4
Indoor fan motor - outdoor fan motor - and the compressor
20 degrees above ambient

49. How is ACR tubing sized?
Staples and tape
Outside diameter (OD)
Side-by-side and over-and-under
Nominal-sized tubing

50. How much superheat do you need to prevent liquid refrigerant from entering the compressor?
S-clips and drives (cleats)
Yes
30 A
Any amount