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 do you do after you braze a system?
100
With a minimum of three evenly spaced self-tapping screws
Latent and sensible
Pull a vacuum

2. If pressure rises - what happens to the superheat?
40 degrees F
20 degrees above ambient
Over 800 degrees F
It rises

3. What sort of pressure will a pull-through evaporator have?
Indoor fan motor - outdoor fan motor - and the compressor
TXV
Heat load
Negative

4. How much superheat do you need to prevent liquid refrigerant from entering the compressor?
Duct - electrical - and mechanical
Any amount
In parallel
30 A

5. What sort of pressure will a pull-through evaporator have?
Belt drive and direct drive
18 gauge
Negative
Indoor fan motor - outdoor fan motor - and the compressor

6. If the rpm's are 3450 - how many poles does the motor have?
Standard
On the common terminal
TXV
2

7. What are the three ways a motor can fail electrically?
Shorted winding - open winding - and grounded winding
When the system is under pressure
Btu/hr (output) / wattage (input)
100 psig

8. How many amps can 12 g wire handle?
Over/under and side by side
400
15% silphos
20 A

9. The compressor is cooled by liquid refrigerant. (True of False)
When it is above a conditioned space
6
False
8

10. When do you install an auxillary drain pan?
When it is above a conditioned space
To keep refrigerant from absorbing heat and to prevent condensation from forming on the line
100 psig
False

11. How is the high pressure switch wired with the low pressure switch?
30-35 degrees above ambient
They are larger
200
In parallel

12. If the rpm's are 3450 - how many poles does the motor have?
2
By increasing the surface of the condenser coil
4
45 degrees F

13. How will an overcharge affect an air-conditioning system with a fixed-orifice type metering device?
2
Potential relay and start capacitor
An air-conditioning system that has all four components (compressor - condenser - metering device - and evaporator) in one housing.
It will have a decrease in superheat

14. 8' round duct has a ballpark cfm of what?
Subtract ambient temperature from 100
Inches of water column (in. WC)
Stranded
200

15. Superheat should never be below how many degrees
Suction
Inside diameter (ID)
5 degrees
12000

16. What are the four materials used to make duct?
Average feet per minute X area in square feet (H' x W'/144)
High
100
Sheet metal - galvanized sheet metal - fiberglass - and flexduct

17. What is the design boiling point for most evaporator coils in residential air conditioning?
40 degrees F
Over 800 degrees F
200
400

18. How will an overcharge affect an air-conditioning system with a fixed-orifice type metering device?
1/4'
Heat load
1/4'
It will have a decrease in superheat

19. Where do you apply flux when soldering?
Nitrogen with a small amount of refrigerant
S-clips and drives (cleats)
Outside of the male fitting
Sheet metal - galvanized sheet metal - fiberglass - and flexduct

20. How are round ducts connected to one another?
Any amount
45 degrees F
With a minimum of three evenly spaced self-tapping screws
200

21. What are the two types of package units?
When it is a pull-through evaporator
Side-by-side and over-and-under
40 degrees F
15% silphos

22. If the rpm's are 750 - how many poles does the motor have?
Fiberglass
8
Individual return air systems and central return air systems
Shorted winding - open winding - and grounded winding

23. The load on the evaporater will effect which pressure?
20 A
30 degrees F
TXV
Suction

24. Where do you apply flux when soldering?
With 4' saddles
Outside of the male fitting
S-clips and drives (cleats)
Infiltration and ventilation

25. Sections of duct board can be fastened together with what?
Staples and tape
Common
25-ft or 50-ft
When the system is under pressure

26. What is the name of the fitting where the branch line leaves the duct?
Dehydrated with caps on each end
Pi x radius squared
The takeoff fitting
Yes

27. Which type of wire can handle a higher ampacity?
5 degrees
Dehydrated with caps on each end
Stranded
Outside of the male fitting

28. What gauge is thermostat wire?
18 gauge
Yes
To remove humidity and lower dry bulb temperature
2 minutes

29. How many BTU's per ton?
100
SEER includes the energy used in the start-up and shut-down cycles
The suction line or the low-pressure side
12000

30. 7' round duct has a ballpark cfm of what?
With a minimum of three evenly spaced self-tapping screws
30-35 degrees above ambient
Common
150

31. 13 SEER is classified as what kind of efficiency?
Indoor fan motor - outdoor fan motor - and the compressor
High
It will be low
With an are rating

32. The A/C size is calculated by what?
2 minutes
The takeoff fitting
Heat load
They are larger

33. How many BTU's per ton?
30 degrees F
6
12000
105 degrees F

34. How long should you leave a system off once you kill power before restarting it?
Suction
2 minutes
Pistons
6

35. Square sheet metal duct is normally fabricated in a sheet metal shop and assembled in the field. (True or False)
Latent and sensible
Compressor
True
By increasing the surface of the condenser coil

36. The A/C size is calculated by what?
Heat load
Nominal-sized tubing
40 degrees F
2 minutes

37. What is used to measure static air pressure in ducts.
100 psig
Inclined manometer
Heat load
Outside of the male fitting

38. What is the typical temperature difference between a high-efficiency condenser and the ambient temperature?
Standard
20 degrees F
When the system is under pressure
A swaging tool

39. What are the two types of blower drives?
A piston type metering device
It rises
Belt drive and direct drive
100 psig

40. 10' round duct has a ballpark cfm of what?
When it is above a conditioned space
30 degrees F
400
18 gauge

41. What is considered normal operating conditions?
Side-by-side and over-and-under
To remove humidity and lower dry bulb temperature
75 degrees F dry bulb indoor - 95 degrees F drybulb outdoor - and 50% relative humidity
Belt drive and direct drive

42. What is the typical temperature difference between a standard-efficiency condenser and the ambient temperature?
They are larger
True
30 degrees F
TXV

43. How do you calculate LRA?
Shorted winding - open winding - and grounded winding
RLA/FLA x 5
Infiltration and ventilation
On the common terminal

44. 8' round duct has a ballpark cfm of what?
200
Inclined manometer
In parallel
15 A

45. The evaporator is designed to remove what two types of heat?
A swaging tool
A swaging tool
In series
Latent and sensible

46. How many amps can 14 g wire handle?
2
400
Boil the liquid refrigerant out ot the oil within the crankcase
15 A

47. The furnace size is calculated by what?
Individual return air systems and central return air systems
SEER includes the energy used in the start-up and shut-down cycles
Heat loss
20 degrees above ambient

48. What is the typical pressure differance across a TXV?
100 psig
Yes
By increasing the surface of the condenser coil
A piston type metering device

49. What are normal conditions - as defined by the ARI.
Inches of water column (in. WC)
With an are rating
95 degrees F outside - 80 degrees F inside - and 50% relative humidity
30 degrees F

50. What are the three major power-consuming devices on an air-conditioning system?
Yes
Indoor fan motor - outdoor fan motor - and the compressor
Heat load
A swaging tool