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 many cfm per ton?
300
The takeoff fitting
On the common terminal
400

2. The A/C size is calculated by what?
Heat load
Negative
Below 800 degrees F
TXV

3. At what temperature will brazing melt?
When it is above a conditioned space
15% silphos
A diffuser
Over 800 degrees F

4. Can refrigerant line sets be altered in length?
A diffuser
5 degrees
Yes
With 4' saddles

5. Where do you install a trap on a drain line?
6
No
15% silphos
Before the vent

6. What gauge is thermostat wire?
18 gauge
In series
Before the vent
Rise

7. How will too much refrigerant effect superheat?
ACR (air-conditioning refrigeration) tubing
It will be low
95 degrees F outside - 80 degrees F inside - and 50% relative humidity
Stranded

8. A reciprocating compressor has what sort of moving parts?
40 degrees F
Heat loss
The takeoff fitting
Pistons

9. How are round ducts connected to one another?
High
Outside of the male fitting
2 minutes
With a minimum of three evenly spaced self-tapping screws

10. 7' round duct has a ballpark cfm of what?
40 A
Nominal-sized tubing
Dehydrated with caps on each end
150

11. What is considered normal operating conditions?
To lower the amount of pressure drop through the coil
105 degrees F
Over 800 degrees F
75 degrees F dry bulb indoor - 95 degrees F drybulb outdoor - and 50% relative humidity

12. How do you achieve high-efficiency?
45-55%
By increasing the surface of the condenser coil
40 A
15% silphos

13. If the suction pressure rises - what happens to the head pressure?
It also rises
Dehydrated with caps on each end
1/4'
Nominal-sized tubing

14. What is lined duct?
Common
Duct with insulation on the inside
40 degrees F
The suction line or the low-pressure side

15. Sections of duct board can be fastened together with what?
To lower the amount of pressure drop through the coil
When the system is under pressure
Shorted winding - open winding - and grounded winding
Staples and tape

16. Multiple-zone systems often use what to alleviate the problem of excess air when only some zones are calling for conditioning?
True
A diffuser
A bypass duct or a dump zone
95 degrees F outside - 80 degrees F inside - and 50% relative humidity

17. At what temperature does refrigerant condense in a standard-efficiency unit?
It will have a decrease in superheat
40 degrees F
30-35 degrees above ambient
To remove humidity and lower dry bulb temperature

18. What kind of copper tubing is used for refrigeration or air-conditioning applications?
Heat load
It will be low
ACR (air-conditioning refrigeration) tubing
Slugging

19. What are the two basic duct connection configurations for package units supply and return air ducts?
40 A
Before the vent
Over/under and side by side
Duct with insulation on the inside

20. At what temperature does refrigerant condense in a standard-efficiency unit?
30-35 degrees above ambient
40 A
Static pressure - velocity pressure - and total pressure
45 degrees F

21. How are the condenser coils different on a high-efficiency unit?
Individual return air systems and central return air systems
They are larger
Pistons
An air-conditioning system that has all four components (compressor - condenser - metering device - and evaporator) in one housing.

22. On what terminal do you check amperage?
TXV
Below 800 degrees F
Latent and sensible
Common

23. What kind of refrigeratnts must be added in liquid form?
Blended refrigerants
6
Average feet per minute X area in square feet (H' x W'/144)
100 psig

24. What is the design boiling point for most evaporator coils in residential air conditioning?
30 degrees F
40 degrees F
Yes
To keep refrigerant from absorbing heat and to prevent condensation from forming on the line

25. What is lined duct?
Duct with insulation on the inside
False
A piston type metering device
A piston type metering device

26. Why are some ACR tubing lines insulated?
Vapor
Side-by-side and over-and-under
Boil the liquid refrigerant out ot the oil within the crankcase
To keep refrigerant from absorbing heat and to prevent condensation from forming on the line

27. The furnace size is calculated by what?
100 psig
Heat loss
200
It will have a decrease in superheat

28. What kind of metering device do high-efficiency units usually use?
TXV
150
Infiltration and ventilation
A bypass duct or a dump zone

29. How many amps can 12 g wire handle?
30 degrees F
With a minimum of three evenly spaced self-tapping screws
Common
20 A

30. What are the three major power-consuming devices on an air-conditioning system?
400
Indoor fan motor - outdoor fan motor - and the compressor
With an are rating
30 A

31. At what temperature does refrigerant condense in a high-efficiency unit?
A swaging tool
20 degrees above ambient
An air-conditioning system that has all four components (compressor - condenser - metering device - and evaporator) in one housing.
Over 800 degrees F

32. What are the three crafts normally associated with an air-conditioned installation?
Duct - electrical - and mechanical
150
SEER includes the energy used in the start-up and shut-down cycles
To keep refrigerant from absorbing heat and to prevent condensation from forming on the line

33. 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
Fiberglass
Rise
ACR (air-conditioning refrigeration) tubing

34. What is the name of the fitting where the branch line leaves the duct?
150
40 A
The takeoff fitting
5 degrees

35. Most duct insulation is made of what?
It will have a decrease in superheat
400
Staples and tape
Fiberglass

36. What gauge is thermostat wire?
Indoor fan motor - outdoor fan motor - and the compressor
30 A
20 degrees above ambient
18 gauge

37. 10 SEER is classified as what kind of efficiency?
A band 4 inches or more in width
Standard
150
2

38. Pressure in ductwork is measured In what?
Boil the liquid refrigerant out ot the oil within the crankcase
Inches of water column (in. WC)
When the system is under pressure
Stranded

39. How are the condenser coils different on a high-efficiency unit?
Slugging
A bypass duct or a dump zone
45 degrees F
They are larger

40. 10' round duct has a ballpark cfm of what?
A swaging tool
400
Shorted winding - open winding - and grounded winding
Individual return air systems and central return air systems

41. Which is more efficient - a TXV or a fixed-orifice metering device?
TXV
18 gauge
100
It will have a decrease in superheat

42. The evaporator is designed to remove what two types of heat?
20 degrees F
Latent and sensible
A dirty evaporator
Btu/hr (output) / wattage (input)

43. Why is it necessary to have multiple refrigerant circuits in some evaporator coils?
Individual return air systems and central return air systems
To lower the amount of pressure drop through the coil
Yes
Infiltration and ventilation

44. What kind of copper tubing is used for plumbing and heating applications?
150
Nominal-sized tubing
It will have a decrease in superheat
30-35 degrees above ambient

45. How is the high pressure switch wired with the low pressure switch?
1/4'
Duct - electrical - and mechanical
In parallel
105 degrees F

46. Where do you check the amps on a motor?
150
It also rises
100 psig
On the common terminal

47. The fan switch closes at what temperature?
Heat loss
Btu/hr (output) / wattage (input)
When the system is under pressure
140 degrees F

48. How do you calculate the area of a circle?
False
75 degrees F dry bulb indoor - 95 degrees F drybulb outdoor - and 50% relative humidity
S-clips and drives (cleats)
Pi x radius squared

49. What kind of copper tubing is used for refrigeration or air-conditioning applications?
On the common terminal
High
ACR (air-conditioning refrigeration) tubing
Positive

50. How does ACR copper pipe come?
Btu/hr (output) / wattage (input)
By increasing the surface of the condenser coil
Dehydrated with caps on each end
Positive