Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
126 Cards in this Set
- Front
- Back
At what voltage reading should you get between R and C on a circuit board?
|
24V
|
|
Capacitors are checked in microfarads, what meter setting would you use to check a capacitor?
|
MFD |
|
What voltage would i expect to find on a air handler?
|
240V |
|
Name all the refrigerant types on your gauges
|
R-404A,R-22,R-410A |
|
On a multimeter, what does VDC stand for?
|
Volts DC |
|
Select the four system configurations?
|
Package unit,Horizontal or multi-poised, Down-flow,Up-flow
|
|
Select the items that count as proper attire when you arrive at each service call
|
Clean shaven or properly groomed facial hair, Proper shoes, Company shirt tucked in
|
|
Select the refrigerant type that is stored in the GREEN colored drum.
|
R-22
|
|
Select the refrigerant type that is stored in the ROSE colored drum.
|
R-410A |
|
The big refrigerant line temperature is 55 degrees and the refrigerant saturation temperature for R-22 is 40 degrees. What is the super-heat?
|
15 degrees
|
|
The blue gauge reads the refrigerant saturation temperature in which component?
|
Evaporator |
|
The high side gauge reads the refrigerant saturation temperature in which component?
|
Condensor |
|
The PSI on the red gauge is 140 degrees. What is the R-410 temperature ?
|
50 degrees
|
|
What am I: A device that automatically regulates temperature, or that activates a device when the temperature reaches a certain point:
|
T-stat |
|
What am I: A device that is used to enable rotational or linear movement, while reducing friction and handling stress:
|
Blower
|
|
What am I: formally defined to be the difference of electric potential between two points of a conductor carrying a constant current of one ampere, when the power dissipated between these points is equal to one watt:
|
Volt
|
|
What are the pressure scales on the blue gauge? Check all that apply
|
PSI,Inches of mercury
|
|
What color hose connects to the service valve of the big refrigerant line?
|
Blue |
|
What color is associated with R-410a on your gauges?
|
Rose |
|
What does AAC stand for?
|
Amps AC
|
|
What information can we gather from the data tag?
|
Type of refrigerant
|
|
What is the color of the drum used to recover refrigerant
|
Gray and Yellow
|
|
What is the pressure range for the high side gauge
|
0-800
|
|
What is the voltage reading you should get at the disconnect of a residential condensing unit?
|
240V |
|
What is the voltage reading you should get at the junction box of a furnace?
|
120V |
|
What is the yellow hose used for?
|
Performing a vacuum and recovering refrigerant
|
|
What voltage reading should you get between R and C on a circuit board?
|
24V |
|
When brazing copper , a tech should do what to the lines to protect line integrity?
|
purge the line with nitrogen
|
|
When charging a system with R-22 you should charge the system as:
|
Liquid, vapor, and tacos
|
|
When checking a refrigerant charge with a low super-heat which of the following could the cause?
|
Low refrigerant
|
|
Where in the refrigeration system is the heat absorbed into the refrigerant?
|
The evaporator
|
|
Where in the refrigeration system is the heat rejected from the refrigerant?
|
The condenser
|
|
Which gauge is the compound gauge?
|
The blue gauge
|
|
Which hose on your refrigerant gauges is connected to the recovery cylinder?
|
Yellow |
|
Which of the following can be checked or measured in voltage AC?
|
Power at the disconnect
|
|
Which of the following can NOT be measured in amperage?
|
Contactor
|
|
Which of the following instruments is usually a compound gauge:
|
The low side gauge on a set of refrigerant manifold gauges
|
|
Which of the following instruments is usually referred to as the high side gauge:
|
The red gauge
|
|
Which of the following is NOT a part of the condensing unit?
|
Heat exchanger
|
|
Which of the following is NOT considered a major component of the 4 system configurations?
|
Contactor
|
|
Which of the following would you check using continuity?
|
Technician suspects a motor has gone bad, Technician suspect wire integrity has been compromised
|
|
Which readings are needed to calculate super-heat?
|
The blue gauge and the big refrigerant line
|
|
Which refrigerant line is insulated ?
|
The suction line
|
|
Which refrigerants types are depicted on your gauges?
|
R-410 A, R-22
|
|
You should never fill your recovery tank more than __ to allow room for expansion
|
80% |
|
Your compound gauge reads a saturation temperature of 60 degrees for R-22. What is the corresponding PSI.
|
100 psi
|
|
Your red gauge read 270 PSI. What is the corresponding temperature for R-410a.
|
90 degrees
|
|
Which of the following is not considered a safety?
|
Gas Valve
|
|
Which of the following's only purpose is to protect the transformer?
|
Fuse
|
|
What should the gas pressure be on a furnace that uses propane?
|
10.5
|
|
True or False: A standing pilot furnace has an inducer motor.
|
False
|
|
What should the flue pipe pitch be for a condensing furnace?
|
1/4
|
|
What type of transformer has more turns in the primary winding than in the secondary winding?
|
Step-down Transformer
|
|
If you set the thermostat for a call for heat and nothing happens, what two wires would you check?
|
W AND C
|
|
What is the applied voltage for the gas valve?
|
24V |
|
Which setting on a multi-meter is used to check batteries?
|
VDC
|
|
What does the roll out switch do?
|
Locks furnace out in case of a flame roll out
|
|
What is the purpose of an 80% furnace inducer fan motor?
|
To remove flue gases from the furnace, To create a negative pressure
|
|
What type of circuit is the high limit and the rollout switches wired in?
|
Series
|
|
Which color wire is used for the reversing valve of a heat pump?
|
Orange
|
|
If you set the thermostat for a call for heat and nothing happens, what two wires would you check?
|
W and C
|
|
What are the terminals of a Thermostat?
|
R, W, G, Y, C, O
|
|
Which of the following is a characteristic of an 80% furnace?
|
Metal flue pipe
|
|
Which multi-meter setting is used to check the resistance of an igniter?
|
Ohms
|
|
Which setting on the thermostat will cause the blower to run continuously?
|
On
|
|
What gauge wire is typically used for installing thermostats?
|
18 gauge
|
|
What is the primary to secondary winding ratio of a transformer with a primary voltage of 120 and a secondary voltage of 24?
|
5:1
|
|
What units of measurement do we use to measure gas and static pressure?
|
Inches of water column
|
|
What component does the transformer supply power to?
|
Control Board
|
|
What is the one item that a technician does not need to know when replacing a transformer?
|
Wire size
|
|
Why is it important to level a digital thermostat?
|
Aesthetics
|
|
What type of pressure does the inducer motor create inside the heat exchanger of an 80% furnace?
|
Negative
|
|
What does the high limit switch do?
|
Locks down furnace to prevent heat exchanger overheating
|
|
Which grade steel wool is used to clean a flame sensor?
|
000 |
|
What would the voltage be between R and W during a call for heat?
|
24V
|
|
When should a furnace filter be changed?
|
When it is dirty
|
|
What is the color of the control wire used to represent heat?
|
White |
|
With the system operating: which meter setting is used to check the flame sensor?
|
Micro-Amps DC
|
|
What is the applied voltage for the pressure switch?
|
24V |
|
Which tool is used to check the gas pressure leaving the Gas Valve?
|
Manometer
|
|
Which of the following is not a characteristic of a 90% furnace?
|
Metal flue pipe
|
|
What does a flame sensor do?
|
Proves a flame is present
|
|
Which multi-meter setting can be used to check the High Limit Control?
|
Continuity
|
|
What is the applied voltage for the inducer motor?
|
120V |
|
What type of contacts does a pressure switch have?
|
Normally open |
|
What does the Pressure Switch do?
|
Proves the inducer motor is working
|
|
What color thermostat wire is used for power?
|
Red
|
|
What is the most common manifold gas pressure for natural gas?
|
3.5 inches of water column
|
|
Which multi-meter setting is used to check the capacitor?
|
MFD |
|
How many wires are used to install a conventional thermostat?
|
5 |
|
Which meter setting is used to check the Inducer Motor?
|
Amps |
|
What is the applied voltage for the blower?
|
120V |
|
Choose the component that is wired in series with the high limit control?
|
Roll out switch |
|
What is the formula to calculate wattage of electric heat strips?
|
Volts * Amps = Watts
|
|
What color thermostat wire is used for the blower?
|
Green
|
|
What is the applied voltage for the igniter?
|
120V
|
|
Which manufacturer uses B for the reversing valve (unlike all other manufacturers
|
Rheem/Ruud
|
|
What is the function of a crankcase heater?
|
To prevent refrigerant migration to the compressor during the off cycle.
|
|
When a heat pump goes into defrost mode, what terminal does the defrost board energize to prevent cold air from blowing in the house
|
W |
|
What is the minimum PSI required for a reversing valve sliding mechanism to move?
|
50 PSI |
|
Which TXV is bybassed in Heating mode?
|
Indoor
|
|
If a heat pump is installed in a high snow area, which accessory should be installed
|
Snow legs
|
|
In the heating mode, a dirty filter will cause a heat pump to
|
Lock out on high head pressure
|
|
What terminal designation do all other manufacturers use for the reversing valve
|
O |
|
What is the purpose of an accumulator?
|
To ensure 100% vapor refrigerant enters the compressor
|
|
What color is the reversing valve control wire normally?
|
Orange |
|
A reversing valve will not function properly when
|
Refrigerant level is low
|
|
What is the state of the refrigerant at the true suction port?
|
Low pressure vapor
|
|
Which color wire is not connected to the defrost control board from the air handler?
|
Green |
|
Where is the condenser coil on a heat pump in the heating mode
|
Indoor |
|
In defrost mode, the reversing valve switches to cooling mode and the auxiliary heat is energized. What else happens?
|
The condenser fan is de-energized
|
|
A heat pump outdoor unit must be level. Why?
|
Prevent oil from collecting, To prevent ice buildup, For proper drainage
|
|
How many control wires are needed at minimum to the outdoor unit
|
5 |
|
Which coil receives hot gas refrigerant in cooling mode?
|
Outdoor coil |
|
How many volts are applied to the reversing solenoid?
|
24V |
|
When in the heating mode, where is the discharge gas from the compressor routed.
|
Indoor Coil |
|
What can De-energize in De-frost mode? |
De-frost timer |
|
What is the reason for he 1/4 inch pitch on pvc ventline? |
To allow condensation to fall back to the furnace for draining. |
|
When would you discuss repair v.s. Replacement with the customer? |
For any major repair |
|
What is one of the biggest causes of no charge tickets? |
A tech not doing a thorough assessment of system needs |
|
What is the best method to use for detecting small leaks? |
Electronic leak detector |
|
If we have a low to 0 superheat and a good us cool,what is the cause? |
Dirty filter |
|
Schedule 40 pipe is also known as? |
PVC for the flue pipe |
|
If you discover a need for IAQ products what does it go under? |
Investigative findings |
|
If it is hot What will happen to recovery ? |
It will take longer |
|
What does AFUE stand for |
American Fuel Usage Efficiency |