General
Heat Pumps
Electric Heaters
Troubleshooting
History of HVAC
100

what you find across a closed switch

What is 0v

100

what you find on the R terminal

What is input control voltage

100
How are electric heaters energized
Sequencer or contactor
100
If voltage is read across a fuse what does this indicate
The fuse is blown
100
First major railway distribution point in the U.S. for fresh food
Chicago
200

additional heat added to refrigerant after it begins to boil

What is superheat

200
Heart of the heat pump
Reversing valve
200
What is balance point
When heat is being added to the structure, which matches what is being lost
200
How could a technician determine if a heat pump reversing valve is defective
Temperature differences (on true suction)
200
What year was the first known artificial refrigeration system discovered
1755
300

it closes in the thermostat when the temperature rises

What is a thermal switch

300
Design conditions for a heat pump
Indoor 70F. Outdoor 45F
300
When is it necessary to energize the electric heaters
Balance point or defrost
300
A abnormally low suction pressure in the heat pump mode of operation could indicate _________
Dirty outdoor coil
300
The reason that the HVAC industry exists today
A quest to assist in industrial processes
400

what is used to pressurize a system when you are looking for a leak

What is dry nitrogen

400
When is the reversing valve energized
Depends of the manufacturer
400
Can a electric heater be re-strug
Yes
400
If a gas furnace starts, runs for a few seconds, shuts down, and repeats this process, the problem is most likely
Defective flame sensor/rectification
400
The person was considered to be the Visionary for A/C
Dr. John Gorrie
500

what do you find ACROSS an open switch

What is applied voltage

500
What causes the reversing valve to shift
Pressure
500
When is an electric heater referenced as a emergency heater
When the heat pump has failed
500
Given a three ton A/C system operating normally, the delta H should be
6.67
500
In what year did Willis Carrier patent A/C and what was it first called
1908 / Apparatus for treating air
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