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Flashcards in General Knowledge Deck (18)
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The evaporator in the refrigeration system:

Absorbs heat from the conditioned space.

1

Heat that is added to the refrigerant after it has all vaporized is called:

Superheat.

2

The refrigerant leaving the compressor is often referred to as:

Hot Gas.

3

If the evaporator temperature is below 32* F, there must be some provision for:

Defrost

4

The TXV is located between:

Condenser and Evaporator.

5

Off-cycle defrost occurs:

From the space temperature when the system is shut down.

6

A saturation vapor condition exists when:

All of the liquid has boiled into a vapor.

7

For low-temperature refrigeration, ________ from the compressor discharge line may be used to defrost the evaporator.

Hot gas.

8

Refrigeration in the evaporator..

Changes from a liquid to a vapor.

9

What does a high superheat indicate?

Low on refrigerant.

10

A low evaporator superheat indicates..

Overcharged or restriction from debris.

11

Why is a multi-circuit evaporator used?

To keep excessive pressure drop from occurring in the evaporator.

12

What is air conditioning?

The process of treating air to simultaneously control its Temperature, Humidity, Cleanliness, and Distribution to meet the requirements of the conditioned space.

13

The human body gives off heat in three forms. What are they?

-Convection.
-Evaporation.
-Radiation.

14

What are the three conditions which affect the body in terms of rejecting heat?

-Temperature.
-Relative Humidity.
-Air Motion.

15

What is Relative Humidity?

It's the measure of how much moisture is in the air at a given temperature.

16

In terms of relative humidity, cool air..

Has less capacity to hold moisture so the human body will evaporate more moisture to cool air.

17

In terms of relative humidity, warm air..

Has a greater ability to hold moisture, so the human body will not be able to evaporate as much moisture.