Question

1. in a common residential forced - air furnace, heat is transferred from the ______.

a) air to the heat exchangers
b) natural gas or oil to the conditioned space
c) heat exchangers to the air
d) refrigerant to the outdoor air

1. water or steam is often used in heating systems as a(n) ______.

a) heat - exchange medium
b) combustion byproduct
c) fuel
d) evaporator

1. the term mechanical refrigeration cycle refers to ______.

a) mobile refrigeration equipment
b) the process by which refrigerant moves through a piping system
c) the process by which circulating refrigerant absorbs heat in one location and moves it to another location
d) the process by which refrigerant is reclaimed

1. the expansion device in the mechanical refrigeration cycle ______.

a) lowers the refrigerant pressure at the condenser outlet
b) raises the refrigerant pressure entering the evaporator
c) raises the refrigerant pressure at the condenser inlet
d) lowers the refrigerant pressure entering the evaporator

1. in a typical mechanical refrigeration system, heat is transferred from the indoor air to the refrigerant at the ______.

a) condenser
b) compressor
c) evaporator
d) furnace

1. an erv uses cooled or heated air exiting the building to ______.

a) operate pneumatic tools
b) heat domestic water
c) pressurize other parts of a building
d) pre - condition fresh air being forced into the occupied space

introduction to hvacr module 03101 practice exam
note: this exam is not eligible for a credential.
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Explanation:

Question 6

In a forced - air furnace, the heat source (natural gas or oil) is burned, and heat is transferred from the heat exchangers (where the heat from the combustion is transferred to the air) to the air that is then circulated to the conditioned space. Wait, no, let's re - think. The heat is transferred from the heat exchangers to the air. Wait, the options: a) air to heat exchangers - no, heat flows from hot to cold. The heat exchangers get heat from the combustion of natural gas or oil, then transfer heat to the air. Wait, the question is "heat is transferred from the _____". The heat exchangers have heat (from the fuel combustion), and then transfer it to the air. So the correct option is c) heat exchangers to the air. Wait, let's check the options again:

a) air to the heat exchangers - air is cooler, so heat would not flow from air to heat exchangers.

b) natural gas or oil to the conditioned space - natural gas/oil is burned, heat is transferred to heat exchangers first, not directly to conditioned space.

c) heat exchangers to the air - heat exchangers are hot (from fuel combustion), air is cool, so heat transfers from heat exchangers to air.

d) refrigerant to the outdoor air - forced - air furnaces (non - refrigeration based for heating, usually) don't use refrigerant for heating in the same way. So the answer is c.

Water or steam is used to carry heat from one place to another in heating systems. A heat - exchange medium is a substance that transfers heat between two systems. Combustion byproduct is something like CO₂ from burning, water/steam is not a byproduct in heating (it's a medium). Fuel is what is burned (like gas, oil), water/steam is not fuel. Evaporator is a component in refrigeration, not related to water/steam in heating. So water/steam is a heat - exchange medium.

The mechanical refrigeration cycle is the process where refrigerant circulates, absorbs heat in one place (evaporator) and releases it in another (condenser). Option a: mobile refrigeration equipment is just a type of equipment, not the cycle. Option b: just moving through piping is not the cycle, the cycle involves heat transfer. Option c: describes the process of refrigerant absorbing heat in one location and moving it to another, which is the refrigeration cycle. Option d: reclaiming refrigerant is not the cycle. So the answer is c.

Answer:

c. heat exchangers to the air

Question 7