It appears you are confusing energy transfer by work with energy transfer by heat, starting with the title:
AC compressor adds less heat than is removed during condensation?
The compressor in a refrigeration cycle does not add heat to the refrigerant. Heat is energy transfer due solely to temperature difference.
The compressor adds energy to the refrigerant by means of work, taking low pressure saturated vapor from the evaporator and delivering high pressure superheated vapor to the condenser.
My question is: since heat was added both during the evaporation phase
(from inside the house) and during compression, why should we expect
that more heat is lost during condensation than was added by
Again, heat is not added to the refrigerant by the compressor. Energy is added to the refrigerant by the compressor by means of work, not heat. It is important to understand the difference. Heat is energy transfer due solely to temperature difference.
Overall, the stages are
Energy is transferred to the refrigerant from the cool environment in the form of heat by the evaporator.
The compressor transfers energy to the refrigerant by means of adiabatic work converting the refrigerant from saturated low pressure vapor at the evaporator to superheated vapor (high pressure and temperature) at the condenser.
The condenser transfers energy from the refrigerant to the warm environment by means of heat, converting superheated vapor to saturated liquid.
An expansion valve takes saturated liquid from the condenser and delivers a liquid/vapor mixture to the evaporator with no work or heat transfer.
For conservation of energy the energy extracted from the refrigerant by means of heat in the condenser is the sum of the energy absorbed by the refrigerant by means of heat in the evaporator plus the energy absorbed by the refrigerant by means of work by the compressor, or
You may find the following article helpful: https://en.wikipedia.org/wiki/Heat_pump_and_refrigeration_cycle
I think I still have some confusion. I understand that heat can be
transferred, but can't one also speak of the amount of heat (thermal
energy) in a system?
No you can't think about the amount of heat in a system. Heat is strictly energy transfer due to temperature difference. Things don't "contain" heat. The energy contained in the system is properly called the internal energy of the system, which is the sum of the kinetic and potential energies at the atomic and molecular level.
The term "thermal energy" is often used as synonymously with the kinetic energy component of internal energy, but it is often frowned upon because of being confused with temperature and heat.
And if something causes that to grow through work, then although it
hasn't "transferred heat," is it not appropriate to say that heat was
added in the process?
No, it is not appropriate to say that heat was added to the process. It is appropriate to say that energy was added to the process due to work (energy transfer due to force times displacement) not heat (energy transfer due to temperature difference).
Apart from that, hopefully the rest of my question makes sense.
I will have to reread it since it appears you edited it after I posted my answer.
This will address your edit and the related link.
- The gas is transferred to a compressor, where most of the work is done. The gas is compressed adiabatically, heating it and turning it back to a liquid.
This is at best, sloppy thermodynamics wording and at worst downright wrong. Get yourself a better reference.
First of all, when they say “heating it” they actually mean raise its temperature. But the increase in temperature is due to energy transfer by compression work, not energy transfer by heat. Unfortunately this is not uncommon. Since we are so used to raising the temperature of something by heat transfer, like cooking on a stove, we tend to use the word "heating" as always synonymous with raising temperature. But that is not always the case. Raising the temperature of a gas by compressing it involves no heat transfer.
Secondly, the compressor does not turn the gas "back into a liquid". It takes saturated vapor at the output of the evaporator and raises its temperature and pressure to create superheated vapor for the input to the condenser. See process 1-2 for an ideal (isentropic) compressor in the diagram below taken from the Wikipedia link above. If you Google "Temperature-entropy diagram for refrigeration cycle" to find a multitude of similar diagrams. Nowhere will you see the output of the compressor being a liquid.
- The liquid passes through cooling coils on the outside of the fridge. Because the liquid is now warmer than room temperature, heat is transferred naturally to the room. This is an isobaric compression process.
The superheated vapor, not liquid, is passed through the coils first transferring heat to the room to convert the superheated vapor to saturated vapor (lowering temperature and pressure), as shown in process 2-3 in the figure below, then transferring heat to convert the saturated vapor to saturated liquid at constant temperature and pressure (isothermal and isobaric) as shown in process 3-4 in the figure below.
Hope this helps.