The condenser is not part of the radiator. They are two seperate units mounted near each other. The radiator runs antifreeze/coolant (liquid) through it, circulated by thewater pump,to regulate the temperature of the engine. This is done by the air flowing across it, either by driving down the road or by the fan pulling it through. The condenser works in much the same way. An A/C system is pretty simple really. Basically speaking, it works like this:

An A/C system consists of 5 basic parts: The compressor, condensor, expansion valve, evaporator, and, of course, refrigerant. A pump, in this case the A/C compressor, powerd by the engine via a drive belt, pumps refigerant (R134A, exists in bothgas and liquid forms inside the system, depending on pressure and temperature) through a tube to the condenser, mounted at the front of the vehicle, usually in front of the radiator. As the refigerant leaves the compressor, it is heated past the boiling point and vaporizes due to the pumping (compression) process (basic physics, as pressure increases so does temperature), so the condenser is essential. The condenser is a heat exchanger, just like the radiator, and drops the temperature of the refrigerant below boiling, condensing it back into a liquid. Fans pull air through the condenser (and affectively the radiator) to cool the refrigerant inside. The fans cycle to regulate the temperature and pressure of the gas/liquid to maintain this process. Believe it or not, you would not want to allow the fans to just run indefinately for maximum effectiveness. If the refrigerant gets too cold, it can freeze up, or at least be too cold for the next step in the process to occur. Upon leaving the condenser, it travels to the expansion valve, where the pressure of the refrigerant is reduced allowing it to revert to a gas. This reduction in pressure also greatly reduces the temperature (remember, basic physiscs). Next it travels to the evaporator, behind the dashboard. The evaporator is another heat exchanger, except this time it is taking heat, not releasing heat as the condenser and radiator both do. The blower fan, which blows the air you feel in the car, blows air across the evaporator, cooling the air and heating the refrigerant. As the air cools, it loses it's ability to hold moisture. That is why they call it "Air Conditioning", not just air cooling. It not only cools the air, but dehumidifies it also. This is also why you see a puddle of water on the ground when using the A/C, the water takenfrom the air in the car collects on the evaporator and is drained out onto the ground. ButI digress. The refigerant heats up from absorbing the heat from the air blown across it, and begins to boil. If it was too cold, say from the fans running too long and over cooling it at the condenser, it would not boil, and this step would be lost. The gas returns to the compressor and the entire process starts over agian. If it were still a liquid, the compressor would not be ablt to pump it, and the process would break down. There are pressure and temerature sensors in the system which monitor the state of the refigerant. The fans are controlled by a microprocessor to keep the pressure correct.
Simply stated, that is why the fans cycle on an doff so much. Hope this clears things up.

 

Thanks for reminding me whyphysics was my favorite high school class. Great explanation - no need for a diagram!

 

Hi Im from the Philippines.

After I purchased a used outlander '07 last week I noticed that the a/c blower makes a loud noise (its like a sound of an airplane's engine)even when its on the 1st notch. Its been going on like this until last night, I went to my friend's place to have my aircon blower assessed and its quiet when the condenser is doing its job....all the time. This morning its still quiet. I guess it got shy.

but tonight the problem went back. Is there a sensor that sense the temperature of the engine to let the blower work faster? I can feel the air blower beside the engine is much more faster and its noisy.

I asked my service advisor he said its normal for Outlanders to have a loud blower. Is that so? I never purchased a mitsubishi before and is having doubts of its blower.

 

I've never had any vehicle that's noisy as this 09 outlander but I can deal with that. Oh yes, this is our fist Mitsu as well. From what I've read, it's normal for 1st and 2nd gen. 18k miles and so far so good, no issues at all..knock on wood.