Well, let's take a look at thermodynamics. Thermal energy will flow from hot to less hot or cold if you will. If you have two objects at the same temp sitting in close proximity, nothing will happen. If one is cooler than the other, the the hotter of the two will transfer heat to the cooler object until both are at equilibruim, so, if you have a car with a cooling system at operating temp, the heat transfer will be affected by the temp of the other part of the system, namely the ambient air. Now we all know that it's much nicer to have a fan blowing cool air in your face rather than hot air. IF the air is dry and you're sweating, the evaporation of the sweat will help cool you down. If the air is damp, we all know what that feels like. Could be they called the evaporator in A/C systems that name for that reason. At any rate, when, the air that is "cooling" your engine is almost as hot as the coolant air interface AKA radiator, very little heat transfer is going to take place. If the ambient air is cooler or cold, you will get a much imporved heat transfer. That's why we have thermostats. We all know it takes a bit longer in the winter to get things up to operating temp, when in the summer on a 100 degree day, the car is at operating temp by the time you roll down the window. Anyway, when it's hot out, the cooling system has to work a lot harder to move the heat than when it's cool. This is directly related to the ambient temp of the air passing thru the radiator and the condenser. BTW, why do you think the condenser is in front of the radiator?? 50 points for the correct answer...

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Jeff Lawrence
1989 300e
2000 Dodge Grand Caravan SE