Hello All, I live in a hot part of the U.S. Air conditioning in most cars struggle. This got me to thinking: Let's say I have a 1999 F-350 7.3, would doubling the size of the condenser (leaving all other parts stock) help with this? Any downside?

I know this isn't easy etc. This is more of a theoretical question at this point.

Thanks!

 

not really. a vehicles ac unit will only work so good no matter what you change on it.
you have to remember, your pickup is a large heat magnet. besides heat from engine bay, you have radiant heat from the cab roof, and through the windows.
your truck already has around a 20,000 BTU ac unit in it. that is the size of a normal whole house ac unit for a smaller house.

 

Sorry, I thought I replied to this. Thanks for the response!

Following up: In "recirc" with the temperature turned al the way down, the air conditioning system supplies colder temperatures on cooler days and warmer temperatures on warmer days. This is based on the measured temperature of the output air with the cab at about the same temperature and the sun load about the same. This tells me that there is some part of the HVAC system directly affected by the temperature of the ambient air. The only thing, in "recirc" mode, that directly interfaces with ambient air as part of the air conditioning process, is the condenser . . . and even at that, the mechanical fan assists less on a cooler day while the dashboard temperature is still lower. This tells me that more heat rejected by the condenser into the air passing through equals cooler air output at the dashboard. Based on this, additional rejection capacity should equal cooler dashboard air, so additional condenser capacity created by doubling the size of the condenser would accomplish this . . . right?

 

There are a lot of complicated thermal dynamics in an AC system. The evaporator and condenser can only change temperature within a range. Both work very well when the ambient air and cabin air are cool. Unless you are an AC system designer, knowing the effects of changing the size of either is just a guess. They system needs all components to be sized optimally together. Changing one component may not make it any better.

 

A/C is somewhat more complex but it's also fairly simple. Like a cooling system, it is just taking the heat that is in the cabin and moving that heat to the front of the radiator where it can be cooled again.

Would a bigger radiator help with the engine cooling? Sure, it could, but if there are restrictions that prevent that radiator from doing it's job, then probably not.

The cheapest way to make the A/C more efficient is to look at the air flow going through the cooling units in front of the truck. Is there any way that the air can bypass them? If there is, that needs to be fixed. I worked for a manufacturer that had a huge problem with their A/C systems. Part of the campaign was to seal the places where the air could bleed past the condenser/radiator. The A/C high pressure dropped well over 80-100psi. Just with those small improvement. Hard to believe, but when you see the before/after results, seeing is believing.

I believe a large condenser is not going to hurt any A/C systems and will only make it more efficient.