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Discussion Starter #1
Folks,

I am re-using an old condenser which I have thoroughly flushed inside and cleaned outside.
It all looks nice and clean but the original black paint has mostly come off.
How important is the black paint to the cooling efficiency of the fins.
Is it special or just regular heat resistant black paint?
I see other after market condensers in the original aluminum color which to my mind should be more efficient for cooling than black.

Any insight will be greatly appreciated.

Ta,

Neville.
 

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Maybe for corrosion protection?
 

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I think the paint film would just act as an insulator, hampering heat flow.
 

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A few consideration perhaps

Bare aluminum doesnt stay bare for very long, Aluminum Oxide forms very quickly and in addition to being a very poor conductor of electricity (until you reach its dielectric threshold) it is also a poor conductor of heat. It will tend to increase in thickess (kind of like rust) and eventually will become a severe impediment to efficient thermal transfer between the condensor fins and ambient air.

Why black? Cosmetic and cost probably. I think the paint is there to protect the alum from oxide buildup and eventual rotting of the fins-- the cars have to live everywhere from dry desert to oceanfront and everything in between--

With that technical guess, I;ve seen lots of AL heat transfer devices that are "natural color" -- whether thats a thin conformal coat of a lacquer or otherwise, I dont know.

If it was me, Id use the condenser as is UNLESS I lived in a sea-salt location (ie on or near the beach), or parked the car near an ammonium factory, etc.
 

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In our test measurements, we didn't find a great deal of heat transfer degradation due to aluminum oxide, the film staying rather thin.
 

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Bare aluminum doesnt stay bare for very long, Aluminum Oxide forms very quickly and in addition to being a very poor conductor of electricity (until you reach its dielectric threshold) it is also a poor conductor of heat. It will tend to increase in thickess (kind of like rust) and eventually will become a severe impediment to efficient thermal transfer between the condensor fins and ambient air.

Why black? Cosmetic and cost probably. I think the paint is there to protect the alum from oxide buildup and eventual rotting of the fins-- the cars have to live everywhere from dry desert to oceanfront and everything in between--

With that technical guess, I;ve seen lots of AL heat transfer devices that are "natural color" -- whether thats a thin conformal coat of a lacquer or otherwise, I dont know.

If it was me, Id use the condenser as is UNLESS I lived in a sea-salt location (ie on or near the beach), or parked the car near an ammonium factory, etc.
I would not worry either unless you live by the ocean or something. I have had my p-flow aluminum condenser for years with nothing on it. Yes I live in the desert but no build up of anything. I think the paint reduces efficiency but I could be wrong. Most condensers on new cars are bare aluminum like mine. All my radiators are bare too.

No worries IMO. Only reason it was black was to hide it so it did not show through the grills.
Jason
 

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Discussion Starter #7
Thanks for the input folks.

I will probably lightly spray the condenser black again just for cosmetic value and protection against the odds.

Ta,

Neville.
 
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