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Got this idea from a guy in Phoenix. Last Sunday, I painted the center top of my hard top white.

It cut down on the heat inside tremendously. Carting my 3 kids around without adequate air conditioning in the 4 door has been brutal on them. Even though it's cooled down quite a bit since last week due to the hurricane, one of my coworkers noticed how it was less "oven-like" inside and how quickly the recirculating air conditioning cooled it down inside.

I cleaned it, taped it all off several inches in from the edges, sanded it down, cleaned it again and sprayed 3 coats of Rust-Oleum gloss white. I put it out in the driveway after it was starting to set up and when it was dry, the difference to the touch between the white and black was unbelievable. I want to hit it with an infrared thermometer just for curiosity's sake.

From the sides, at ground level, you wouldn't even know it was done. But the slight rake I have, I'm sure it can be seen from the front driving down the road.















 

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Here are 3 more pics I shot at work. The first two are with my iphone at eye level. The last is holding it as high as I can (I'm 5'10").





 

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I keep considering doing this too. Tired of waiting over 4 months for a northern every year.

Looks like a really clean job. Nice stinger too. :beer:
 

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Awesome job Tehiv.
If you are doubting this theory, On a hot day, go put your hand on a white car and a black car. You might be buying some paint soon,lol.
 

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I should have patened this 2 plus years ago. At jk-f they treated me like a tard for doing it but the temp difference is amazing! Looks good!
 

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Also once you do the resistor mod to the txv it will be like an ice box in there, well maybe not that cold but a hell of a lot colder than it was getting.
 

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Awesome job Tehiv.
If you are doubting this theory, On a hot day, go put your hand on a white car and a black car. You might be buying some paint soon,lol.
Now three years in Texas and the prior thirteen years in Florida my vehicles are white... even the JK, but... comes with a black top. I wish they made a white softtop.
 

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Every now and then you can get some useful information out of the flock...

the A/C issue is the fact the due to the way EPA measures fuel economy car manufacturers are required to test MPG with the A/C on.. so they tend to cycle the unit out when the output vent temp is around 50-55 degrees which is cool but not the ice bone chilling cold that some (including me) like...

Jeep uses an H-valve (a fake TxV sort of) and an evaporator temperature sensor to control the compressor cycling...

the evaporator temperature sensor is a wierd value thermistor... its not a standard 10k device... however it can be skewed allowing the compressor to stay in longer...

these devices typically have a 5% tolerance level in them which can result in different people having different results...

I ended up popping a 20K ohm resistor across (in parallel) with my sensor and am now getting 40-45 degree air on average from the vents.. an 18K ohm resistor dropped the vent temp to the high 30's however It also started to freeze the evaporator core.. so I backed off a little...
MUCH better than the original 50+ degree air..

because of the differences in the tolerances of the sensors you may need t play with tyhe resistor values a little to get it calibrated just right.... the lower the value resistor the colder the air although more risk of freeze-up and freezing up solid *CAN* damage the air-conditioner if left out of control.. the higher value resistor the less effect it will have...

id say 15k-25k ohms is the range needed..

-Christopher
Sounds like its time to invest in a rheostat!

http://ca.digikey.com/1/1/57603-pot-25k-ohm-carbon-2w-rv4laysa253a.html

http://ca.digikey.com/1/1/53237-pot-25k-ohm-5w-wirewound-w-hrdwa-026tb32r253b1a1.html
 

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Awesome job Tehiv.
If you are doubting this theory, On a hot day, go put your hand on a white car and a black car. You might be buying some paint soon,lol.
Here's an amazing comparison too.... the difference between a black car with tan interior and NO tinted windows and a dark gray Jeep with black interior and factory tinted windows.
 

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Nice Job!

Been considering do this. Showed my painter the pics and told him to be ready to do this soon.

May also do the Rotopax conversion on my windows as well.
 

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I repainted my whole jeep from flack to desert tan, and i have to admit it's like having a whole new jeep. living in AZ sucks in the summer, but this summer is easier to live through.
 

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May also do the Rotopax conversion on my windows as well.
What's this? Searched to no avail really. Rotopax makes fuel containers?

Anywho might have to try that resistor mod. Though my jeeps rescue green ain't so bad! :thefinger: Still gets hot though.
 

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If I remember correctly I am running a 17k ohm resistor and the output air from the vents is 32 degrees, sometimes lower and has yet to freeze up. With the painted top and my colder output temps it is alot more comfy and no longer have to listen to it blasting on high. On a side note the ac output from the vents would never get below 54 degrees before the mod. So it is worth the 10 cents and two minutes for colder air. Hijack over...
 
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