Air conditioning, NDs, and the Southeast US
#42
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Join Date: Aug 2015
Location: Lakeland Florida 33805
Posts: 78
Total Cats: 2
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My NB has struggled keeping me cool. I also have a small leak in the AC that I cannot find, so even when I hit that sweet spot of refrigerant- it only lasts for ~2 months. I have insulated the floor and trans tunnel very well using a layer of foil backed tar paper stuff for sound deadening, then a layer of foil backed insulation, and in some places I used jute felt over that. I must say the insulation addition was noticeable to me.
I prefer my system slightly overcharged. I usually end up just over 30psi on the low side, with a high idle speed, probably around 2k rpm. I have used Enviro-safe 134a replacement "Freon" and I think it works great, somewhat noticeably better that 134a, but I find myself picking up a can of regular 134a at Walmart to top off when it gets low. I pay $5 for a can at Walmart, the Enviro-safe is not much more money but it takes pre-planning, which I am not so good at. What bothers me about my system is that at full cool settings, with a "hot" cabin" my unit still cycles.... I have not yet diagnosed what is telling the compressor to stop and take a break....
On a hot Florida summer day, my AC is plenty cold if I take a drive at 3pm in the afternoon, when the car was just in the garage or shade. Starting the car when its been in the sun is another story as it takes quite a while to cool down. The vent temps are cold- as low as 36-37 degrees, but it still struggles to cool down a hot car. This leads me to believe its either an air volume thing, or an insulation thing.
My windows are tinted, but with cheap tint. I can actually feel the difference in coolness when I'm in the shade of a cloud, even if its just briefly. My next step is better tint!
I prefer my system slightly overcharged. I usually end up just over 30psi on the low side, with a high idle speed, probably around 2k rpm. I have used Enviro-safe 134a replacement "Freon" and I think it works great, somewhat noticeably better that 134a, but I find myself picking up a can of regular 134a at Walmart to top off when it gets low. I pay $5 for a can at Walmart, the Enviro-safe is not much more money but it takes pre-planning, which I am not so good at. What bothers me about my system is that at full cool settings, with a "hot" cabin" my unit still cycles.... I have not yet diagnosed what is telling the compressor to stop and take a break....
On a hot Florida summer day, my AC is plenty cold if I take a drive at 3pm in the afternoon, when the car was just in the garage or shade. Starting the car when its been in the sun is another story as it takes quite a while to cool down. The vent temps are cold- as low as 36-37 degrees, but it still struggles to cool down a hot car. This leads me to believe its either an air volume thing, or an insulation thing.
My windows are tinted, but with cheap tint. I can actually feel the difference in coolness when I'm in the shade of a cloud, even if its just briefly. My next step is better tint!
#43
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Roger. I'd been trying to figure this out from the FSM, and it wasn't really clear. And, frankly, because of all the issues I've had with my back over the past year, I'm being really careful about bending over / contorting myself into tight spots to examine stuff.
I really do need to pick one up.
6's suggestion about very slightly over-charging the system makes me want to even more.
I really do need to pick one up.
6's suggestion about very slightly over-charging the system makes me want to even more.
https://www.miata.net/garage/heater_cable.html
#48
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Joe, this might help you with the cable adjustment.
https://www.miata.net/garage/heater_cable.html
https://www.miata.net/garage/heater_cable.html
#53
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Join Date: Nov 2008
Location: Tampa, Florida
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Yeah I've had plenty of people try and tell me how my car would be fractionally faster and easier to keep cool on the track if I would just ditch that darn air conditioning. If the car didn't have air conditioning I could set it on fire and use it more often. It's absolutely essential for dehumidifying the air in the cabin and making the car even drivable 6 months out of the year. Unless I'm on the track I don't want to show up anywhere with clothes soggy from sweat. And you can actually die of heat exhaustion sitting in traffic in the car without air conditioning here. It's considered a life support system for 4 months in the summer if you've got a hard top on it.