What’s your honest A/C temp?

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Joshua Keith

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I just installed a Sanden compressor and so far I’m not too happy with it at idle. I’m
Getting 40 with low setting and about 60 on high setting. I’m curious to what you guys are getting at the vents with the fan on HIGH. I know the aftermarket vintage air will freeze you out,but I’m more curious with the stock a/c guys. Post a pic of your A/C vent temp on high, at idle, and with the outside temperature. Let’s compare!
 

Craig 85

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Here's the temp of my truck with a Sanden compressor, but OEM system. Outside temp of probably 70 degrees when I took this. My truck has a 195 thermostat.

Now that I've had an opportunity to drive my truck this summer after the install, here's what I noticed. Temps outside have been 90 or higher lately. I have no problem keeping the A/C at this temp as long as I'm moving. In fact, once the interior is cooled down, I usually run the A/C on Max mode with the temp set even with the Max A/C words and the fan on 2.

At idle things change with outside temps being above 90. My truck will normal run at 195-200 degrees while driving. At idle in drive, it creeps to 210 for red lights. Usually, the A/C will stay cool for the cycle of the lights. Recently, I've been in some heavy stop and go traffic and engine temps have run as high as 235 for short periods. The A/C really hates this and starts to warm. One of my problems is I have no carpet or headliner. Just sound deadener (cuts vibration, not heat).

Just this past week I hooked up the factory electric fan. It has helped with idle temps in stop and go traffic and keeps the truck running right at 210. This has helped with keeping the A/C cool during long periods of idle.

I'll throw my temp gauge in the truck the next time I drive it and let you know what happens.

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dvdswan

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60* is not terrible for the SB. Be glad you don't have a sub or blazer. I would look at the fan clutch to make sure its pulling enough air through the condenser/radiator at idle.

Best way to cool down the interior after its been sitting in the sun is place it on normal a/c on high with the windows down. Blow the hot air out for about 1 minute, then roll windows up and keep on normal, after a couple more minutes then move to max a/c.

If its on max all the time all you are doing it forcing hot interior air through the evap core at start up.
 

austinado16

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Dave's advice on the fan clutch is correct. In fact, unless it's new, I'd purchase a new heavy duty rated one. Also, if you can find a better fan, that would be a nice upgrade. Fan shroud is a big deal as well, it should come rearward enough that at least half of the fan pitch is inside the shroud. The leading half of the pitch is scooping air, the rear portion of the pitch is "slinging" air off the blade. If you can improve the efficiency here, you'll see a benefit where you live! Also, less anti-freeze in the summer, in your coolant ratio. Or add "Water Wetter" type products to the coolant. And of course, radiator internal core condition is a huge deal.

Can't help with temp gauge readings, sorry. I converted to R134a back in 2005. Still running the OE compressor, but I've replaced it. I have a 454 pusher fan out in front, 454 (big) fan, and the long 454 radiator. Out on the freeway, with the rear a/c on low fan speed, and the front a/c on "max" and fan speed 1, the interior will typically get too cold, even in temps around 100*F. It continues to cool well in traffic, but once completely stopped and idling, like sitting in a parking lot talking, or waiting for a food order, the cooling ability drops off pretty rapidly, even with the pusher fan running. It may be a can of refrigerant low atm, but it's fine in our local temps, so I'm not worried about it.
 
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Wrong type of truck, but the same components. Was blowing about 58° the day I charged the stone stock system to see how it did. It was mid 90's and very humid. Blower on high.

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On cooler days, like 80-ish, it blows around 50° at idle. A little cooler while driving.
 

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Whilst at the beach at 90-100 Temps, the compressor in front and rear AC suburban decided to be my buddy and blow out what felt like 60 degree air. Definitely was nice considering there was times I was sitting at lights with the brake pedal on.

Only thing I'll say is truck runs even on super hot days at 160-170, at a dead stop, truck idling, ac running, engine temp will rise to 190, and it's effectiveness kinda Peters out.
 
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I got me a front A/C only Suburban with non tinted glass. I have never bothered recharging the A/C since I've owned it because it did basically jack **** even when fully charged and recently converted. Drive around in a 50 foot long magnifying glass and tell me how good a little 50 degree air blowing on your chest feels. Might as well roll them windows down before the greenhouse effect has a chance to kick in
 

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I got me a front A/C only Suburban with non tinted glass. I have never bothered recharging the A/C since I've owned it because it did basically jack **** even when fully charged and recently converted. Drive around in a 50 foot long magnifying glass and tell me how good a little 50 degree air blowing on your chest feels. Might as well roll them windows down before the greenhouse effect has a chance to kick in
I've learned, the whole gimmick to AC in a old burb is,

Step 1. Roll down all the windows immediately, maybe change shirts because it's hotter than Satan's balls in there :flamingdevil:

Step 2. Drive down the road with windows down, and turn on AC.
(Optional) put your hand on the vent and tell yourself it's cooler than the outside temp.

Step 3. Painfully roll all the windows up (if it's got power windows, you understand), and sweat like a pig as the front and rear AC desperately attempts to cool the cab off now that you've released Satan's hot fart out if the cab

Step 4. You've arrived at your destination, the truck is now cool, but it's time to turn it off and go back to step 1 when you're done shopping.

Oh, and if you're like most of us, step 2a is feverishly claw and bat at the AC control, putting it at max and full AC, despite it feeling like a light breeze.


It's only really pleasant on long trips.
 
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Vbb199

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Dad claims my old girl used to pump out icey cold AC once upon time, but that was also pre 2005, and that was also on R12 refrigerant.
 

Joshua Keith

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Here's the temp of my truck with a Sanden compressor, but OEM system. Outside temp of probably 70 degrees when I took this. My truck has a 195 thermostat.

Now that I've had an opportunity to drive my truck this summer after the install, here's what I noticed. Temps outside have been 90 or higher lately. I have no problem keeping the A/C at this temp as long as I'm moving. In fact, once the interior is cooled down, I usually run the A/C on Max mode with the temp set even with the Max A/C words and the fan on 2.

At idle things change with outside temps being above 90. My truck will normal run at 195-200 degrees while driving. At idle in drive, it creeps to 210 for red lights. Usually, the A/C will stay cool for the cycle of the lights. Recently, I've been in some heavy stop and go traffic and engine temps have run as high as 235 for short periods. The A/C really hates this and starts to warm. One of my problems is I have no carpet or headliner. Just sound deadener (cuts vibration, not heat).

Just this past week I hooked up the factory electric fan. It has helped with idle temps in stop and go traffic and keeps the truck running right at 210. This has helped with keeping the A/C cool during long periods of idle.

I'll throw my temp gauge in the truck the next time I drive it and let you know what happens.

You must be registered for see images attach

sounds like that truck of yours will freeze you out! Well done! I haven’t had the chance to drive it around yet, but It does start to get colder with the higher RPMs. I still have the original 2 core with a 5 blade clutch fan. Any of you guys running an aftermarket carb? Do you have an idle increase solenoid attached?
 

Craig 85

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So I thought I'd give you an update since it's 100 here today, 19% humidity. With the truck warmed up 195-210 degrees, the A/C on Max was producing 60 degree air, maybe just a hair higher at idle.

A couple thoughts. The Max position probably does an 80/20 split of inside to to outside air as the baffle under the cowl does not actually seal. My truck does not currently have insulation, so I get a lot of radiant heat from the floors. So realistically the fact it is producing 60 degree air is pretty good since you are constantly adding 40 degree hotter ambient air to the system.

I had a few of these trucks when they were new and had R-12. They definitely ran colder than my updated 134 system.
 

Joshua Keith

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So I thought I'd give you an update since it's 100 here today, 19% humidity. With the truck warmed up 195-210 degrees, the A/C on Max was producing 60 degree air, maybe just a hair higher at idle.

A couple thoughts. The Max position probably does an 80/20 split of inside to to outside air as the baffle under the cowl does not actually seal. My truck does not currently have insulation, so I get a lot of radiant heat from the floors. So realistically the fact it is producing 60 degree air is pretty good since you are constantly adding 40 degree hotter ambient air to the system.

I had a few of these trucks when they were new and had R-12. They definitely ran colder than my updated 134 system.

that’s not bad at all! It seems we’re in the same ball park. At idle, about 60 degrees when it’s warmed to about 200. I wonder if sealing off that cowl flapper would make any difference.
 

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My 91 burb would be right around 45-50 idle 3+ hours in 100+ heat with recirc on. Otherwise in reasonable conditions 37ish
 

Craig 85

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I wonder if sealing off that cowl flapper would make any difference.

I don't have a picture, but the flapper is just a piece of plastic. Not really designed to fit flush with the inner firewall. the flapper is inside the cowl near the yellow arrow. To seal it off you would only be pulling air from inside the cab. You would have to find a way to permanently hold open the door on the right kick panel.

My 91 burb would be right around 45-50 idle 3+ hours in 100+ heat with recirc on. Otherwise in reasonable conditions 37ish

I only took a short 15-20 minute trip. Last week when I drove the truck for about 40 minutes straight, it did a much better job maintaining the cooler temps.

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