A/C Problem

[Racer Brown]

On my trip to the coast last week, I had an A/C problem pop up. On the way down, the longer it was on, the warmer it got. To me, this means it was low on Freon. By the time we had gotten to Hatteras, it had frozen up. I left the truck running while we went in to get a slip for the boat and when I came back out, there was a big puddle of water under the truck in the area of the evaporator and the A/C was no longer working. Again, I figured it was low on freon and had frozen up. I hooked the gauges up to it the other day and tried to charge the system. While I was charging it, it seemed as though it was building up too much pressure and was "poping off" at the compressor? Is there a high pressure pop off valve on these compressors? Anyway, it is cooling again but the low side pressure is still not where it's suppose to be. Seems as though it is cycling on and off. Is this normal for this system? Does this thing have an expansion valve or orfice tube to meter refrigerent? And no, I didn't check the high side yet. Guess I should though. That'll tell me whether there is a restriction in the system or not. Any other thoughts on this from you experienced "frig" guys? See Ya!... ... ... ... . Racer

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Ken-1993 W350, Cummins TD, 5 Speed, 4X4, Club Cab, LE, K&N, Straight Pipe, 4:10s.
http://users. lynchburg.net/ken0069

 

[CrewCabDiesel]

Racer, have you checked you condenser to see if it is pluged with bugs and other crap? Also check and make sure the your fan clutch is working correctly. Either one can cause extreme high pressures on the high side of the AC.
Kyle

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1985 DODGE 1 ton Crew Cab W/8' box converted to 4X4 in 1999. Upgraged to a non-intercooled 1991 Cummins Turbo diesel & rebuilt 5 speed Getrag in January 2001. Freshly rebuilt and Balanced Cummins, Rebuilt NP205, Rebuilt Injector pump and tweaked, Matched Injectors, 3" New Mandrel Bent Exhaust,no muffler, Borgeson Steering Shaft, K&N Air Filter, 3:54 gears, limited slip rear end, 16" Goodyear GSA Wranglers, 16K Reese 5th Wheel Hitch,and LE Package, OEM Cruise Control, All New R134A AC, and a Sony CD Stereo. If you want to know why I did all of this, 3 kids and I can't stand F**d and Ch**y. Kyle Hoover ,Fruitport, MI.

 

[sam peterson]

anytime you get a large volumn of water running out of the evap case tell you the system was not out of refrigerant. sounds like the compressor wasn't cycling and the evap was building up ice. high pressures can be caused by over charging or low airflow across the condensor. ---Sam

 

[andyr]

My 93 does the same thing. Had a friend tell me the only time he sees water come out if the A/C is when it is stopped. Which makes sense; because on stop and go driving it does fine but on long rides it loses its cool. Have not done anything to pursue it any further however.

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'93 D250 CC Tweaked pump and nozzles; nv4500 5spd straight exhaust grover air horm

 

[Eric_77]

Had the same problem on my 92 and found to make it cold in truck I had to turn the heat on. Sounds wierd but the heat kept the evaporator from freezing up and then it blew cold air. Only happened one summer and been fine since. I never messed with my freon. Truck has since been "retired" to local use so never runs more than an hour at a time.

Just out of curosity if you are not an A/C man how did you get R-12? personal stockpile?

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Eric Kelcher
92 W250 stock 4spd/auto 3. 54
96 2500 extd SLT Diesel Dynanics fuel pump plate; auto with DD shift kit(?) Dun-Rite TC; 3. 54 posi; K&N airfliter; Boost, transmission temp, EGT guages waiting for nice day; 192K
13. 5k 33'utility trailer 19' Galaxie runabout

 

[Racer Brown]

You guessed it on the R-12. #ad
I bought a 30lb bottle backin 92 at $280 and you didn't need the EPA's blessings to purchase it then either. I do have the necessary certs to purchase it though. I'm EPA certified to work on industrial systems also but the 12 is a "stockpile"! That system on my truck is cycling on and off constantly. Some of the newer systems do that as the expansion valve will meter the refrigerant as needed and it will hold the pressure for a good while. Once it has leaked below a certian pressure, it will engage the clutch and pump it up agan, then cut off again and bleed down. I'll find out next week as we plan another trip to the coast and that'll tell the tale as it's a 6 hour drive. Later, Racer

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Ken-1993 W350, Cummins TD, 5 Speed, 4X4, Club Cab, LE, K&N, ISSPRO Boost & Pyro, SunPro Oil Pressure & Water Temp, Straight Pipe, 4:10s.
http://users. lynchburg.net/ken0069