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My dads 1994 aerostar is giving him issues with the A/C. He uses it as a work vehicle (panel van style) and uses it daily with no working A/C (90*+ temps outside)
It blows warm/hot air through the vents so he went and bought the do it yourself kits to re-charge the A/C. He charged up the system as best as to what he knows how to as it was his first time trying. And it still blows hot air.....now he was messing with a plug that controls the a/c compressor and when he unplugged it to check the connection and plugged it back in it blew the 20amp fuse under the dash. And has blown several fuses since then messing around with it. Still no cool air and the compressor will turn on for only maybe 30 seconds after putting a new fuse in and then it blows the new fuse.
His system seems to be holding the freon or whatever it may be it just doesn't seem to be pumping it through the system and into the van.
I know absolutly nothing about A/C units so if someone could guide me into trouble shooting this issue that would be great. I feel sorry for my old man having to drive with no A/C and this summer heat. He really can't afford to take it in and have a shop charge him for their service.
Perhaps it has too much freon? I know one time my friends car was doing this. It showed full of freon and wouldn't cool. What we did was on the low pressure side where you fill it up with freon, we pushed the little valve with a standard screw driver while the compressor was on, making it release some of the freon, after that it started to cool.
What plug was he messing with? The one on the compressor or the one on the accumulator, which is a pressure switch. Was the clutch on the compressor engaged before he put the charge in? Will the clutch engage before it blows the fuse?
Blows fuse:
Wireing shorted ? Unplug from compressor-turn on A/C-check for 12VDC at plug.
Compressor clutch shorted out.
Compressor clutch not engaging. ie:Pulls high current,blows fuse.
The freon charge if too high will not blow fuses, but will make V-belts slip.
This may help.
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99.5 F350 XLT Lariat 4X4 AT 4.10 DW CC LB Centurion conversion Garret Turbo, Radio SD &Tape, SP Performance 40-60-80 chip, 100 Gal.Transfer Flow W/Trimax Control Aux. fuel tank. ScanGaugeII, Boost, EGT, Trans. Temp. Oil Temp. Build date 03/99
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ac compressor relay...famous on the chebby's. Should be on one of the inner fenderwells if I remember right. The relay is drawing too many amps. costs about 10 bucks.
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2004 F250 CC FX4 175k miles and counting
reprogrammed egr Innovatives programming
straight piped Airaid intake harpooned tank
If I recall, coolant flows through the heater core all of the time and there's a damper door to divert air around it when not using heat. That damper door is driven by a vacuum motor; there might be a leak in either the motor or the tubing powering it.
How hot is "hot"? You didn't say whether the hot air it's blowing is at radiator temperature or at outdoor air temperature. That could make a difference in where to look for the problem.
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Douglas Campbell, P.E.
1986 Isuzu P'up, 177,673.8 miles.
- Hella headlights (highly recommended)
- DOT C-2 back end (also recommended)
- R-12 air conditioner converted to R-406a. Saved ozone and money
- 4.1:1 final drive converted to 3.4:1. Quieter, better mileage but it's a good thing I live in the flat Midwest.
- 9/22/2007, age 21: Still running well when reluctantly sent away for reincarnation, due to body & frame rust.
I would say its 80-95* air that its blowing. So that would be par with outside temps.
The plug we have pulled to check connection (which is when all the fuse blowing started) was on the accumulator. (I believe it was the accumulator) the black bottle that actually has a site glass on the top? you can see bubbles flowing past it when we were filling it.
lee--when the bubbles disappear--its full--and--the compressor--if it blows the fuse--is probably going south--tooooo much drag from int damage---when a system loses freon--it normally loses oil with it--and after so many refills--no oil left---gooodbye comp-----
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94 f250 idi turbo sc e4od alum fac rims 149,289 --dana 60 frt with posi--10.25 rear w/posi--shouldnt get stuck!! ats turbo 3" parts on--what a diff from stock turbo!!!!!--- also 96 F250 with 305,000 is fixed!!-- 7.3 rattler-also 85 6.9-needs new engine!! tired!!
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... if [the compressor] blows the fuse--is probably going south--tooooo much drag from int damage ...
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True for electrically-driven compressors. Not true for belt-driven automotive compressors. They don't draw more current when the compressor gets worn out and the drag increases, because they only use electricity to pull in the clutch, not to turn the compressor.
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Douglas Campbell, P.E.
1986 Isuzu P'up, 177,673.8 miles.
- Hella headlights (highly recommended)
- DOT C-2 back end (also recommended)
- R-12 air conditioner converted to R-406a. Saved ozone and money
- 4.1:1 final drive converted to 3.4:1. Quieter, better mileage but it's a good thing I live in the flat Midwest.
- 9/22/2007, age 21: Still running well when reluctantly sent away for reincarnation, due to body & frame rust.
Hello, When A system is overcharged it will have a symptom Known as Floodback. It will start to ice up the suction line from evap back to compressor. And will still cool.On a comercial or residential unit. But on your van You might have a Expasion valve problem. Some thing stuck in it like a minute piece metal or slag. or you valves are shot in The compressor. Did you convert to R-134A or is it R-12? 1994 should have been R-134A. You can jump out the pressure control to engage clutch, But you better have a set of guages on it. then you can see what the compressor is doing. and see what pressure is. 35Psi on low side should yield a 40* evap coil. also remember Temperature and Pressure are directly Proportionate. If temp is up pressure is also. never the oppsite. And the condensiong coil when vehicle idle draws heat and then the fans come on. Fords were notorious for O-ring Problems. I had to replace on my 93 Lightning. Hope this help sorry for being long winded.
John
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2004 F-250 Lariat 6.0 Diesel C.C. 4x4. Wedgewood Blue/Arizona Beige. MBRP Catback exhaust, Edge Juice Platinum and loud obnoxious Train horns. Viar 450c (2)slim line 5 gallon tanks with extra fittings for air tools.
Also love my 93 Lightning.
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... if [the compressor] blows the fuse--is probably going south--tooooo much drag from int damage ...
[/ QUOTE ]
True for electrically-driven compressors. Not true for belt-driven automotive compressors. They don't draw more current when the compressor gets worn out and the drag increases, because they only use electricity to pull in the clutch, not to turn the compressor.
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The lack of oil from the escaping freon is still true though and is likely candidate for a dead compressor. Perhaps the heat from the dying compressor overheated the coils in the clutch and they shorted making them draw too much current and blow the fuse.
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2000 F250 CC, PSD, Lariat, 4X4, DP Tuner 80HP PCM, AIS air filter, 4" Magnaflow SS Exhaust, Isspro Overhead Gauges, In-tank mod, Homemade CCV, AIH delete
2004 Honda Pilot EX-L for the wifey
2011 Hyundai Sonata 2.0T
2003 Yamaha Kodiak 450
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deserve neither liberty nor safety." Benjamin Franklin
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LOl or you could all be wrong we've bought a lot of vehicles where we thought the A/C was bad cause it blew hot and full on r-134a and compressor not leaking but think simple before hard, alot of times the hot to cold knob for the ac controls gets warn bad and you may have it set on hot but the control is not moving the temperature. Had this happen on a lot of fords....
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1993 F-250 5-speed 4x4 7.3L Non-turbo Silver/White Standard cab longbed, American Raching 16.5" wheels, brush guard,Loud duals.
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