Ac help
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Joined: Dec 2013
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Ac help
Hi guys I need some AC help I have no idea about anything AC I have a 95 f-150 4x4 with a 302 and I need help charging my AC when I go to charge it says it's full on the gauge. The compressor isn't on.. The compressor will not come on until I run a jumper wire from the plug to the hot post on the battery.. When I manually cut on the compressor the gauge bottoms out.. I'm wondering if I do not have enough to freon in the system to engage the clutch How much freon does this system hold?
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Joined: Jul 2007
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From: Cape Girardeau MO
IIRC, the low pressure cutout for R134 systems should be in the high 20s. If the system hasn't been run and has equalized, should see low-side pressure in the 70s and 80s up to the low-hundred range, very roughly equal to the ambient temperature in Fahrenheit.
This equalized pressure should be enough to engage the compressor momentarily until the low-side pressure drops below its cutout point.
The Freon capacity should be listed on a sticker in the engine bay, typically in the high 2's to low 3's pound range.
Suggest chances are better than average that your system is simply low on Freon, but there could be other issues causing your symptoms. If you're not sure about what you're doing, it may be better to let a professional have a look rather than risk damaging the system or worse yet, yourself.
This equalized pressure should be enough to engage the compressor momentarily until the low-side pressure drops below its cutout point.
The Freon capacity should be listed on a sticker in the engine bay, typically in the high 2's to low 3's pound range.
Suggest chances are better than average that your system is simply low on Freon, but there could be other issues causing your symptoms. If you're not sure about what you're doing, it may be better to let a professional have a look rather than risk damaging the system or worse yet, yourself.
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Joined: May 2013
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From: San Antonio, Texas
To be completely honest. If you really have no idea about anything A/C then I would suggest taking it to a shop.
However, if you really want to do it yourself....
The system capacity is 38 ounces. Hook up the fill tube to the A/C port, hook up the can of freon, but don't puncture the can yet. Start the truck and turn the A/C on. Then puncture the can and start letting freon in. Since you don't know how much, if any, is in there already you're going to have to watch the gauge. As the freon goes in it should get to a point where the compressor starts to cycle on and off. Keep adding freon until the gauge moves up and down as the compressor cycles but still stays in the green the whole time. At that point stop putting freon in. Get in the truck and make sure it's blowing cold.
However, if you really want to do it yourself....
The system capacity is 38 ounces. Hook up the fill tube to the A/C port, hook up the can of freon, but don't puncture the can yet. Start the truck and turn the A/C on. Then puncture the can and start letting freon in. Since you don't know how much, if any, is in there already you're going to have to watch the gauge. As the freon goes in it should get to a point where the compressor starts to cycle on and off. Keep adding freon until the gauge moves up and down as the compressor cycles but still stays in the green the whole time. At that point stop putting freon in. Get in the truck and make sure it's blowing cold.