AC Low service port pressure
#1
07-06-2007, 10:34 PM
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AC Low service port pressure
Disregard, except for history purposes. Actual problem is a couple posts down now.
Regards all.
Rich
Ok, not being a n00b when it comes to forums, I did my due diligance and searched my butt off to find my problem's solution.
Truck: 97 F-150 5.4L Rear wheel drive, extra cab, blah, blah..
K, So I found my low side service port on the accumulator (cylinder on passenger side of firewall), And I checked the pressure.
Ruh, roh!. Pressure reads, when running, full ac on, temp gauge to coldest setting, a whopping 90 PSI.
I don't think the line is blocked because I get a good hiss for a couple seconds when I try to connect the Hose, and gauge.
My questions are multi fold...
A. How can I be sure that the reading is correct, and some *******tard massively over filled it, risking his life in the process, and it's not just something else wrong.
B. If the pressure is correct, is there any point in refilling it with the kit I have, or is it damaged beyone a simple refill.
C. How do I reduce the refrigerant pressure to a normal level (or lower for refilling purposes), without killing myself, or others.... gasp, gasp, oh my ruined lungs.
Dunno what the high side is on the line, I have nothing to measure that, in order to get an idea if they balance out or not.
Any help would be appreciated.
Truck: 97 F-150 5.4L Rear wheel drive, extra cab, blah, blah..
K, So I found my low side service port on the accumulator (cylinder on passenger side of firewall), And I checked the pressure.
Ruh, roh!. Pressure reads, when running, full ac on, temp gauge to coldest setting, a whopping 90 PSI.
I don't think the line is blocked because I get a good hiss for a couple seconds when I try to connect the Hose, and gauge.
My questions are multi fold...
A. How can I be sure that the reading is correct, and some *******tard massively over filled it, risking his life in the process, and it's not just something else wrong.
B. If the pressure is correct, is there any point in refilling it with the kit I have, or is it damaged beyone a simple refill.
C. How do I reduce the refrigerant pressure to a normal level (or lower for refilling purposes), without killing myself, or others.... gasp, gasp, oh my ruined lungs.
Dunno what the high side is on the line, I have nothing to measure that, in order to get an idea if they balance out or not.
Any help would be appreciated.
Rich
Last edited by rich.weber; 07-07-2007 at 12:43 AM.
#2
07-06-2007, 11:09 PM
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disregard. Except for history purposes. I troubleshot past this. Just didn't have the valve open far enough. Next post is where I'm at.
Rich
OK, I just drained some refrigerant by unscrewing the gauge and letting some pressure out.
While the gauge is open it sits at around 25-35, when it is close it climbs back up to around 80 with the AC full on.
I thought I had figured out that it wasn't clogged but it doesn't seem to matter how much I let out (unless it takes a really long time to drain), it keeps jumping back up to 80ish when I close the valve.
While the gauge is open it sits at around 25-35, when it is close it climbs back up to around 80 with the AC full on.
I thought I had figured out that it wasn't clogged but it doesn't seem to matter how much I let out (unless it takes a really long time to drain), it keeps jumping back up to 80ish when I close the valve.
Last edited by rich.weber; 07-07-2007 at 12:46 AM.
#3
07-07-2007, 12:41 AM
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OK, so here's an update.
I bled off all the refrigerant, by opening the valve on the gauge, and walking away, and just prayed I didn't kill any hapless kitties or dogs.
I recharged it per the instructions, and no dice. It's at it's proper charge level, at the ambient temperature (85 degrees was 40-55 psi), I set it to 45 or so.
Letting the AC go full blast during the whole process to get accurate gauge measurements.
It just doesn't get cold.
What should be my next thing to check?
How do I ensure the compressor is working, and doors etc?
Regards,
Rich
I bled off all the refrigerant, by opening the valve on the gauge, and walking away, and just prayed I didn't kill any hapless kitties or dogs.
I recharged it per the instructions, and no dice. It's at it's proper charge level, at the ambient temperature (85 degrees was 40-55 psi), I set it to 45 or so.
Letting the AC go full blast during the whole process to get accurate gauge measurements.
It just doesn't get cold.
What should be my next thing to check?
How do I ensure the compressor is working, and doors etc?
Regards,
Rich
#4
07-07-2007, 07:19 AM
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If your compressor isn't working, the static pressure is SUPPOSED to be high, typically 80-120 psi, depending on the underhood ambient temp.
You just emptied a well-charged system (the tree-hugging hippie-crits and the eco-***** will be stopping by later) and then under recharged it.
Now you have two problems: A compressor that doesn't work and an undercharged system.
Get a real manifold gauge set. The low-side only gauges are more trouble than they're worth.
Fix the compressor engagement fault (original problem) and get it recharged to the proper level.
Read the threads in this sub-forum in which I've posted for the last couple of weeks. I've recently gone over all this and have at least once, described the complete circuit and how it works.
Steve
You just emptied a well-charged system (the tree-hugging hippie-crits and the eco-***** will be stopping by later) and then under recharged it.
Now you have two problems: A compressor that doesn't work and an undercharged system.
Get a real manifold gauge set. The low-side only gauges are more trouble than they're worth.
Fix the compressor engagement fault (original problem) and get it recharged to the proper level.
Read the threads in this sub-forum in which I've posted for the last couple of weeks. I've recently gone over all this and have at least once, described the complete circuit and how it works.
Steve
Last edited by projectSHO89; 07-07-2007 at 07:27 AM.
#6
07-07-2007, 02:14 PM
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Originally Posted by projectSHO89
If your compressor isn't working, the static pressure is SUPPOSED to be high, typically 80-120 psi, depending on the underhood ambient temp.
You just emptied a well-charged system (the tree-hugging hippie-crits and the eco-***** will be stopping by later) and then under recharged it.
Now you have two problems: A compressor that doesn't work and an undercharged system.
Get a real manifold gauge set. The low-side only gauges are more trouble than they're worth.
Fix the compressor engagement fault (original problem) and get it recharged to the proper level.
Read the threads in this sub-forum in which I've posted for the last couple of weeks. I've recently gone over all this and have at least once, described the complete circuit and how it works.
Steve
You just emptied a well-charged system (the tree-hugging hippie-crits and the eco-***** will be stopping by later) and then under recharged it.
Now you have two problems: A compressor that doesn't work and an undercharged system.
Get a real manifold gauge set. The low-side only gauges are more trouble than they're worth.
Fix the compressor engagement fault (original problem) and get it recharged to the proper level.
Read the threads in this sub-forum in which I've posted for the last couple of weeks. I've recently gone over all this and have at least once, described the complete circuit and how it works.
Steve
So, no way to know right now.
Since it's undercharged, the clutch won't engage, and the pressure will not drop down to it's actual low side pressure. Get some real gauges to see what it's actually at on the high side, and determine if it's high enough to engage the clutch. Fill it to the proper level, and see if the clutch engages, if not either the clutch or compressor is bad. Could be that the 90 PSI I was reading was actually too low to engage the clutch and lower the reading to the actual low side pressure. After all, when I first took the measurement, the ambient temp was pretty high.
Am I reading into that correctly? I'll go read your other threads.
thanks.
Rich.
Last edited by rich.weber; 07-07-2007 at 02:16 PM.
