AC Pressure Data Please Evaluate
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New User
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AC Pressure Data Please Evaluate
97 F150
Clutch time ON 2 - 3 seconds.
Clutch time OFF 12 seconds.
Off Clutch Low Side 45 psi
On Clutch Low Side 22 psi
Off Clutch High Side 45 psi
On Clutch High Side 75 psi
I put a can of R134 oil and freon in a week ago. Got cold for a while, now blow nothing but warm air.
Wonder if just low or have a leak?
Got to love gauges, more TOOLS!!!
Thanks for input
Richard
Clutch time ON 2 - 3 seconds.
Clutch time OFF 12 seconds.
Off Clutch Low Side 45 psi
On Clutch Low Side 22 psi
Off Clutch High Side 45 psi
On Clutch High Side 75 psi
I put a can of R134 oil and freon in a week ago. Got cold for a while, now blow nothing but warm air.
Wonder if just low or have a leak?
Got to love gauges, more TOOLS!!!
Thanks for input
Richard
Freshman User
Joined: Sep 2004
Posts: 26
Likes: 0
From: Alabama
Richard,
Sounds like low freon. Since you added some & it cooled, then stopped cooling and started cycling on & off rapidly you probably have a leak. Evacuate your system, and pull a vacuum. If it holds a vacuum of around 29 for 10-15 minutes, you probably do not have a leak. If the vacuum falls, replace the o-rings, vacuum to check for leaks again. If no leaks, pull a vacuum for 45 minutes to 1 hour to remove moisture and impurities, then recharge. It should cool then and no quick cycling off & on.
Chuck
Sounds like low freon. Since you added some & it cooled, then stopped cooling and started cycling on & off rapidly you probably have a leak. Evacuate your system, and pull a vacuum. If it holds a vacuum of around 29 for 10-15 minutes, you probably do not have a leak. If the vacuum falls, replace the o-rings, vacuum to check for leaks again. If no leaks, pull a vacuum for 45 minutes to 1 hour to remove moisture and impurities, then recharge. It should cool then and no quick cycling off & on.
Chuck
Junior User
Joined: Jan 2003
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From: St. Louis
If it's low, then you have a leak. From your data, it's definitely low. If you just added freon a week or two ago and it's low again you have a big leak. So don't waste your time evacuating and pulling a vacuum to see if you have a leak because you do. The best way to find a leak is with the freon in the system either check with a refrigerant leak detector or add a dye with a new charge of freon and wait a couple of days to look for dye leakage from the system. Don't forget that when the freon leaks so does the reffrigerant oil so you may find oilly residue around the leak point and you should add some oil with the new freon to replace what was lost. That being said the easiest and best way to get it fixed is to take it to a pro.
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AC Pressure Data Please Evaluate
Ok... added a can of R134a with the leak detection UV kind. No visible leak around hoses. Could be leaking in places where one cannot see.
This time the low pressure jumped to 75 psi and the high side around 75 - 80 psi.
Seems like something is clogged?
thanks
This time the low pressure jumped to 75 psi and the high side around 75 - 80 psi.
Seems like something is clogged?
thanks
Junior User
Joined: Jan 2003
Posts: 79
Likes: 0
From: St. Louis
The dye you are using requires a U.V. light and is best looked for in the dark. Also if the pressures are the same the compressor is not running and off cycle pressures don't mean a thing to proper charge. It's all about the pressures and temps when the clutch is activated and the compressor is pumping.Also the possibility of a leak where you cant easily see it is high, often in the evaporator as they are made of aluminum and are subjected to high pressures in the off cycle and lots of vibration. To find these types of leaks you'll need to acess the evaporator ,but check all the easy to access spots thoughroughly first to rule them out.
Last edited by tinman67; Sep 6, 2004 at 02:57 PM.
