Jersey Jim
Member
CORRECTION: Mistakenly wrote "275" but high-side pressure at 2100 rpm is 375 PSI
In attempt to locate an A/C problem earlier in the week, which I soon after found to be a corroded A/C clutch-coil connector, I may have overcharged by adding a 12 oz, can of R134A. Here's what I measured just now on first hot day all week:
Ambient: 92F
High side/Low side equalized pressure: 108 PSI
Equalize time: 20 minutes after shutting off hot engine (75% in 10 minutes)
Engine Idling Pressures: 50/240 PSI
Engine raised to Highway speeds (2100 rpm): 30 psi/375 PSI
This 5.4L has rear A/C evaporator, and system capacity states 54 ounces R134A.
I witnessed no clutch cycling while Idling. All blowers on high, max cold, and all open windows.
I was by myself, so too noisy at 2100 rpm to hear clutch cycle. If it did, was prob from high-pressure switch.
Do these pressures look a little too high, or acceptable? I added Freon earlier in week when rainy and cooler, cuz low side was sucking down to 20 psi or below. I did not want it to cut out.
Also, does anyone know the pressure "opening" pressures for the low and high switches?
In attempt to locate an A/C problem earlier in the week, which I soon after found to be a corroded A/C clutch-coil connector, I may have overcharged by adding a 12 oz, can of R134A. Here's what I measured just now on first hot day all week:
Ambient: 92F
High side/Low side equalized pressure: 108 PSI
Equalize time: 20 minutes after shutting off hot engine (75% in 10 minutes)
Engine Idling Pressures: 50/240 PSI
Engine raised to Highway speeds (2100 rpm): 30 psi/375 PSI
This 5.4L has rear A/C evaporator, and system capacity states 54 ounces R134A.
I witnessed no clutch cycling while Idling. All blowers on high, max cold, and all open windows.
I was by myself, so too noisy at 2100 rpm to hear clutch cycle. If it did, was prob from high-pressure switch.
Do these pressures look a little too high, or acceptable? I added Freon earlier in week when rainy and cooler, cuz low side was sucking down to 20 psi or below. I did not want it to cut out.
Also, does anyone know the pressure "opening" pressures for the low and high switches?
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