what's your a/c evap temps?
06-15-2015, 05:40 PM
#1
Member
Thread Starter
what's your a/c evap temps?
Ok crew...
I am in hot/dry Arizona. I had my compressor replaced last year, but I am still having issues.
Running pressure is about 12-15bar when driving at 100 degrees ambient, evap temp is 57-60 degrees. I checked static pressure today before I started the car, It was 8 bar at 95*. That seems about 1 bar high (15-20psi).
So I think given my pressures across the board seem high, I am going to bleed some 134a and see what happens.
I am wondering though if the compressor I had installed last summer had a full oil charge and the system now has too much oil and not enough juice.
So can someone here in the desert who is about 100* ambient let me know what numbers 5 & 7 are on their climate diagnostic?
I am in hot/dry Arizona. I had my compressor replaced last year, but I am still having issues.
Running pressure is about 12-15bar when driving at 100 degrees ambient, evap temp is 57-60 degrees. I checked static pressure today before I started the car, It was 8 bar at 95*. That seems about 1 bar high (15-20psi).
So I think given my pressures across the board seem high, I am going to bleed some 134a and see what happens.
I am wondering though if the compressor I had installed last summer had a full oil charge and the system now has too much oil and not enough juice.
So can someone here in the desert who is about 100* ambient let me know what numbers 5 & 7 are on their climate diagnostic?
06-15-2015, 10:20 PM
#2
MBWorld Fanatic!
I can give you exact numbers when I fly back to So Cal late in the week, but your evap temps are very high. The vent temps will be cooler than the evap sensor because the air passes over the entire evaporator, but 60 is way too high. You want the evap sensor in the 30's. It has to be above freezing, but within 10 degrees. Also, for the R134 barometric / #7, I get you want the number at 100 degrees or higher, but at what engine speed? 500/idle? 1500/city cruise? 2000/freeway cruise? What RPM?
06-16-2015, 11:49 AM
#3
Member
Thread Starter
I can give you exact numbers when I fly back to So Cal late in the week, but your evap temps are very high. The vent temps will be cooler than the evap sensor because the air passes over the entire evaporator, but 60 is way too high. You want the evap sensor in the 30's. It has to be above freezing, but within 10 degrees. Also, for the R134 barometric / #7, I get you want the number at 100 degrees or higher, but at what engine speed? 500/idle? 1500/city cruise? 2000/freeway cruise? What RPM?
06-18-2015, 02:07 AM
#4
Member
Thread Starter
I purged all the 134a in the system and vaccumed down to -25. I added 36oz of 134a.
Still driving down the road 1500rpm, 90* ambient, I am pulling 53* at the evaporator (#3,4,5 identical) However, I think again I overcharged. I think the sticker on the car says 1.9lb which would be 30-31oz.
I can bleed a little off, but I doubt It would make much difference.
Still driving down the road 1500rpm, 90* ambient, I am pulling 53* at the evaporator (#3,4,5 identical) However, I think again I overcharged. I think the sticker on the car says 1.9lb which would be 30-31oz.
I can bleed a little off, but I doubt It would make much difference.
06-22-2015, 01:20 AM
#6
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Join Date: May 2004
Location: St Louis, MO
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2000 CLK430, 2012 BMW X5 3.5d
Your evap temps are way too high. Mine - (CLK430 2000 with 87K) Ambient around 92F with super high humidity (today my outside windows fogged up with the ac on). My #5 (evap) reading at idle after about 5-10 minutes with fan manual set at 4 bars is between 37F and 39F. Generally it will settle at 38F even with super hot temps and at idle for long periods (30mins or more) - St Louis summers 105F. During normal driving it will hover around 39/40. The number 7 reading - normal driving stays at about 12-14 but can vary wildly depending on driving speed, etc. 86K miles with original compressor - condenser replaced several years ago-
Supposedly have a small leak - as determined last year when I had it prof charged at the pipe from the condenser to the dryer. Was charged last May - super hot summer and its now June - still get into the 37-38 range. If it was leaking it would have gassed out in a year surely. What I do notice is during normal driving around town it takes a little longer to get there and there seems to be some weird hiccup where it feels like the temps swing up then back down - don't know - may have to have it rechecked.
Supposedly have a small leak - as determined last year when I had it prof charged at the pipe from the condenser to the dryer. Was charged last May - super hot summer and its now June - still get into the 37-38 range. If it was leaking it would have gassed out in a year surely. What I do notice is during normal driving around town it takes a little longer to get there and there seems to be some weird hiccup where it feels like the temps swing up then back down - don't know - may have to have it rechecked.
Last edited by stim141; 06-22-2015 at 01:24 AM.
06-23-2015, 03:00 PM
#7
Member
Thread Starter
Yea, when I changed the compressor I kept the same evap and condenser and they didn't flush it. I'm thinking that I either have a gummed up condenser or there is a small clog in the expan valve or a partially clogged screen at the compressor. My low side pressures will not drop below 38psi. even with proper charge.
