Mercedes-Benz Forum banner

81 - 100 of 173 Posts

·
Registered
Joined
·
301 Posts
Purchased arctic freeze refrigerant w/ die. When I attempted to add refrigerant I noticed that the gauge was already in the red, so I didn't add any. Here are my steps:

1. Added hose connection to can
2. turned car AC on to high
3. connected other end of hose to AC port

When I saw gauge in red I did not proceed. Does anyone know what this means?
I added a copy of the gauge in the image below.

http://www.troyldavis.com/e320/ac.jpg
 

·
Registered
Joined
·
35,776 Posts
THAT gauge at this moment shows the pressure of the can.
Just fill it up. The system is basically bulletproof - it has high pressure limit that will kill compressor if it goes too high.
 

·
Registered
Joined
·
301 Posts
ok. When I try to add refrigerant the needle goes to zero and doesn't move when pressing the trigger. I tried rechecking the system diagnostics again and the #7 changed from 4 to 5. There's still no change in the issue. I'm not sure where the compressor is and if it's even coming on when the AC is turned on.
 

·
Registered
Joined
·
35,776 Posts
Is it 0 like zero, or close to 0?
When you open the can valve, the car AC sucks the refrigerant in and with my manifold it drops to about 30 psi.
O would mean the can is slow, but eventually it should charge.
 

·
Registered
Joined
·
757 Posts
And you should be able to feel the weight of the can getting empty of fluid. Was the can getting cold? If so, it was charging.
 

·
Registered
Joined
·
301 Posts
I think it was close to zero. The can did appear lighter in weight,but I did not notice it getting colder. I did notice that when the trigger to release refrigerant was not pressed it seemed to go further in the "red" zone. When I saw this I stopped the process.
 

·
Registered
Joined
·
366 Posts
tdsilk - after replacing the seals on my compressor manifold I added three 12-oz cans of R134 to my SL (A6 compressor) and the air coming out of my AC is just a degree or two below the outside temperature. When the engine is not running my gauge reads 170psi and when the engine is running - 23 psi. My system does not have the overpressure switch so I am not sure if I should add more refrigerant, replace the compressor and/or replace the expansion valve.

ENGINE NOT RUNNING

ENGINE & COMPRESSOR RUNNING
 

·
Registered
Joined
·
35,776 Posts
The system should be charged with 1000g of refrigerant.
3 - 12 oz cans would be overfill. Likely the high pressure switch is pulsating AC not letting it run efficiently. Check the high pressure while driving.
 

·
Registered
Joined
·
366 Posts
Thanks Kajtek. Yes, 3 x 12 = 36 oz or 1,020 grams, which is 20 grams too much, though some systems call out for 39 oz of R134a, mine originally is a 49 oz capacity of R12, a conversion which I did about 15 years ago. Now wish I hadn't don't that. So, I've gone ahead and bled some of the pressure off to where my gauge shows 120 psi with the engine still and only 15 psi running. Air coming out is just as hot as going in (
 

·
Registered
Joined
·
35,776 Posts
With climatronic it takes just seconds and one finger to do full troubleshooting.
Why act without troubleshooting? Would you walk with scarf over your head?
Read sensors 1 to 8 on hot car, then observe #7 for couple of minutes.
Post results here.
 

·
Registered
Joined
·
366 Posts
Kajtek - what should the operating pressure be at the fill port on the older (Auto Climate Control III) R12 system converted to R134a?
 

·
Registered
Joined
·
366 Posts
Yes and no. Clutch closes. Compressor rotates. Even air gets a little cooler. But, no - I did not evacuate air using the vacuum pump. I should also state that I for the last 15 year I successfully ran R134a in this converted from R12 system. And 15 years ago, same as now, I did not use the vacuum to get rid of air before charging.
 

·
Registered
Joined
·
35,776 Posts
Evacuation is not for air removal, but for moisture removal, so charging without evacuation can be hit or miss.
Still without reading on both sides, we are in dark.
Do you feel pipes coming back from evaporator getting cold? Could be your heater valve stays open?
 

·
Registered
Joined
·
366 Posts
Right, moisture. I recently rebuilt my monovalve and it is working - i.e.: no hot/warm air when the system is on economy. It responds well to the temperature wheel and goes from cold to hot and back. Now, when I switch to AC or Bylevel I get air that's just a little cooler than ambient. And than it comes and goes, i.e.: it goes a little colder for a while (which still is significant here, in Mojave desert) to ambient temp, and than back to a little colder. I have a new dryer and expansion valve on order, just want to make sure it is not the compressor. Oh, and, yes, I do plan on evacuating the moisture before installing all that stuff this time.
 

·
Registered
Joined
·
35,776 Posts
If you have good compressor, the Venturi style vacuum pumps sell for $29 at Harbor Freight.
You might also move that topic into General or your model section as doing that under Climatronic title is probably stretching Raymond's patience. ;)
 

·
Registered
Joined
·
3 Posts
1999 E320 AC issues.

Hello, My first post. Been reading the thread, very helpful and informative, thanks to all who contribute here.

1999 E320 AC issues. http://www.benzworld.org/forums/images/smilies/crybaby2.gif

I've read the posts about resetting the codes, and then reading them again. They are as follows

E61-234 Sun Sensor B32
E61-235 Emission Sensor B31
E61-419 Electromagnetic Clutch A9K1
E61-459 Series Interface K2, Connection to instrument panel A1

1-85
2-76
3-87
4-91
5-84
6-80
7-02 14-17 Freon level normal
8-76
9-27
10-1.0
11-0.3
12-4.1

I don’t know what Emission Sensor the code refers to.
I understand the Sun Sensor is not critical to AC operation
I am mostly concerned about the Electromagnetic Clutch. I understand the Freon level is low and therefore will keep the AC compressor from working.

I evacuated, put ½ (6oz?) larger can with oil, dye, leak. The compressor turns by hand. I know I do not have enough Freon in currently and from this thread, I now know the correct range for #7, thanks!

I am hesitant to just add Freon without understanding the issues with the clutch. I will try to hotwire the clutch to see if it at least engages.

I believe I know the normal DIY gauges will not be valid and that I must use weight, but expecting the normal range from #7.

Can anyone answer what assumptions I have wrong and what my next steps would be for the AC?

Normal ranges for the codes would be appreciated and what the codes mean. Links to definitions?

Thank you in advance! http://www.benzworld.org/forums/images/smilies/bowdown.gif
 

·
Registered
Joined
·
35,776 Posts
Emission sensor is smog sensor. Located somewhere in windshield gutter will switch air circulation to charcoal filter when too much pollution detected.
Don't add Freon at all. Those cars use R134.
Can't figure what your "7-02 14-17 Freon level normal" means?
But start with clearing the codes and checking what will come back.
 
81 - 100 of 173 Posts
Top