What is the reason for blower on low? Most AC sites recommend blower on high and system in recirculate mode, windows down, doors closed so you can reach in easily to feel the vents.

Below copied from Troubleshooting with Gauges FAQ

"Should I test with doors open or closed, high idle, blower on high or low?
We should measure high and low side pressure at stable engine speeds. This can be done at engine speeds just slightly above idle. 1,200 to 1,500 RPM is most often recommended. On front wheel drive cars, never rev the engine or hold the engine at high RPM while charging or checking pressures. This can create dangerous high pressure. This is because electric condenser fans are fixed in speed, and will not compensate for high engine RPM. The same holds true on rear wheel drive cars with engine driven fans. A defective fan clutch could cause pressures to reach dangerous levels at higher engine RPM.
We like to test with the system in MAX position on high blower with doors closed. Windows can be open. MAX (recirculate) mode is preferred since we'll need to have the hood up while charging and testing. In fresh air mode, hot engine heat can be drawn into the fresh air cowl under the wiper blades. Same reason we would like to test with doors closed. We would like to keep engine and exhaust heat from causing abnormal heat load on the evaporator. We're not bothered by having the windows down, since this helps create a typical and stable heat load. And it's easy to reach in and feel how cold the vent temps are getting.
Testing should be done with blower speed on high. Low blower speed will reduce heat load on the evaporator to the point where compressor cycling can occur. We want nice stable conditions when testing. When needed, low blower speed can be used to force low side pressure down during testing and adjustment of compressor cut-out pressure."

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85 300D turbo pristine w 157k when purchased 161K now
83 300 D turbo 297K runs great. SOLD!
83 240D 4 spd manual- parted out then junked

Draining means taking compressor out to remove drain bolt, flushing all hoses, condenser and evaporator, i.e. starting from scratch.

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85 300D turbo pristine w 157k when purchased 161K now
83 300 D turbo 297K runs great. SOLD!
83 240D 4 spd manual- parted out then junked

Don't worry about it. Your system is fine and cooling OK. If you are happy then just enjoy. There is no way to tell how much is in there, so there is no way to know how much to remove. A little oil over the top is not going to hurt unless you fill the system with oil completely. Oil will be pumped around the system with the Freon or R134a, so will be distributed around evap, condenser, rec/drier etc. A/C is not Rocket Science and please please do not let someone to make you believe it is.

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Not MBZ nor A/C trained professional but a die-hard DIY and green engineer. Use the info at your own peril. Picked up 2 Infractions because of disagreements. NOW reversed.

W124 Keyless remote, PM for details. http://www.peachparts.com/shopforum/mercedes-used-parts-sale-wanted/334620-fs-w124-chasis-keyless-remote-%2450-shipped.html

1 X 2006 CDI
1 x 87 300SDL
1 x 87 300D
1 x 87 300TDT wagon
1 x 83 300D
1 x 84 190D ( 5 sp ) - All R134 converted + keyless entry.

+1

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CENSORED due to not family friendly words

dhake2,

Can you put your gauge set on again to read the static pressure?

Below copied from Troubleshooting with Gauges FAQ


Can I tell if the system is full with a static pressure reading?
No. We might determine if there is liquid refrigerant in the system, but we won't be able to tell how much liquid it contains. For example, a thirty pound can of refrigerant will show the same pressure whether it has thirty pounds in it or if it only has 1 ounce. With static pressure, you will only know if the system has some amount of liquid refrigerant present.

What good is a static pressure reading then?
With our initial pressure reading, we can tell if the system has enough pressure to satisfy the low pressure switch and enable the compressor to operate. Static pressure is used to determine if a jug of refrigerant is contaminated with air. Static pressure can also be used to determine if a system has enough pressure to begin leak testing. Your static pressure should be no lower than 50 psi when leak testing.

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85 300D turbo pristine w 157k when purchased 161K now
83 300 D turbo 297K runs great. SOLD!
83 240D 4 spd manual- parted out then junked

To determine how close to freezing your system is able to get... also in checking the setting of the TXvalve.... you put the blower on LOW so that the air is in contact with the evaporator the maximum amount of time.. as compared to being on a higher setting... if , under good test conditions, it will not get close to freezing you know to keep working on finding the problem..
When you see people quoting 36, 38 degrees.. those are not with the blower on high..... . it has to be on low...

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1980 240d ,

chain elongation, cam marks reference:
http://www.peachparts.com/shopforum/diesel-discussion/10414-help-i-need-check-stretch.html

http://www.peachparts.com/shopforum/diesel-discussion/305365-9-degrees-chain-stretch.html

evap fin cleaning:

http://www.peachparts.com/shopforum/diesel-discussion/156207-photo-step-step-post-showing-w123-evaporator-removal-1983-240d-1982-300td.html?highlight=evaporator

A/C thread

http://www.peachparts.com/shopforum/diesel-discussion/297462-c-recommendations-mb-vehicles.html