Hey y'all, I'm new to the thread but have been lurking for the past 2.5 weeks. I picked up a really clean almost rust free (1 spot on the trunk seal) 190e and have been doing a ton of work on it to procrastinate my studies (mechanical engineering major and jk on procrastinating but my time has been split). I've worked through a lot of the basic maintenance stuff I needed to do like changing all of my fluids, changing out the worn k1 spring in my transmission, replacing all filters, etc. I'm loving this car to say the least and giving it the attention it deserves. The next big problem at hand is my air conditioning system and it's staying one step ahead of me. Heres the list of things that have been checked and the problems that are persisting:
Things checked:
- I have some pressure in the ac lines, not sure how much though as I just poked the valve in the line
- I checked the relays and fuses and they're good to go.
- A buddy of my (electrical engineering major) re-soldered some questionable solders on the climate board
Problems
- I have warm air coming out of the side vents but outside temp air through the center vents (I read that the center vents are not connected to the heater core so it makes sense for the inner vents to not be as hot)
- The temperature dial makes no change to the air temp coming from either set of vents
- Nothing happens when I press the different mode buttons (high, high/low, low) which is probably a blend door problem so I believe I have to pull the dash
- The compressor does not kick on when I press the AC button
- The system has been converted to R134a I believe

What else should I check before pulling the dash? Does the problem sound like it could be just needing to get to the mono valve and giving it a recharge? I want to know the alternatives to pulling the dash because that means the car will be in pieces for over a week since I'll have to take it apart to figure out what to order, then wait on it to arrive and do the install and reassembly. Thats a lot of time for my car to occupy my buddy's garage. Any help is appreciated.