The Drier performs the same filtering function to your A/C system as the oil filter for your engine. Every time you exchange a major part of your A/C system you should do this easy job to make sure your A/C performs perfectly. In a T1N Sprinter the A/C drier is easily accessible and you should be able to replace the old unit with a new one in less than an hour. On the repair difficulty scale this is a three (1, easy to 10, hard).
This document describes how to replace the A/C Expansion Valve in a T1N Sprinter Van. The valve is located in the engine compartment under the windshield on the drivers side (for LHD Vans). The wiper mechanism is a bit in the way but with a wrench extension and an Allen bit this job is done in 30 minutes. On the difficulty scale (1 easy – 10 hard) I would rate this job as a 2.
If you’re like me and want to camp even when it’s blazing hot outside you’ll need an additional A/C unit to keep the temperatures down while stationary. This post describes how to install a rooftop A/C unit that runs on shore power. The job itself is not too difficult but requires cutting a whole in your roof and at least parts of the installation require the help of a second person. I would rate this a four on the 1 to 10 scale of difficulty.