Claprood - I was going to welcome you to the CAC, then I noticed you joined last May, so instead, I'll say congrats on your first post!
To expand on troubleshooting info:
is any air - hot or cold - coming out of the passenger side vents? No air at all?
This will give readers of your thread more of an idea what is - or what is not - happening.
I experienced an issue with my '98 last year in which the driver's side was blowing COLD air while the passenger side was blowing HOT air. I was advised to disconnect my battery for a few minutes to reset an actuator but unfortunately that didn't help. When my mechanic replaced it we found a cracked gear in the actuator.
Post answers to the questions I mentioned and someone should be along shortly with more extensive mechanical knowledge than me.