Acura Repair Questions? Ask a Mechanic for Answers ASAP
I think what you have is low refrigerant issue with the ac system. When the system is undercharged the left side vents will blow warmer air than the right side. There could be a leak in the system which would cause this to happen.
it is possible it would be a blend door motor but unlikely. Sometimes if a blend door motor goes bad you can hear it ticking under the dash near the center.
If you do not hear any ticking I would have the ac system recharged since it is quick and easy to do as part of diagnosing this issue.