Hi! The A/C in my odyssey isn't cooling the driver's side in front at all. It cools the front passenger side okay, and the back passengers a bit. But the front driver side doesn't cool at all below ambient air temperature.
The clutch definitely engages, the condenser and evaporator fans are busy working. The belt seems in good condition and isn't squealing. And the high and low refrigerant line pressures are close to nominal.
I removed the trim panel to the right of the gas pedal. I confirmed that driver's side blender door works and is actuating. It is also audible—low squeaks as it changes position.
When I set driver-side temperature to "hi", the bender door switches to one position, and the air coming out the vent gets hot. When I switch it to any cooler temperature (it is a hot day today, so I think the temperature could measure over 86°F), the blender door moves to the opposite position, and the air coming out the drivers side vents cools down to the ambient temperature. Meanwhile, the passenger's side vents are blowing cold.
As the interior temperature of the car cooled – probably below 86° – the blender door did not switch back to "hot." It just continued to blow ambient air.
Could it be the control unit? It can tell it's hot out, and the blender door actuates, so I'm naively guessing that's not the problem.
Is there an obstruction between the evaporator core and the driver-side blender door? That's what makes sense to me, but I'm new at this.
My Haynes manual has nothing on this.
Any ideas?

 

get the real manual. it will pay for itself and probably still be worth this much when you get rid of the van.

I have found some of these factory service manuals at our local library too, so that's worth checking on.

I have read that some blend door actuators can slip on the pivot preventing the door from moving fully to one end or the other. But I think your blockage theory is worth investigation too. I recently replaced a mode actuator in a friend's CR-V and found rodent activity around the duct work and on the inlet side of the cabin filter. there was nothing inside the ducts, but the potential for it was there.

 

Hi @hondamark35 , thanks for that tip the other day. I got the real manual, and *wow*. So much great stuff in there!
Knowing how the air flow is channeled in the climate control unit made all the difference debugging the thing. I peered in using an IR camera: only some of the surface area of the evaporator core was cooling down – coincidentally, that part was on the passenger side. I know there was some air in the system (don't ask), which makes a poor refrigerant. So I'm guessing an air pocket in the evaporator core was keeping things from working well even after I'd topped it off and the pressure gauge readings were...not terrible.
I had it evacuated (and recharged) at a shop, and both sides now blow icy cool.
Thanks, @hondamark35 ! Now I only wish the four-volume manual for my camry were that cheap!

 

glad it worked out!

yes, there are some others I'd like to add to the library but the prices are eye-watering sometimes.