Hello,
i recently had the cooling fluid from R12 to R134a changed (february) on my 94 b250 5.2. while i also had a vacuum leak (fixed now), the heat comes on at higher RPM. i took it to an "AC specialist" and they said the heater needs to be stopped as they are running at the same time (they couldn't do it and neither recommend anyone). the AC does cool, the condense water is dropping like crazy but the AC inside is not working and it's blowing hot air at ~30mph plus. any suggestions/hints?

 

Does it blow cold at lower RPM/idle?

 

It sounds like the blend door might not be going all the way over. As to the remark by the "AC specialist" that both are running at the same time, well that's just bunk. There is a heater control valve which stops the flow of coolant to the heater core only when the temperature is set all the way over to cool and the system is on Max AC. Other than that it's designed for both systems (heating/cooling) to run at the same time.

 

fairly. when they first switched to 134 it did (maybe also bc it was winter time (florida). but if you touch the cooling element (don't know the exact name) in the front it is freezing cold and condense water is all over the place. any idea? thank you....

 

i have it set on MAX and COOL. would you be able to hint me to the blend door? it sounds like this is something i can do myself, no? or you think the heater control valve is broken? can i do this myself (meaning without having to have all the 134 filling equipment, etc.)? thank you....

 

On my 2000 if I remove the glovebox the blend door actuator is right there. As you move the temperature **** up and down (engine running) you can see it move. There is a clip on it that once opened will allow for adjustment. But back in 94 I believe the blend door was controlled by a cable located under the hood on top of the heater box.

The arrow points to the cable in this image, #5 is the blend door itself.

 

Alloro, you are correct, the mode door is accessible from from under the hood. i moved it over to the "left" side with a screw driver and suddenly there is no more hot air. it does not seem to be moving when i move the lever inside the van but i want to double check that with a helper. maybe it's not moving over all the way. but either way, the hot air is no longer coming thanks to you and your help, i greatly appreciate it.

in the middle you can see mode door lever underneath the hood

 

Not to be picky but just to keep the terminology correct, that is the blend door lever, the blend door mixes hot and cold air to get the desired temperature out of the vents. The mode door (or doors) is what switches from floor to vent to defrost and everything in-between. In any case, I'm glad to hear your now getting cold air.

 

Alloro, thank you very much for the correction, proper terms is key. i apologize.