[1995 Fleetwood Guy]

Happened yesterday the first time. AC blows nice and cold, but when I turned the temp up a little last night it just kept blowing ice cold through the vents. 52 degrees outside, maybe 65 in the car, but even with the control set at 85 I got ice cold air from the vents. When I changed it from 85 to 90 it blew nice and hot from the floor vents. Seems to be all or nothing, hot or cold, no in-between. I'm out here doing plugs and wires today, almost done. And since it's taking less time than I budgeted, I thought I'd look into this HVAC issue while I'm out here. What do the gurus around here think?

Thanks in advance for the help everyone!

 

[1995 Fleetwood Guy]

Ok, no takers...

Can anyone tell me where the interior temperature sensor is located, a photo would be great.

It's 44 degrees outside, if I put the automatic climate control on 85 it blows ice cold from the vents, if I put it on 90 it blows hot as hell from the floors?

I'm thinking it's the temperature sensor or the control unit, because everything else seems to be functioning correctly, just not doing it how I tell it to through the controls., and the compressor is definitely kicking on,

 

[csbuckn]

Can you hear any doors moving when you switch it around? HVAC is one of my least favorite subject with cars but I'm betting on the control unit. My decision is based on how many people here have replaced their display unit, though, nothing logical in my guess.

 

[1995 Fleetwood Guy]

Yeah, the doors seem to be moving like they are supposed to, it blows hot and cold when set at the extremes, and it blows them from the right ports. Just seems like either it's not sensing the interior temperature correctly, or not using that information to decide what to do. I'd really like to swap the control unit for a manual one off a roadmaster, but can't find one anywhere around here.

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I guess it'd help if I understood the system a little better too. Since I know it's creating heat, I wonder does the blend door control how hot or cold the air coming through the dash is. I can hear the door moving that redirects the air from the floor, to the dash and to the windshield, but is there another door that mixes hot and cold to adjust what's coming out?

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Also, saw another thread where someone with a 94 FL calibrated the temperature or something, he said it was in the owners manual, I can't find it, anyone have a clue on that?

 

[csbuckn]

So does the compressor stay running at all temps except 90?

 

[1995 Fleetwood Guy]

Yes and no. It appears to cycle on and off. I ordered a Roadmaster CCU from eBay, and a Delco blend door actuator from the rock, I can't find the interior temperature sensor available for purchase anywhere, but I'm thinking it's the CCU at this point. I'm hoping that with a known good blend door actuator, and the manual functions of the roadmaster unit, it'll act how I want. I have absolutely hated the automatic climate control since the day I bought the car, so maybe this headache is a blessing in disguise.

 

[1995 Fleetwood Guy]

Swapped control unit for the RM unit, way more control
Actuator was fine, temperature sensor was filthy with dust, pretty sure that's what was causing my headache.

Happy the annoyance finally pushed me to do the RM CCU swap, being able to blow heat from the floor and dash will be nice when winter comes.

I'd say thanks for the help, but it's been a pretty lonely thread. If anyone else has similar issues, or wants more info, PM me and I will be glad to share.