"Tricking" the AC system to blow out 60 degrees?

[AZ94Q]

I saw Q45tech mention you can "trick" your AC to blow out at 60, as opposed to 65. This happens, even though the display still reads 65.

I just looked over the service manual, but didn't seem to find it.

Can someone provide some insight on this?

[Q451990]

If you have the 1994 FSM check HA-49.

Heath

[AZ94Q]

I have the 92, but perhaps that number will help.

[AZ94Q]

I can't seem to locate it.

Would you please describe it?

[Q45tech]

Page HA 64 in 1992 FSM.

Understand that trimming the display won't change the residual temperature other than delaying the point when the air mix door starts inserting some heat into the air flow.How the ecu reacts when the center vent temp starts to approach 47-48F.

[AZ94Q]

Thank you q45tech!

first time I check out the FSM... tons of interesting info...

I never knew the hvac syste had a sunload sensor

[911/Q45]

If you set the temp to the minimum(65°), doesn't it just blow max cold without regard to the interior temp?

[wamQ45]

If you set the temp to the minimum(65°), doesn't it just blow max cold without regard to the interior temp?

Seems like that's what mine does...just ask my wife's.....never mind...

[elwesso]

LOL at wam!

I think 65 is max cold, as the context clues in the FSM seem to dictate it to me. The only thing trimming it down to 60 would make the fan stay on longer.

[Jesda]

Chryslers have a mode where you can turn the temp knob all the way down to 60, and it will be in "Max AC" mode (coldest, full fan) until you set it back to 65, where its automatic again.

-Jesda

[Q45tech]

The compressor stays on and self regulates the volume to maintain correct suction pressure and the automatic function just adds heats via the mix door [which can be closed [zero] to up to 54.5 degrees open].

Obviously the vent temp will be a function of input [return] temp and fan speed [realize that from 5 to 10.5 volts is almost infinitely variable increments [12-13 speed steps] of fan speed ] and high is a fixed 12 volts to the fan motor. Sunload compensates by varying the blower speed.

The lowest normal high speed fan center vent temperature is 46F with a 77F inlet temperature [& 60% RH] at 1500 rpm after more than 10 minutes in shade no sun load.

As you near the set temperature the fan will slow down and the temperature will drop before the heat door opens slightly to maintain something in the 46-55F vent temperature. Which depending on sunload should be able to maintain a 70F inside with reasonable fan speed at 90F outside. Each normal weight human inside adds 3-4% [each] to the cool down time

[qship96]

q45tech,thanks for the ac info,based on your parameters,the 96q is operating to spec! hope it continues!