3 knob HVAC control upgrade
#31
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#33
Thread Starter
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It was suggested to me that the rear ac control could be replaced by this setup, and by using the Max AC mode to turn on the rear system at a preset fan speed. I have the circuit planned for this as either PWM fan control or simple set speed, but have not studied the factory harness diagrams yet for the rear AC. I should get a rear AC control in my hands to see how it connects to the harness.
#36
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About using a set speed on max AC for the rear AC...
The whole AC system is not capable of a solid "cooling" efficiency with both units in operation, so with max AC on, and then at a high fan speed enabling the rear will really pull down the cooling effect.
And..sometimes, I just run the rear AC because I dont want blown in the face a lot, or have a 4" cold middle arm..or...
I dont know about just enabling the rear AC at a set max/fan value.
I would consider..a simple on/off push button that turns on the rear AC on 'medium' fan independent of the front AC.
The whole AC system is not capable of a solid "cooling" efficiency with both units in operation, so with max AC on, and then at a high fan speed enabling the rear will really pull down the cooling effect.
And..sometimes, I just run the rear AC because I dont want blown in the face a lot, or have a 4" cold middle arm..or...
I dont know about just enabling the rear AC at a set max/fan value.
I would consider..a simple on/off push button that turns on the rear AC on 'medium' fan independent of the front AC.
#38
Thread Starter
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OK. Shouldn't be a problem as there are 2 unmarked detents split between the 2 right-most logos. One of these could be used for the rear air only control, while Max AC could run both at once.
#39
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Max AC is front recirculate, when you want peak cooling...opening the rear system automatically has a dramatic effect on front cooling if your goal is high fan, max-recirculate cooling.
#41
Race Car
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Well...I've consistently said that its a classic car and I'm good with the classic console...but I just sprung for the referenced controls off of ebay, anticipating a good outcome here..
:-)
Could you locate the factory A/C button somewhere and use that to initiate the rear A/C on demand? I'd actually be OK abandoning it, I think.
I wonder whether some of the issue could be from refilling refrigerant without the rear A/C activated?
:-)
Could you locate the factory A/C button somewhere and use that to initiate the rear A/C on demand? I'd actually be OK abandoning it, I think.
I wonder whether some of the issue could be from refilling refrigerant without the rear A/C activated?
#42
Rennlist Member
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Well...I've consistently said that its a classic car and I'm good with the classic console...but I just sprung for the referenced controls off of ebay, anticipating a good outcome here..
:-)
Could you locate the factory A/C button somewhere and use that to initiate the rear A/C on demand? I'd actually be OK abandoning it, I think.
I wonder whether some of the issue could be from refilling refrigerant without the rear A/C activated?
:-)
Could you locate the factory A/C button somewhere and use that to initiate the rear A/C on demand? I'd actually be OK abandoning it, I think.
I wonder whether some of the issue could be from refilling refrigerant without the rear A/C activated?
I dont have WSM here, procedure may be to turn both on, but either way you add the right amount, and thats that.
The issue is a lack of condenser volume/efficiency. But there is a way to spend a few thousand $ to solve it.
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Of if you have a 5spd, install the later model higher efficiency parallel flow condenser that the GTS has.
Last edited by Speedtoys; 09-08-2015 at 10:23 PM.
#43
Race Car
#44
Electron Wrangler
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