Hot air

[old911doc]

After finding fragments of foam blowing out of my vents, I removed the heater box (no small task!) to repair the metal 'doors' inside. I laid a layer of fiberglass on each side of each door, and after it cured trimmed it to the edges of the metal. After the dash was reassembled and the A/C vacuumed and filled and coolant refilled, now I only get heated air out of all the vents, at any settings on the A/C controller. When the A/C is set on max cooling, the air exiting the ducts is 125 F when the ambient temperature is 80F.
Scanning with Durametric revealed no 'codes' in the A/C system. Interestingly, during the test cycle as Durametric controls the various stepper motors, there is cold air out the ducts for a fleeting moment, about 20 seconds, before the outflowing air becomes hot again. The refrigerant pressures are 38 psi low side, 250 psi high side. When I look under the heater box, the two stepper motors I can see move with commands, and their plastic pushrods are connected. The recirculation door moves normally. All the wires I can see appear in solid connection.
Any suggestions what might be the cause of only heated air from the A/C system, before I take the whole thing apart down to the firewall again?

[PaulE]

Originally Posted by old911doc

After finding fragments of foam blowing out of my vents, I removed the heater box (no small task!) to repair the metal 'doors' inside. I laid a layer of fiberglass on each side of each door, and after it cured trimmed it to the edges of the metal. After the dash was reassembled and the A/C vacuumed and filled and coolant refilled, now I only get heated air out of all the vents, at any settings on the A/C controller. When the A/C is set on max cooling, the air exiting the ducts is 125 F when the ambient temperature is 80F.
Scanning with Durametric revealed no 'codes' in the A/C system. Interestingly, during the test cycle as Durametric controls the various stepper motors, there is cold air out the ducts for a fleeting moment, about 20 seconds, before the outflowing air becomes hot again. The refrigerant pressures are 38 psi low side, 250 psi high side. When I look under the heater box, the two stepper motors I can see move with commands, and their plastic pushrods are connected. The recirculation door moves normally. All the wires I can see appear in solid connection.
Any suggestions what might be the cause of only heated air from the A/C system, before I take the whole thing apart down to the firewall again?

Could you have crossed a wiring connection somewhere? The reason I ask is that in my car, when I turn on the front windshield defroster button, rather than just use the top of the 3 buttons that direct airflow to the windscreen, dash vents and floor heater, the air temperature goes from its set value to full hot. So I'm wondering if when you put everything back together, something got switched around which is why you only get hot air. Note I am not a technician and don't play on tv, so my suggestion may be totally off the wall. Maybe you could turn the temp all the way down to low and hit the front windshield defroster button and see if that results in cold air.