OK, most of the time it's not an issue, but last year while in AZ and NM, the front dash A/C and the rear 12V A/C system (not Starcool or any of those variants), could not keep up with the heat. Admittedly, the red paint and many windows didn't help the situation. Last time I was at SMBw, I had them check the refrigerant and I was told it was OK. All window excepts the windshield and drivers and passenger doors are tinted. I plan on eventualy tinting the door windows too.
I have two thoughts about possible improving the A/C situation that I want to bounce off people. I know not many people have the rear 12V A/C system, but here goes.
1) Insulate the refrigerant lines that go front the front sytem to the rear system. I'm not sure I have it completly correct, but the two systems are coupled, sharing refrigerant. The lines between the two I don't believe are insulated. Does anyone have recommendations on what sort of insulator I should use?
2) Found this item discussed on another board. Sounds like an easy install, except nothing is easy to install in a van, so I need to make sure I install it in the right place. If I'm not comfortable doing it, I may have SMB install one next time I'm up there. At least on my van, even on Vent, the air is quite warm, and this may explain why.
"In a 2003-2006 Superduty(6.0L Powerstroke) hot engine coolant is flowing through the heater core whenever the heat or Air Conditioning is turned on. The system does not differentiate between the two. This is fine when you are running your heater. However, running the Air Conditioner is a different story. When your AC is on, your cold air is not only flowing across the evaportator coil but it also flows past the heater coil which has hot engine coolant flowing through it. Even with the air flow diverted around the heater core, the heater is still emitting heat just like a radiator. This results in a very inefficient air conditioning system in these vehicles.
This DIESELSITE Air Conditioning Control Valve will automatically shut off coolant flow through the heater core when MAX AC selected. The result is a decrease in duct temperature by 10 degrees or more which will be felt through your vent openings into the cab. This gets COLD!
Install takes about 15 minutes and requires no special tools. Everything you need is included in the kit. Full detailed instructions including color pictures are included."
http://www.dieselsite.com/index.asp?Pag ... ProdID=473
Herb