Poor AC at idle - have pressures/duct temps

[Gear Head]

hey all,

long time lurker, first post on the forum.
I'm having issues with my 07 F-150 and it's A/C performance. it's a CCoT system. I did an engine overhaul and replaced the compressor with ford OEM, new condenser, suction line, orifice tube and pressure/return lines along with a new accumulator. I replaced the evaporator in the dash about 8 months ago. Holds vacuum at 29.5-30inHG overnight so pretty damn leak tight.

i have a manifold set, at 65 deg ambient, engine idle 675rpm i get this:
Low Side: 30psi
High Side: 225-250psi
Duct temp: 50 deg F

the temps eventually get cold after driving for about 15-20 mins but creep up again if coming back to stop/go traffic.
i think that the high side is too high and the low side isn't low enough which is why i get poor duct temps.

What do i look at first?

[tbirdtbird]

1. valid test of system not possible below 80F ambient
2. pressure readings s/b at 1500 rpm/max fan/max cold/doors open / recirculate (ie full load test). Then report back the numbers.
3. your low is actually about right. The high we would like to see lower. Condenser fan working properly?
4. *No* car AC will perform well at idle, the compressor is not able to do much work at idle speed. That is why we spec 1500 RPM

[Tim]

Make sure the fan clutch is working correctly. Mist the condenser and see if temps drop. Having the correct refrigerant charge in the system is a must.