99jz71

ok lets start that im pretty handy with working on my vehicles. so my problem is again my ac in my 99 burban. front is not as cold as rear again!!! please help wife nagging that its hot and i should have let it go and bought a new one, but couldnt cuz its paid for and never has giving my any major issues until now. DONT WANT TO BUY NEW BURB HELP!!!!!!

new parts;
compressor
accumalator
orfice
condensor
rear evap
rear exspansion
all in the past yr right b4 winter..

during the first of spring it was stolen.. recovered it replaced all parts took about 8months mostly interior crap.. finally replaced everything. went to use a/c and was not cooling. found out that the orfice was partly pluged. replaced vaccumed refilled with 134a.
low side 45ish high side 200ish ambeint 86ish at night. front ac blows around 65degrees and the rear is around 45degrees. did reserch about blend door and mine is diverting from top, bottom, and both. also the diverter for the fresh air is working. my accumalator is not condensing [sweating], nor is the lil inline filter on the low side on top of the compressor. the line with the inline orfice is condesing [sweating] b4 the orfice not after. took the plastics apart under dash to get an acurate temp of the evaporator and its around 60 degrees. its condesing but not much and of course its not cold either. i have a huge headache over this (wife) and also fustrated myself...

99jz71

wow 47 views and nobody has or had this problem, or any info?????

RacerX

1. what about the front evap?
2. how much gas did u put in? it takes like 3.5lbs I believe.
3. does the Climate Control Panel work? Do you hear the blend doors move?

RacerX

ok, i missed some info in ur paragraph. I think you didnt put enough gas in. The rear has its own reservior and is ALWAYS ON RECIRCULATE. Thats why it is colder. I say another can in the front. The line from the accumulator to evap should be sweating some. The evap should be at like 45 degrees. In your case it is not even draining from the front.

99jz71

its drainin from the front but,minimal..and no sweatin is goin on under the hood except near the orfice tube.. i calculated the ambeint to the pressure/ temps and i think i am at max refridgerant level (i am using a 30lb drum of 134a not cans) ..thats 2.2 to 2.5 X's the ambeint...for the high side... heres my brain fart if the accumalator is clogged does that effect both front and rear or just front.. if i had a detailed diagram on how the dual air worx and what controls what, with pix ,wow that would be so much easier for me.. i do HVAC for a living but for some reason this here is kickin me bad... if any body knows were i can get that info or knows what and how, that would be greatlly appreciated....

99jz71

lbs? dunno how many i went by pressure and temps. no scale to weight it in.. using 30lb drum.
front evap is oe..
yes the ac control panel worx.. on all settings even heat and defrost etc..
i SEE the doors move or open close..i took it apart to look

RacerX

the capacity should be on the accumulator or radiator shroud. there is another accumulaTOR for the rear. The rear is always on recirc. the front is the only one that can adjust flow.
Well I never used pressures to charge even when I did it from a bulk can like you. Those RobinAir machines also charge by weight. But I do believe if your evapr is 60 then the refrig. level is too low.

In the OLD Ford manuals(from the 70s) they used to tell you to count compressor cycling times to determine charge level.


My Burb is a 93, and I had a problem like you last month. It was cold in the rear but warm in the front. It had factory R-12. I converted to R-12a but used Quest R134a fittings. The low side fitting kept the Schrader open so it would slowly leak out. I just topped it up with another can and when I was through I removed the low side adapter from the accumulator so there was nothing keeping the Schrader open.

no leaks in the front no?