Automotive Air Conditioning Information Forum (Archives)

char123 on Fri July 22, 2011 8:08 PM

Year: 1995
Make: Ford
Model: E150
Engine Size: 302
Refrigerant Type: 134a
Ambient Temp: 93
Pressure Low: 125
Pressure High: 0
Country of Origin: United States

I have the 95 ford e150 with the rear unit, from last summer to this summer, I ended up replacing the rear block expansion valve, I tied that in to the front system with new custom hoses, replaced condenser, accumulator, orfice tube, fs10 compressor/w clutch because clutch on old compressor wasn't cycling and it was freely turning, flushed both evaporators, front lines and pulled vacuum for at least 3 to 4 hours, held vac for hour, so I proceeded, with oil and 134a..... My static pressure is low 120 and high 0... yes I said zero!!, so I hooked up a set of r22 hoses and gauges just to see if the high side gauge was faulty on 134, but I got the same thing low 120 and high 0 at static, when I turned on van let idle 5 min, doors open front and rear blowers high, low side went to around 60 for a couple min then went to 50 -55 even at 1500 rpm, ambient at 92, but high side stayed at 0...accumulator and pipes were sweating, pipes were cold!, the compressor was not sweating, vent closest to evaporator gets to 62 degrees and rear 74, / I think the high side is really at 0! because when I detach the hoses I can tell the low side is under pressure but the high side is not! Problem... I think it should be able to get a little colder and I think the high side at 0 is a BIG PROBLEM and low side should be a little lower, helpful experience and knowledge would be very grateful!!!, I'm scratching my head trying to figure out why high is at zero!!! all the work that I did and careful steps before hand what did I miss!!!

Edited: Fri July 22, 2011 at 8:22 PM by char123

bromodragonfly on Fri July 22, 2011 8:26 PM

not possible. the system will eventually equalize when the AC is off.

even more not possible, considering your low side drops when the AC is on. The gas is being pumped somewhere.

Check your connection on the high side port. Maybe your quick coupler adapter is faulty. Some adapters have shutoff valves that need to be opened.

A quick test is to gently depress the schrader valve with a screwdriver or something (with AC not running), and see if any gas comes out.

-------------------------
There is no knowledge that is not power

char123 on Fri July 22, 2011 9:45 PM

thanks bromodragonfly, I pressed the valve on the quick connect high side and it worked! now my current readings are ambient 77, static= 90/90, at idle: doors open, front and rear fans on high 50/90, at 1500 rpm: 40/90, vent at evaporator 55 degrees, rear 74 degrees, I think there is a problem because i'm reading 90 on high, and my rear is at 74 degrees !