A/c pressure conformation.

[mgbrv8]

I just completely went through the AC system. I rebuilt my compressor I flushed all the lines, Replaced my condenser,Vacuumed it all down, Filled the system with 8 ounces of Ester Oil and 31 ounces of r134 because System originally had 36 ounces of r 12 And you use 85% of that in r 134. Now I put a picture of my gauges at a ambient outside temperature of 105F. And 75° at the air vent. Do these pressures seem reasonable?? Also does anyone know of any modification for our blower fan that can produce more pressure at the vent??

Dave
90 zr1

[SoCalZR1]

Hi Dave,

I am no expert but the pressure will also rely on the relative humidity, not just air temp. Looking at the performance specs in the shop manual these would be about right for R12 (so in the ball park) for 70% relative humidity at 100F and 2000 rpm. It states low side at 44 high side at 365 and vent temp at 75. Then again that's me working backwards and guessing your humidity. :-)

Mike

[mgbrv8]

Originally Posted by SoCalZR1

Hi Dave,

I am no expert but the pressure will also rely on the relative humidity, not just air temp. Looking at the performance specs in the shop manual these would be about right for R12 (so in the ball park) for 70% relative humidity at 100F and 2000 rpm. It states low side at 44 high side at 365 and vent temp at 75. Then again that's me working backwards and guessing your humidity. :-)

Mike

Im down here is the balmy southern tip of texas today was a sweaty 90% humidity. Im wondering if I could put a ounce or two more of r134 in there just to get a few more degs down at the vent.

Dave

[SoCalZR1]

Originally Posted by mgbrv8

Im down here is the balmy southern tip of texas today was a sweaty 90% humidity. Im wondering if I could put a ounce or two more of r134 in there just to get a few more degs down at the vent.

Dave

I am not so sure that would help Dave. At 80-90% humidity they don't even show anything for 100F. More is probably not better. I suspect you are doing good with 75f at that outside temp and humidity.

Again, no expert,but that is what the math seems to say. :-)

Mike

[White Bullet]

I am about to replace my evaporator and in my research I noticed that a number of evaporators were covered in all sorts of debris. Many stated that after cleaning them there was improved air flow and the vents. Just something to think about.

[-=Jeff=-]

at 100deg F those pressures look good:


Cleaning the Evaporator might help as well, just a job to get to.

Also if I recall right a differential of 40 deg from Ambient is the goal.. do you have this set on recirculate or not?

also was this measured while the car was sitting or moving? sitting in one spot make the AC work harder as you don't have as much flow across the condenser