AC Pressure High before filled to capacity

[GaryH]

The poster stated that when the AC was off, both balanced out at 110psi, which is what his photo demonstrates.

Yes, he added a new photo and edited the post after my post. See post #6.

 

[rashaunny]

What I'm seeing in your photo of the gauges is Low side: 110 High side: 110. Low side is way to high, high side is way too low.

When your vehicle’s air conditioning (AC) system behaves unusually, such as having high low-side pressure and low high-side pressure, several factors could be at play.

1. Defective Condenser Fan:
   • The condenser fan plays a crucial role in cooling the refrigerant. If it becomes damaged or blocked by debris, airflow through the condenser diminishes.
   • Reduced airflow leads to higher pressures on the low side, which can eventually cause damage, including evaporator coil leaks.
   • Solution: Inspect the condenser fan for damage or obstructions. If necessary, replace it.
2. Overcharged AC System:
   • An overcharged AC system can result in high pressures even when the engine is off.
   • Overcharging occurs due to excess refrigerant or an excessive amount of oil.
   • Solution: To resolve this, you’ll need to release some of the pressure. It’s best to have a mechanic handle this.

• If the low side pressure is too high and the high side pressure is too low, the compressor may be the culprit.
• Other components that could contribute to this issue include the dryer, expansion valve, or AC pressure switch.
• The dryer removes moisture from the refrigerant. If it fails, moisture remains, affecting pressure levels.
• The expansion valve can become clogged or defective, impacting refrigerant temperature and pressure.
• The AC pressure switch regulates refrigerant flow through the compressor. Sensor failures can cause imbalanced pressures.
• Solution: Inspect these components and address any issues accordingly.

Working quite well but but just curious how do you test Expansion valve I believe it is just a spring valve?

The pressure is not too bad, but the fact you didnt get to your rated capacity makes me think that you might have a condenser issue. It sounds like the refrigerant is not being cooled, causing pressure to be higher than they should.

Spray the condenser (in front of the radiator) with a hose gently and see if you get any temperature change at the vent with the AC running on max.

If you do you could have a poor airflow, or the condenser is clogged internally or externally.

Good idea that would be helpful either way

You’re still low on refrigerant, you state it took forever to fill. Engine at idle needs more airflow to keep condenser in normal range. Set AC to max, front and rear, keep idle up and charge by weight. Then can be diagnosed if there’s a problem

Good Point. When I filled it again at night at 79deg (Florida btw) it went so much easier.



Okay so update I filled again last night and checked for replies here. Florida 70 def. 10pm

Used the rest of my can but I may have put too much oil in it with the AC Pro and the s***** Walmart UV dye which I think also had will but it seems to be blowing very cold so I'm happy.

At night feeling was much easier and after the AC system ran on Max front and back for 10 minutes the low side which is the only one I was measuring this time went down to 30 PSI and even dipped to 29 PSI so I filled it and kept filling and it after the can was empty was still at 31 -33 PSI. Tried to measure temperature out event but turns out what I had was meet thermometer that bottomed out at 140 degrees so not much use lol

I think I used like 31 oz total of 33; but who knows really