Air Conditioning Help?

[Data804]

(1994 Ford Explorer XLT).I have put R-134 Frion back in the air compressor but the can went empty a little too fast. I noticed that there is another R-134 top on the right side of the truck. Are there two places in the engine that you have to put R-134 into?

 

[mowermechanic]

There is a High pressure and Low pressure port. Those are usually the only 2. You want to add it to the low pressure port. The one that's in between the a/c pump and the condenser. You use the low pressure port. When you add the refrigerant, you are supposed to shake well, and change canister angle from the 12 o clock position to the 3 o clock position every 3 seconds....

 

[Cobraguy]

WAIT!! I don't have a gen 1 to look at, but I believe that is wrong! The low side port is on the accumulator...not between the compressor and condensor. That is the high side port! That's the way it is on the gen II's. Do NOT attempt to charge through the high side port for any reason. That side can reach pressures to 300 lbs...and higher. What happens to that little can of freon when it's exposed to that kind of pressure? I don't know what it's burst rating is, but I sure don't want to find out that way.

Where the low side port dumps into the accumulator first, you are safe to charge with the can upside down (liquid). It will charge much quicker.

 

[Data804]

This is all greek to me but does it go on the left side of the truck or the right side. Both tubes have on them R-134 Frion. (1994 Ford Explorer)

 

[Blacksheep Josh]

There should be a H or L on the tops. Use the L (low pressure) side to charge it...

I cant' remember currently which side that's on, but if you aren't sure, have a shop charge it.

 

[ErnieX]

The ports on the A/C lines should be different sizes. If you're using just the short hose you can buy to attach to the can and charge, it will only fit on the low side fitting.

 

[Cobraguy]

Ernie is correct. But if you're using gauges, the low side port (the one you want to charge through) will be next to the evap case on the right side (passenger) by a tank looking affair that is...what...three or four inches in diameter and about 10 inches tall. That's called an accumulator. If you're still not sure, look up accumulator on an online parts store and look at the picture.

I don't want to sound rude...and I hope you don't take it that way...but if you are struggling with what port is what, you really shouldn't be attempting this. You should have someone familiar with a/c look at it. This is something that if done wrong, can cause damage to your car. And you too in some cases.

 

[Data804]

I dont take that the wrong way at all cobra. I put the Frion in the low port which is located near the passenger side of the car. I was just wondering what the other one is for which i know now is the high port near the drivers side. Another question i have is at what point and what do you put in the High pressure port?

 

[Cobraguy]

Nothing should ever go in the high side port. It is used to connect a gauge to read pressures so you can see what is happening there. You can use that port to evacuate the system. Some use it to install freon after initial evacuation, then close it and use the low side port. This is NOT a good practice and I've never seen it taught. It's too easy to start the car and forget to close the high side valve.

EDIT: There are charging machines out there that charge through both ports simultaneously. However, these machines charge without the vehicle running by heating the freon bottle...and in some cases, actually pumping it. At no time is the bottle subjected to high side operating pressures.

 

[Data804]

Alright. Thanks for the help.