Good old Bill

I have trouble with the diagram so can't help there. Find the compressor and note the two lines. One is larger than the other. The larger is the suction side, follow it to the service port. The smaller is the high pressure and again follow it to the high service port. With using the small cans, use the low pressure side for adding freon. Good luck. Welcome to the site, as you get more familiar with the site, start a new topic for faster results, sometimes highjacking onto an old thread gets overlooked.

johny1

I added Freon to my ford myself. I used the kits sold in the store that have a gauge. I hooked up the hose to the valve which is located on the side of something that looks like an aluminum cylinder. The valve has a black cap on it and I think the hose only fits on that valve.

gibby777

I recently talked to an A/C tech and he said that if you have to replace freon that you have a leak somewhere, that stuff doesnt just disappear. This really is a job better suited for a professional. Take it to an A/C shop, not the dealer, they are considerably more expensive

Vincent Martinez

What is #2?

Kdawg_69

that would be the high pressure port but like everyone else has said take it somewhere to get it done right

Vincent Martinez

So let's say I let the air out of that joint...what do I do to fix my stupidity?

TomB275

Except for this year's newest systems on some cars, all A/C systems leak slowly depending on frequency of use. Refrigerant molecules are very tiny and escape even in good systems. Needing a can every 3-4 years is not a big deal.

A couple of things first: the A/C system uses refrigerant. Freon (generically Refrigerant 12 or R12) was a brand of R12 from Dupont and R12 was quasi-banned (highly restricted) many years ago due to ozone layer concerns. Your F150 uses R134a which is now soon to be banned (highly restricted) as well because it has a high greenhouse gas effect.

You can safely add refrigerant to your system as long as you wear eye protection (goggles) since an accidental spritz of refrigerant in your eye can freeze the eye on contact and cause blindness. Also, never connect a can of refrigerant to the high side (high pressure) port (2 in the schematic) when the compressor is operating. The high side pressure could explode the can. Your recharge kit has a fitting that will only fit the low side port 5 so these kits are designed to avoid problems. The high side port 2 is too large for the kit provided connector. The high side port is for attaching a high side measuring gauge.

To use a recharge kit with gauge for R134a:
1 Verify that your vehicle takes R134a via label under the hood. Old vehicles use R12 and you can't mix the 2.
2 You need a pan of warm water.
3 Make sure the puncture pin is fully backed out and the threaded fitting is not protruding. Turn the valve for the pin counterclockwise until it stops.
3 Put on your goggles.
4 Attach the can of R134a refrigerant to the gauge line. Then screw in the fitting so it seals on the can.
5 Remove cap from A/C low side port and connect gauge. It snaps on. If it doesn't snap on it is probably the wrong port.
6 Start engine and read the gauge. If about 40 psi (unlikely) you have a full charge . Make sure compressor is running. System in defrost will always ask the A/C to run.
7 If less that 40 psi you can recharge it. If above 40 psi WITH compressor running you have too much refrigerant or an A/C problem.
8 Once you puncture the refrigerant can you can't reseal it or save it.
9 With the compressor running, the can upright, and the fitting tightly sealing the can, slowly screw in the pin to puncture the can.
10 Slowly unscrew the pin until refrigerant flows then stop and wait. The can will get very cold as the refrigerant flows out.
11 Screw the pin in and out to modulate the gas flow. Keep the can upright so only refrigerant gas flows out. Turning the can upside down will release liquid that could slug the compressor and damage it.
12 Eventually the refrigerant flow from the can will slow or stop, so dunk the UPRIGHT can in the warm water. This will keep the gas flowing. Make sure to unscrew the pin to open the flow but don't loosen the seal of the fitting on the top of the can.
13 You may need more than 1 can to fully recharge.
14 to disconnect the system, screw the pin fully in, then disconnect from the low side port. Then unscrew the pin slowly to release any remaining refrigerant in the can.

Follow the recharge kit's directions. The gauge will have a guide for a full charge but 40 to 45 is a reasonable full charge. Overcharging will reduce cooling not increase it.

If your system was empty due to a big leak (cut hose etc.) the system will have moisture in it so it needs the receiver/dryer replaced and the system evacuated to remove all moisture, then a full recharge. Moisture in the system will cause very erratic operation as it freezes and blocks refrigerant flow. Receiver/dryers have a water absorber (dessicant) inside but get loaded to capacity if the system is opened.

carscome1st

I'm fairly positive that the low pressure side(suction) is the smaller of the two fittings. The high side is larger so you cant hook up a standard recharge hose to it without forcing it.
On my truck, 99 f150 5.4l, the low side is on the side of the accumulator(filter/drier).