640i Low Pressure AC Port

[xidamaaa]

Hi all,

Can anyone who’s done ac recharge confirm the low pressure ac recharge port is the one circled? For reference, it’s a 2013 BMW 640i (N55).

I did a quick search on acpro’s port finder page and it showed that it’s under the passenger side air box. But as you can see in this picture, neither ports were under the box. Then I did a search for a 535i and the engine bay was the same. And it showed the circled one which is right next to the positive battery jump spot.

[Qsilver7]

I forget which one is the high and which is the low….but see pic below for the other port (circled in red) up front in the opening on the left side (as you stand in front of the car). The AC fittings are designed to only accept the one they are made for…so which ever fitting connects…will be either the one circled in yellow or the one circled in red in the pic below.

EDIT: just checked the part database (bimmercat.com) and the diagrams lists:

• #2 as the pressure line (circled in red in the pic of the engine bay)
• #3 as the suction line (circled in yellow in your pic of the engine bay)

[xidamaaa]

Originally Posted by Qsilver7

I forget which one is the high and which is the low….but see pic below for the other port (circled in red) up front in the opening on the left side (as you stand in front of the car). The AC fittings are designed to only accept the one they are made for…so which ever fitting connects…will be either the one circled in yellow or the one circled in red in the pic below.

EDIT: just checked the part database (bimmercat.com) and the diagrams lists:
#2 as the pressure line (circled in red in the pic of the engine bay)
#3 as the suction line (circled in yellow in your pic of the engine bay)

Thanks for pulling out this diagram! So I should use the suction line (circled in yellow) is that correct?

[Qsilver7]

As previously stated…I’m not entirely sure because I’ve never had to recharge either of my F06s…but I do know that if you are attempting to recharge the system….if you are using R134a or even the newer refrigerant…the fitting will only go on the correct one.

If I had to guess off the top of my head…I think it’s the low pressure fitting is where you connect to recharge…which would be #2 in the diagram.

Hopefully those that know for sure that are reading this thread will chime in with any corrections. But if no one else chimes in…see which fitting your equipment will actually attach to. It won’t go on the wrong fitting.

[MotionMan]

Yeah I believe Qsilver7 is absolutely right on that.

The recharge/top up kit will only fit one port (filler is higher than the drain port as the lower drain port is used to vacuum drain if a garage with the right kit needs to completely drain the system for maintenance)

I’d also advise a cannister of oiler/sealer too, this contains a mixture of r134a and oils and other stuff that lubricates the o-rings etc in the system to stop them drying out and perishing.

[xidamaaa]

Originally Posted by MotionMan

Yeah I believe Qsilver7 is absolutely right on that.

The recharge/top up kit will only fit one port (filler is higher than the drain port as the lower drain port is used to vacuum drain if a garage with the right kit needs to completely drain the system for maintenance)

I’d also advise a cannister of oiler/sealer too, this contains a mixture of r134a and oils and other stuff that lubricates the o-rings etc in the system to stop them drying out and perishing.

Thank you! Yes I got a can that has leak sealing formulas that claim to seal rubber rings

[Luftpost]

Found this....made me chuckle when I listened to the hood opening instructions. Plug in your car info and it will guide you through it. I just did this on my X5, works great now.

You cannot mess up the connection since to low pressure is a different size than the HP.

Let us know how it goes.

L

[xidamaaa]

Hi all,

Appreciate all the help here! I can confirm that the low pressure port is a different size and the adapter that comes with self recharge kits will only fit the correct port.

In this case, the low pressure ac port is the one located right next to the positive battery jump terminal(circled in yellow).

It turned out my pressure was low at 15 psi so I charged it up to 35. The hissing sound from the center vent that I could hear every time I turned on the ac, went away! And the ac just became much colder faster! Such an easy and cheap solution. Hope this is helpful to others, especially when we are in the summer now😉

[Qsilver7]

Great! Thanks for the update along with the correct port info...glad you got things working.