i searched a bit before posting and didn't find what i needed, so here goes:
i have 1995 325i that i plan to keep for another year (new e90) and the a/c doesn't blow cold. i found the following directions on another board, and i wanted a second opinion:
(i live in nor cal, so this isn't critical. if i can have a low cost solution that might work without risk, i'll try it.)
**********
You can recharge your air conditioning system for less than $20.
Disclaimer: This DIY is not intended to diagnose your a/c problems. If your a/c isn't cold, it may be suffering from something more severe than just being low on refrigerant. Proceed at your own risk. Use safety glasses. Batteries not included. Offer void where prohibited.
Open your hood. Look at the decal above the right headlight. It should tell you what kind of refrigerant is in your a/c system. If it is anything other than R-134a (like R12, freon, nutra sweet), this DIY is not for you. You must have R-134a. If not, this procedure is illegal for you.
Go to Wal-Mart, K-Mart, etc., and buy this R-134a recharge kit:
You will need the one with the hose attachments, T-valve, and pressure gauge. For subsequent recharges, you'll just need a can of refrigerant because you can reuse the hose, T-valve, and pressure gauge. The refrigerant can in this particualr kit contains the necessary lubricants for your system's O-rings. Occasionally a/c leaks can be blamed on dried out O-rings, and the lubricants (to a reasonable degree) help keep the O-rings conditioned. Bad leaks will require professional repair, however.
Read the instructions on the package. Connect the pressure gauge to the hose. Find the low pressure line of your a/c system. The connector is against the firewall on the right side of the car. See below:
Connect the hose with the pressure gauge to connector 2 in the picture. It is hard to screw up because the hose will only fit on 2.
Ignore the pressure recommendations on the package. Refer to the table below, which was adapted from a chart graciously provided by GPappas at bf.c.
This table lists the recommended Low Pressures, given the ambient temperature and Relative Humidity (RH %). For example, if the RH is 50%, the outside temperature is 80°F, the Low Pressure side should be 36 psi. This table works for all BMWs with R-134a. If you don't know the current RH and temp in your location, visit http://www.weather.com and enter your zip code.
If the pressure is below the recommended pressure, you need a recharge. If the pressure is higher than the recommended pressure (give or take a few psi), you have other problems not covered in this DIY. For that, I can post a simple (as in Mickey Mouse simple) troubleshooter if there is interest. If the pressure is just about at the recommended pressure (give or take a few psi) and your a/c is still warm, you have other problems not covered in this DIY.
After you have determined that you need a recharge:
Remove the hose & gauge from the connection on the car. Remove the pressure gauge from the hose and connect the hose to the T-handle. Connect the T-handle to the refrigerant can. Reconnect the hose to the connector in the car. Shake the can vigorously, hold it upside down, then turn the T-handle clockwise to puncture the seal on the can. Then turn the T-handle countercloclwise to allow the refrigerant to be sucked into the a/c line. The can will get noticeably cold as the refrigerant is piped through.
Depending on how low your system was, you may use up the whole can. Do a little at a time to prevent overcharging, taking pressure readings as you go. You will also get a feel of how much psi increase you get per given time of sucking.
Have a beer.
i have 1995 325i that i plan to keep for another year (new e90) and the a/c doesn't blow cold. i found the following directions on another board, and i wanted a second opinion:
(i live in nor cal, so this isn't critical. if i can have a low cost solution that might work without risk, i'll try it.)
**********
You can recharge your air conditioning system for less than $20.
Disclaimer: This DIY is not intended to diagnose your a/c problems. If your a/c isn't cold, it may be suffering from something more severe than just being low on refrigerant. Proceed at your own risk. Use safety glasses. Batteries not included. Offer void where prohibited.
Open your hood. Look at the decal above the right headlight. It should tell you what kind of refrigerant is in your a/c system. If it is anything other than R-134a (like R12, freon, nutra sweet), this DIY is not for you. You must have R-134a. If not, this procedure is illegal for you.
Go to Wal-Mart, K-Mart, etc., and buy this R-134a recharge kit:
You will need the one with the hose attachments, T-valve, and pressure gauge. For subsequent recharges, you'll just need a can of refrigerant because you can reuse the hose, T-valve, and pressure gauge. The refrigerant can in this particualr kit contains the necessary lubricants for your system's O-rings. Occasionally a/c leaks can be blamed on dried out O-rings, and the lubricants (to a reasonable degree) help keep the O-rings conditioned. Bad leaks will require professional repair, however.
Read the instructions on the package. Connect the pressure gauge to the hose. Find the low pressure line of your a/c system. The connector is against the firewall on the right side of the car. See below:
Connect the hose with the pressure gauge to connector 2 in the picture. It is hard to screw up because the hose will only fit on 2.
Ignore the pressure recommendations on the package. Refer to the table below, which was adapted from a chart graciously provided by GPappas at bf.c.
This table lists the recommended Low Pressures, given the ambient temperature and Relative Humidity (RH %). For example, if the RH is 50%, the outside temperature is 80°F, the Low Pressure side should be 36 psi. This table works for all BMWs with R-134a. If you don't know the current RH and temp in your location, visit http://www.weather.com and enter your zip code.
If the pressure is below the recommended pressure, you need a recharge. If the pressure is higher than the recommended pressure (give or take a few psi), you have other problems not covered in this DIY. For that, I can post a simple (as in Mickey Mouse simple) troubleshooter if there is interest. If the pressure is just about at the recommended pressure (give or take a few psi) and your a/c is still warm, you have other problems not covered in this DIY.
After you have determined that you need a recharge:
Remove the hose & gauge from the connection on the car. Remove the pressure gauge from the hose and connect the hose to the T-handle. Connect the T-handle to the refrigerant can. Reconnect the hose to the connector in the car. Shake the can vigorously, hold it upside down, then turn the T-handle clockwise to puncture the seal on the can. Then turn the T-handle countercloclwise to allow the refrigerant to be sucked into the a/c line. The can will get noticeably cold as the refrigerant is piped through.
Depending on how low your system was, you may use up the whole can. Do a little at a time to prevent overcharging, taking pressure readings as you go. You will also get a feel of how much psi increase you get per given time of sucking.
Have a beer.