Barry Assuming you start with tap water, a single stage RO removes about 90 - 95% of the impurities with good membranes, so, typically, a 500 uS-cm water will come out with a conductivity of about 35 uS-cm and a double stage RO about 2 - 3 uS-cm. This would be adequate for most W/S flux/paste removal. An adequately designed double-bed DI purification will produce water with a conductivity of typically 0.3 - 1 uS-cm which is usually perfect for the job. A mixed bed DI system, often used for polishing double bed systems, will produce down to 0.056 uS-cm, which is almost too good and can attack stainless steel welds if the flux is halide-activated! What you choose depends on a) how much water you need b) the purity you need and c) whether you recycle it in a closed loop. In the latter case, more precautions are necessary for successful operation. In many cases of small requirements (< 100 l/day) in open circuit, provided a reasonable quality tap water is available, a single mixed bed system is often used. The capital costs are very low but the running costs are higher. If the tap water contains dissolved iron or some other impurities, you cannot run RO without a pre-treatment, otherwise the membranes will clog. If you care to e-mail me privately, I can guide you further as to the best choice of system, telling me the details of your equipment and process. My recommendation regarding temps is 50°C for the wash (WARNING! a higher temp may result in insoluble residues with many W/S systems) and somewhat higher, progressively, for rinsing. HNY Brian > Barry Gallegos wrote: > > Happy New Years Netters. > > What is the difference between RO water and DI Water and Is RO only a > viable option for a Water Soluble process only. > > Also am wondering what would be a standard wash and rinse temp to use. > > Thank you in advance. > > Barry Gallegos, PE > Western Electronics, LLC > 110 E. 43rd st. Boise, ID. 83714 > P-208-377-1557 > F-208-377-9836 > --------------------------------------------------------------------------------- Technet Mail List provided as a free service by IPC using LISTSERV 1.8d To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt delivery of Technet send the following message: SET Technet NOMAIL Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail Archives Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ---------------------------------------------------------------------------------