How to qualify move from water wash SMT process to No clean?

We design PCBAs. Our CM assembles the boards for us. So far we have used waterwash SMT process to build the boards. Accidentally, due to documentation errors, we suddenly have a huge batch of boards built with No-Clean process. Although the boards pass our ususal functional tests and everything looks good, I need to do a formal qualification of these boards from quality and reliability stand point before we can use it in the products. Can anyone shed light on how to do so? the boards are 10 layers, stuffed on both sides, uses numerous BGAs with 0.8mm pitch, uses 0402 size caps and resistors and various other ICs.

Also, in general, CMs want us to switch to No-Clean for all boards...i need to anyway evaluate moving in that direction. So any and all info on this subject is very welcome.

Best Regards.

reply »