If you can get Superthrive or any other type of hormone stimulant and soak the new medium in it for 20 minutes this can be done while you are cutting back the dead roots and preping your chid for its clean home. After you have repotted the plant I would give it a heavy watering at first than let it set for a 7-10 days without watering. Make sure before watering again that the medium is dry upper 1/2 of pot. Keep your normal watering regimen thereafter. Make sure your newly repotted orchid is in low to medium light for approximately 3 weeks. I have used this regimen with all my repotting and works well for me. Let us know how it went.

Aboard, please stop by like Sue mentioned the "introductions" and let us know a little bit about yourself and your orchid addiction and types you grow. Good luck....