I have severe chronic achilles tendonitis in my left achilles. For 18 months I had both achilles flared up and was off the bike for a year... Mine came about from backpacking/hiking over the course of 3 years. Anyway, I digress.

Remember you achilles don't have strong blood flow, so while ice feels nice, they also need blood flow. The cold/hot/cold/hot helps.

I concur with Oakleaf on everything suggested.
Another helpful massage - get on your hands and knees, take one knee and place behind the other knee high on your calf and knead you calf with your knee, all the way to the ankle then switch legs. I find this super effective. I massage my achilles with my hands several times a day as I am sitting at my desk.
Consider ASTYM treatment if it isn't getting better. (a good PT certified in ASTYM) this is what finally got me back on the bike - as well as multiple stretching exercises.
Oh and I also own my very own ultrasound from mendmenow.com or mendmytendons.com when I am feeling especially tight I do a week of self ultrasound, it gets the blood moving.
Good Luck, I have had to learn to live with mine. Am not going to have a tendon replacement unless everything falls apart