Ask-a-Dave's-Gardener: Oncidium roots turning little brownish after repotting, 1 by Riasebastian

Riasebastian wrote:
My oncidium ,about an year old(dancing lady)has got two healthy pseudobulbs n leaves plus one psuedobulb on growing stage. I repotted it two weeks back. At first roots were white with shiny green tips but After a day or two their roots started to turn gray and now little brown. Otherwise they look healthy. Temp is 36 degree high and 22 low. I do water them when they start to dry out. Do give weekly fertilizer. I didn\'t receive a bloom yet is the sad part. Please tell me whether they are dying. I guess you can see the difference from two pictures