Cool growers in the windowsill

[MCSchrum]

I've got a question for you veteran windowsill growers out there. Have any of you had success with blooming cool growing orchids, or orchids that require a cool dry winter rest? I have several orchids that fall into these categories, and so far I have had minimal success in blooming them, though they grow just fine.

I believe the problem is that I haven't been able to keep them cool long enough to initiate blooming. During the fall, I keep the windows open in my growing room as long as the night time temps stay above 40 or so. Below this, it is just too cold, and I have to close the windows. I eliminate fertilizer to these plants, and reduce or stop watering, so I don't think that is the issue.

I have 2 T5s and an LED lighting fixture, and they produce a fair amount of heat. It's been pretty warm in MO so far this fall, and during the day, the temps in my growing room can get up into the low 80s F. I've got 2 oscillating fans to keep the air moving, but this doesn;t reduce the overall temp in the room. My intermediate and warm growers bloom just fine. Has anyone had more success with their cool growing orchids indoors?

The plants I'm growing include:

Dendrobium kingianum
Dendrobium loddigesii
Dendrobium unicum
Coelogyne cristata