i use this one. works great.
it turns the co2 off when the cooling fans are on.
you set the day/night temps and humidity levels
set the co2 level
plug in your co2, dehumidifier, and cooling fan. it takes care of everything and tells you max min
i just re-red your post. you dont need to heat up your air. you only need to pull fresh air in once every few hours. (i dont know the exact numbers as i use co2)
so if you dont have a controller. you have to figure out how long it takes your room to heat up to say 80F after lights on. then have your fan kick on and cool the room down till its at say 70F this will cool your room and pull in some co2 from the adjacent room or outside at the same time. provided you are pulling air into the room and through the lights, and out. you only need to pull cool air in to cool the lights when they get too hot. if they stay cool, then just some circulting fans and kicking on the ventilation every few hours will work fine. i dont know your exact setup so its hard to say. but its a lot eaiser to use cold air to cool your lights and pull in some fresh air periodicaly. then to heat up air.