My space is 700-something too. I have mine set to 35 and it runs all the time, rarely getting higher than 23-24, but that may be due to the below zero conditions outside. In temps into the 20s or more, it gets to the low 30s. I don't know if it's the unit or all it can do depending on the weather. I also have vaulted ceilings, which may make a difference.
By Cara Sailsbury