On the coldest days I will run the T6 around 650-700 °F during the full bloom secondary burn off. Then it settles down to 600-650 for a few hours. With a full load of locust it might kiss 750 °F for awhile. I try to keep the living room under 74. The rest of the house temps vary with heat circulation between 68-72. But it's all relative. When it's 15 outside and blowing like snot, 72 feels pretty good.