Man you sure change what I said. I run at 2.2 not 3.9 GPH, and maybe run 6-8 hrs a day on average during the many ...many... outages we have had here at home in the 23 years I have had a backup generator. I only run mine enough to keep food frozen, and to stay comfortable in early evening. I don’t need to run it during daylight hours cept at lunch time. But I could run it 24/7 if I so felt like wasting gas. And if I did run it all day and night, the gen would suck about 50 gal or so of fuel per day.