Have Lopi Berkshire for about 5 seasons. Like it but for the past 2 years I've been dealing with the burner just shutting off on me. The pilot has always stayed lit. If I turn off it will relight but will make a quick flash and then start as it used to by flame moving from back to front much slower. Talked to dealers and tried the following: Replaced the thermopile, replaced the thermo couple, cleaned pilot with compressed air can, removed burner and cleaned with vacuum. I do not have a thermostat on it. About 2 years ago, I switched from 2 100 gal above ground tanks and burried a 500 gal tank. My gas provider performed the work and hook up. Not sure but think the issue may have started the season after this. They mounted some kind of regulator looking thing on my outside wall which then feeds the heater and my cookstove/ oven. Could it be something with that? Any help would be greatly appreciated. The stove was professionally installed and seemed to work well for a couple years. Although the installer was a crook (long story) I will never call him back.