Hi, I am new here. I have a Regency I2400 Medium fireplace insert (wood burning of course)! with a Stainless steel flex liner ( one piece) connected. I have a question about the stove top temp vs. the temp of the liner. Is there a general rule of thumb regarding the temperature differences? I mean, if my stove top is 500 degrees what is the temp of the liner? 300 degrees? I have a homesaver magnetic thermometer on the top of the stove and I usually keep it around 500 degrees. I would like to know if this is hot enough. I am guessing that the liner is around 200 degrees cooler.. Is this a safe assumption? Thanks