Hello, My Superior fireplace (Model # DR-600CMN) is about six (6) years old. It is direct-connected to a natural gas line. Up until recently, everything was fine, but now, The flame tends to go out, and I have to flip the wall swtich SEVERAL times to get it to re-ignite. Sometimes it doesn't, and I have to wait 20 minutes and try again. What could be the problem and how can I fix IT...HELP ! Its cold in N.H. :)