Direct Vent FP keeps turning off by itself! Please help!
We have a Lennox Superior Direct Vent fireplace (model SLDVT40NE) that was recently installed. Our fireplace is controlled by a switch. Most of the time after we turn it on and it burns for sometimes hours before turning off by itself! It will occasionally turn back on by itself right away (in a second or two) and other times it stays off for minutes/hour before turning back on.
Our FP retailer and installer, who came highly recommended, isn't completely sure what causes this. Unfortunately, since it takes so long for this to happen, the FP tech is never there when it does happen! One of the original guys from the FP company said it's probably the ignitor and replaced it, but the problem still happens. I called up Lennox and their tech support seemed a little stumped. She thought maybe there was a problem with the switch which wasn't make a good connection?!
So, any idea of what's causing this? Does the fireplace have an automatic shutoff if it gets too hot or isn't venting properly? The Lennox rep said this fireplace doesn't have that feature. Could it be possible that the vent has some sort of obstruction? I can't explain why the 'turn-off' time is so variable though!