We've got CB's pallet burner in our shop (yeah, we know, not supposed to be indoors). This thing now has a mind of its own. Its got about 4 or 5 years on it now and this year has decided to start backpuffing. Its set points are 175 on, 185 off. It typically has its problems after reaching the 185 setpoint when it is "sitting idle". I can see and hear it thru my office window and have come to the conclusion that it must be female. Most (80% -90%) of the day it operates as it should but once in a while it decides to talk back. Get ready for another, and another, and so on. Its been backpuffing about once a minute for the last 20 minutes. We have somewhere around 40' of s.s. insulated double wall chimney plumbing this thing out. The configuration is out the back of the unit for a horizontal run of about 2', then a "T", then about 40' of clean vertical chimney. Our maintenance guys do a good job of keeping the stack clean. Typically we burn nothing but pallets and plywood scraps, we've also burned chips with some success. Doesn't seem to matter what the fuel source is.
Any ideas what would make this thing burp?
Any ideas what would make this thing burp?