The combustion chamber of the Buderus boilers are surrounded by water with
no refractory materials so that means the walls of the chamber are pretty
much the temperature of the water. I call it a cold chamber because there's
not enough heat to burn off the stray particles compared to a fire brick or
refractory lined chamber where the refractory gets a very bright orange to
white hot. I like that feature about Buderus because more heat gets
transfered to the water instead of heating up refractory material. I have a
G115-WS5 and it has easy access to clean it. I burn WMO, and if you're
going to burn WVO or WMO, you are going to have to clean it to keep it
running at maximum efficiency. When you burn WVO or WMO the best thing to
do is to achieve the hottest possible flame to burn the oil. They can be a
real pain to get setup because the burner has to be near perfect to get
little oil left over in the combustion chamber and no matter what you do,
there will still be some oil spray that will escape the flame. I don't have
a problem with that in mine, but I spent alot of time studying it to get it
just right and a very efficient oil and air preheater is one of the key
elements here. Any modified burner will burn great in a refractory lined
chamber with no issues, but if you really want to know how efficient your
burner is working, running it in a cold chamber will tell you that real
quick. So, my boiler is smaller than yours but I do burn 1 GPH per hour.
The problem is a little more of an issue with WVO than WMO, but what some
of the waste oil boiler companies are doing to fix the problem, including
the Buderus boiler is to put a stainless steel liner in the combustion
chamber. This will get much hotter than the boiler walls and burn off the
excess spray that gets away from the flame. The liner should be a diameter
that will give you at least a 1" - 1.5" gap between it and the boiler
chamber all the way around, and you should have enough spacers to keep it
centered in the combustion chamber, but it should be around 5 or 6 inches
short at the back end to allow the exhaust gasses to flow back around it to
get through the passages in the boiler.
Andrew.