glhracing wrote:Well after completing a full 1.5 years of house heating+ domestic hot water and heating i thought I would share some thoughts.
First off I love this unit. Yes, there were some short comings with lack of air in the begining but they have been taken care of. I am running a power vent so I have to balance feed air with exhaust air. I can't run the fan completely open on the feed because I will essentially have no draft.
I have found that running the feed rate slightly higher than normal allows faster response as well as a little greater heat output (measured) because the coal bed thins out a little bit and passes more air. In other words i run the feed rate high enought to spill out a little bit of hot coals. This has not changed actual coal usage over the course of the heating season because we are actuall getting more heat out of the coal as proven by water temps/flows. I run the feed screw 2 full turns out from completely seated. This is just about as much as the stoker can push, just 2 more turns and that would be it unless I put more threads on the feed screw.
I also find that a rice coal size nearing buck is more advantages than pure rice. Luckily my coal source (blashak mine i'm told) comes this way. Infact it has some larger than buck and this actually burn hotter as proven again by water temp/flow.
so for those that have a lazy flame, try turning up the coal feed rate a bit more, yes it is a counter intuitive to watch a few hot coals fall off the edge but perhaps your coal bed is (packing) to much as mine was and this will thin it out a bit. My flame used to be about 2 inches from the diffuser with the new fan and with the method described above the flame will wrap around the diffuser on both sides. Watching it do this puts a smile on my face.. Some nights i grab a cold beer and just watch the flame and turn on the hot water just so the boiler has a call for heat.....
My specs are :
- feed screw 2 turns out from full in
- Draft above fire is .05"
- new fan with 1/6 opening covered
- powervented at full speed
- 5 gpm coil
- HL 185 / LL 179
- heating 3600 sq ft at -15 this morning and 70 degrees inside with an endless hot....actually scalding shower this morning. nice......
any questions feel free
This is precisely the issue I'm having, and I haven't had the cojones to pull the trigger on changing the settings yet.
What else did you have to change when you went 'all in', so to speak?