AHS called me back yesterday and I will be emailing pictures of the grate motor and the control box. I guess some changes have been made and he wants to look at what model I have.
Heard the same, could be the coal? Something clogged? Did I clean the furnace this year ? Did I loose draft? I explained I could run 4 ton without any issues and the temp outside could be 65* and never have an issue.
My draft is a 8" flue and I am using a digital manometer to verify the .02-.06 draft. The final answer is to lower the SV to 113 and 3 diff. way below than the manual recommendations. I guess he is also going to look into some of the changes they made on the newer models that the grate only ashes with the fan on and so many seconds before the fan shuts down. I guess what bothers me is the fact they act like they never had this happen before and it can be expected depending on the coal.
I guess I have no option but to lower the Sv and hope for the best. As others mentioned the manual leaves a lot ot be desired and tells you not to lower the SV below 120. My question is what more can you do ? I am using Blackshak coal ;Installed the best 8" stainless flue with a good draft that is monitored;The boiler is sitting in a brand new building and can burn 2 ton or more without any burp or issue. Works great for heat output and purs like a kitten the majority of the time. Then out the blue will blow everything apart
I understand the learning curve of burning coal. If you got draft, good coal(Blackshak), settings as recommended, what more can you do? This is a design issue that needs to be addressed.