I've been busy the past few weekends trying to finish up this project before I'm wearing shorts again.
It doesn't help that Blaschak is up to $375/ton out here, and my natural gas cost is down to $0.65/therm TOTAL cost. Nothing against NEPA, but it's time I spent my money on ILLINOIS coal.
The base design was finalized and fabricated from 1-1/2 x 3/16 angle and 13ga. sheet, welded
together. Flue outlet is 6" with an access panel opposite for fly ash cleanout and a fire door on the front for clinker removal. I stuck the stoker in from the side so both doors would be on the front and I wouldn't be tripping over the stoker tubes.
I then painted the base with BBQ black Rustoleum, choosing the color simply because I couldn't get any other high temp paint in a can - everthing else was spray bombs and I didn't want to spray inside and it's way too cold to spray outside. I used a short nap trim roller and it worked most excellent.
Finally I plugged the stoker into the base, made up a fill panel (laying on top of the base in the picture) to close out the opening, and now I need to fill in around the retort and place the hearth. The base to pot heights worked out (not sure by accident or on purpose) so that a layer of brick as a floor leaves just enough height for a row of vertical brick all around (9") that fit under the angle iron top frame. I'll take pics when it's finished - it will be more clear then.
Today I need to go and blow a wad on 150' of 1" copper, fittings, uni-strut clamps, and pipe insulation. I've already got the uni-strut mounted to the basement concrete to route the water to the furnace plenum.
Controls will be handled by a CuBloc PLC using a National Instruments LM34 temperature sensor mounted into a homebrew thermowell. I'm not using any PID control - just simple on-off limit control at this point (basically an electronic version of a Honeywell) and the PLC will also function as the stoker idle timer. A second thermostat will be hooked to the main thermostat in the house - the R-W connections on the new stat hooked to the R-G connection on the main stat. Therefore the call for heat will activate the blower only. This will signal the PLC (using a 24VAC coil cube relay to close the 24VDC control circuit) to fire the circulator and a 24VAC solid state time delay relay that will delay the blower up to 60 seconds to allow the fan coil to get warm. I ran direct bury Ethernet cable along with the pex and I will mount a small indicator box by the thermostats with green (stoker ON) and red (alarm - outfire, overtemp, etc) LEDs for status using two of the remaining 3 wire pairs.
Later I can get fancy and add zones for either the boiler building/shop (if it needs additional BTU), the main house garage, or a separate basement loop with a big baseboard. The basement gets REALLY cold in the early spring when it's warm enough during the day the heat doesn't run much so all the cold air collects downstairs. I might also add a display and/or keypad to the PLC, but it's simply not needed at this point.
Enough babble - on to the pics: