Okay, some updates. And a bit of "How to dial in a stoker"
First, the tag on the stoker is "K-2" not KAA-2. Same animal?
Second, A MANOMETER is ESSENTIAL!!!
Third, A MANOMETER is ESSENTIAL!!!
Found that draft was a real problem. Upon inspection found a few things that needed fixed now and some for near future.
1. Outside termination vertical tee (you know with the little hat on the top and open on the bottom) is too close to the ground. IIRC it should always be above the snow levels. 12-24" or something? In any case, we will eventually add an elbow and extend it about 4-5ft vertically. Goal is a *little* natural draft in case of power outage to avoid CO or other problems.
2. Inside 4" pipe needs more rise on the horizontal run. In a condensing natural gas furnace the piping is sloped to the outside, but solid fuel/coal needs to have a bit of help for a little bit of natural draft.
3. When pulling the pipes to clean out everything, still no draft (with fan running). So opened the back side of the direct vent motor pipe/cleanout and cleaned it all out. Look at the little Tee handle to the right side in this pic. It has an allen wrench in its set screw.
Loosened that set screw and the tee wouldn't move. It is supposed to slide IN for less draft, OUT for more draft. Tapped it a few times, vacuumed from the clean out, used my hands to feel for any obstruction and such.
Now it moves freely and the fan can make .06 or so draft!
Anyone want to guess how we knew there wasn't ANY draft? Cough, cough, LOL.
So now we light the fire again and it starts to burn okay but with a lazy flame. Close down the combustion fan and reset the draft to .03 (for testing/safety margin). Burns much better.
But it runs the fire to the end. I cut back the feed 3 turns.
Then it is just a tiny strip. Turn it back up 2 turns. Fills 3/4 of the bed but with 'cold fire' (lots of black instead of molten looking) and not heating water well.
So I increase the combustion air and reset the draft using the Dwyer Mark II. Did this 2 or 3 time, a little at a time.
Then it is burning completely before it gets to the end. A little too much ash at the end. So I turn up the feed again. A little more combustion air, reset the draft to .015 (spec is .01-.02 over hot fire)
Looking like a better fire but now the water is 135 and zones calling for heat, so it can't catch up. Turn on OIL boiler, all valves open. It satisfied water temp but the K2 is still at about 135F.
Yeah, we'll have to add a pump as mentioned waa-aaay back. But at least we know that BOTH can be on at the same time and nothing EXPLODES! Haha.
Another problem is the aquastat on the oil boiler only goes down to 180F. We'll need to change that if we are going to leave them both on and set the oil boiler to a low temp to kick on (assume out fire). Will add a relay to break power to K-2 when oil boiler takes over. Make it automatic.
So now I am out of onsite time, having been there for 6 hrs.
I'll be calling and checking on him about every hour or two. Maybe head back out later if needed.
If we can get the full-on stoker fire work out as reliable and hot, I'll work on settings for the timer for low-demand times. And then he'll be set!
"What do you do about the dust?" - 'Let me tell you a story about a coal vac...' - To Be Continued!
