Newbie with a combo furnace

Hey y’all I’m new to heating with coal, my only exposure to this in the past was seeing my grandfather burn coal when I was very young. So because of the price of oil I decided to give black gold a shot. Bought my first ton of oiled nut coal and have it stored in the bin next to the furnace in the basement. My furnace has a MPD and Baro. Baro is set at 0.06 and mpd closed. Fortunately previous homeowner gave me some tips and now that I keep the MPD closed I am able to keep the fire going for 6-8 hours easy. It’s anything longer than that where I start to struggle. I think maybe I was shaking too aggressively and cutting off air through the bed? I’m putting about 3 hods on at night as the grate is huge 24x36. I need to get to 10-12 hours of consistent burn time. Any suggestions would be super helpful and appreciated. Finally today I at least got the house temp from 74-78 as compared to 62-66 the earlier part of this week.

Welcome aboard , you want to load up to the top of the fire brick on the edges and a mound in the middle (more coal = longer burns )

ShawnLiNy wrote: ↑

Sat. Nov. 19, 2022 9:09 pm

Welcome aboard , you want to load up to the top of the fire brick on the edges and a mound in the middle (more coal = longer burns )

Yup, what he said. Filler up.

So would you say judging by the picture I posted I just need to add more? Thanks!

Coal bed has to be even to prevent air from bypassing the coal bed, as in the two rear corners. Old furnaces used to come with a tool that had a steel shank and a flat piece of steel on the end to use as a rake to even out the bed.

You need a bed about 8 inches deep all over. That nut coal is on the large size.

I would investigate how to make the coal bed shorter. Depends on the shaker design.

franco b wrote: ↑

Sat. Nov. 19, 2022 9:20 pm

Coal bed has to be even to prevent air from bypassing the coal bed, as in the two rear corners. Old furnaces used to come with a tool that had a steel shank and a flat piece of steel on the end to use as a rake to even out the bed.

You need a bed about 8 inches deep all over. That nut coal is on the large size.

I would investigate how to make the coal bed shorter. Depends on the shaker design.

I was thinking the same thing. The grate can easily hold 50lbs. I just loaded it up for the night and it looks more even to me and consistent 76 degrees today. Here’s how it looks tonight

Probably needs closer to 100 # to be full

ShawnLiNy wrote: ↑

Sat. Nov. 19, 2022 9:31 pm

Probably needs closer to 100 # to be full

So I should layer some more on top of there tonight

I agree, get 100 pounds in there and you'll get your longer burn times

Sean.obrienpac wrote: ↑

Sat. Nov. 19, 2022 9:34 pm

So I should layer some more on top of there tonight

Yep, 3 more hods.

Sean.obrienpac wrote: ↑

Sat. Nov. 19, 2022 9:34 pm

So I should layer some more on top of there tonight

To the top of the bricks and heaped in the middle.

What if my blue flame on top goes away when adding? That too much?

Sean.obrienpac wrote: ↑

Sat. Nov. 19, 2022 9:43 pm

What if my blue flame on top goes away when adding? That too much?

If you are wondering if adding more will smother it out, don't worry that won't happen. Give it plenty of over fire combustion air to help prevent a puff back, until the fresh coal is burning good, then you can turn the over fire combustion air down but not completely off.

Lightning wrote: ↑

Sat. Nov. 19, 2022 10:02 pm

If you are wondering if adding more will smother it out, don't worry that won't happen. Give it plenty of over fire combustion air to help prevent a puff back, until the fresh coal is burning good, then you can turn the over fire combustion air down but not completely off.

I read your mind! That’s exactly what I did. Just closed the over fire damper and it’s burning HOT

Perfect, there ya go! Adjust your primary combustion air (under fire air) to achieve the heat output you want.

This thread was a major help to me . I need to get better at asking questions . Myself to just started burning and this is my 3rd day . I just tended like the following advice and I too was not shoveling enough coal in . It’s hard when your used to soft coal . Anthracite is a totally different beast , and I sure like it !