Harman Mark ll-A Summer project

I did a shakedown at 12 noon(24 hrs lit). Added 1/2 bag(20 lbs.) Opened the primary to 3/4 turn..that brought the stove temp up to 200*. I'm now running the blower and, unlike the Chubby, it's not 'scrubbing' heat off the stove. The Chubby would scrub 50* with the blower on. ???????? Is this because the stove is only idling? Do the Harman MK series scrub heat when the OAT get colder with the blower on?
Cheers

Grats!! I have found I need to keep top side at about 260 minimum to keep the fire going, but the way the barrow
is dropping and wind picking up, may have to shut it down more.
temps I measure with the IR gun, my magnets are anywhere up to 100 degrees off sometimes.
Post a pic !

This stove looks identical to my Mark III. I checked for gap in my stove there, no gap there is a weld there on my stove. As of today 12/4 i still can't get my stove to burn coal. Will burn wood no coal yet and its been cool at nights 20-30 maybe only highs around 40 can't figure out what is going on. last year coal was burning when it was 70. Stumped.

Is the coal any different than last year?

Nope, coal is the same.

Felix the Cat wrote: ↑

Sat. Dec. 04, 2021 12:07 pm

This stove looks identical to my Mark III. I checked for gap in my stove there, no gap there is a weld there on my stove. As of today 12/4 i still can't get my stove to burn coal. Will burn wood no coal yet and its been cool at nights 20-30 maybe only highs around 40 can't figure out what is going on. last year coal was burning when it was 70. Stumped.

You will need to completely cover the grate. I would grab a bag of match light and cover the grate, open the ash door a little and give it a light with pipe the damper open. Fast heat transfer will get the match light going, then after 5 min sprinkle the coal on, all over, but not thick. give it 5-6 min before adding more. Use a timer so you dont forget. Coal needs to be hot to get it to light. Good luck!
PS make sure your damper is opening.

Felix.......
If the MK III has been sitting 'fat, dumb, and happy' all Summer(no changes)......I would put a mirror in the chimney clean out looking up for sun light, and work my way back to the Harman.
Cheers

Correct me if I’m wrong, don’t wood fires rely mostly on secondary air above the fuel while coal fires must have primary air from below the fuel? If that is the case, then a leak of secondary air would not impact a wood fire but could be detrimental to a coal fire.

Jerrybro wrote: ↑

Sat. Dec. 04, 2021 5:12 pm

Correct me if I’m wrong, don’t wood fires rely mostly on secondary air above the fuel while coal fires must have primary air from below the fuel? If that is the case, then a leak of secondary air would not impact a wood fire but could be detrimental to a coal fire.

This is fact! suspects are usually the door/ door glass. Harmon uses a door glass vent to help make the "swirl" effect happen above the door. When I restart after a edge clean out every so often, when I shut the bottom and the top I can hear the air squealing at the bottom of the glass. Its not much, but does the trick and helps keep ash off the front Glass, to a degree.

Jerrybro wrote: ↑

Sat. Dec. 04, 2021 5:12 pm

Correct me if I’m wrong, don’t wood fires rely mostly on secondary air above the fuel while coal fires must have primary air from below the fuel? If that is the case, then a leak of secondary air would not impact a wood fire but could be detrimental to a coal fire.

There is some truth to what you say. But a wood fire will burn with primary air and secondary also. This really cant be said for coal, at least not for anthracite coal, as it needs primary air to make it work well.
Wood will burn more intensely with air under than air over, will will burn both ways.

Felix, start a new thread and go over your lighting procedure. Suggestions will follow.