How hot is too hot?

How hot is too hot?

PostBy: stanpjrh On: Sat Dec 22, 2007 9:17 am

Hi everyone, I am new to the site, have enjoyed reading past posts and joined up. I have been burning coal for 21 years in hand fired stoves. I just purchased and installed a used harman mark III and love it. The fanco belge I have been using worked great but was just a little to small for the house.I don't want to wreck this stove because I'm still learning how to burn it. Can i really crank this thing, is 2 turns on the bottom draft knob ok? I know all chimneys are different,is there a rule of thumb?Stan in pa. 30 miles from the best anthracite in the world and loving it. Thanks for any replys in advance.
stanpjrh
 
Stove/Furnace Make: harman magnafire mark III

Re: How hot is too hot?

PostBy: titleist1 On: Sat Dec 22, 2007 10:12 am

I run my Mark III at 2 - 2-1/2 turns with no problems. My stack temp runs between 200* - 300* F with a mag thermometer about 18" above the stove. As you said, depending on conditions (outside temp, wind, coal quality, how full the ash pan is, etc.) this may have to be adjusted a little. When I run it through the night, I will have it at 1 turn (got me from 10:30 last night to 7:30 this morning and there was still a very strong fire this morning), when I am kick starting it in the morning I will turn it all the way open for maybe 15 minutes while doing the coffee & dog chores, then I'll turn it back in.

I just had to replace a Mark III after 14 years because the heat baffle warped and cracked the sides of the stove. I had liked the first stove and got another Mark III to replace it about a month ago (easier to fit existing stove pipe configuration, too!). Since you said yours is used, I would check the condition of the baffle. My theory on mine is that the top of the baffle flaked away over the years making it thinner and less able to handle the temps inside the stove. I don't know if it was because of the chemical make up of the ash, moisture during the summer from being in an unfinished basement, or a combination, but it was definitely flaking and thinner toward the center of the stove.
titleist1
 
Hot Air Coal Stoker Stove: Harman Mag Stoker (old style) one in basement, one in workshop
Hand Fed Coal Stove: Harman Mark III on standby for long power outages
Coal Size/Type: Rice/Anthracite; Nut/Anthracite

Re: How hot is too hot?

PostBy: stanpjrh On: Sun Dec 23, 2007 12:11 pm

Titleist1, Thanks for the reply. I love this stove & probably should have purchased one years ago. With oil toping $3.00 a gallon it was time to get a little bit larger stove. I'm curious to see how cold it can get before I need the oil furnace to help. I have a mag thermometer at about 18 inches above the stove top ,right below my baro damper & have a temp about 175 degrees with air control opened about 1and 1/2 turns burning pea coal. I am getting a load of nut coal to use, as the pea is just a little to small. I had the pea left from my franco belge. Were you ever able to repair your other stove? I have mine in an unfinished basement also & am considering putting a light bulb in the firebox for the summer to keep it dry. Thanks again for the reply
stanpjrh
 
Stove/Furnace Make: harman magnafire mark III

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Re: How hot is too hot?

PostBy: titleist1 On: Sun Dec 23, 2007 1:12 pm

I did not opt to repair. Fixing the cracks would have been possible, however the baffle would also have to be cut out and replaced since I thought with it (the baffle) being much thinner than designed it would never handle the heat again and would have kept stressing the sides of the stove. I guess that says a lot about the welds since they survived over the sheet metal itself. I burn nut coal myself. Our place is a ranch about 2000 sqft and the stove does quite well heating it. If I keep the stove burning at a high level (2-3 turns), the furnace won't kick on at all even in our coldest weather. The LR/DR/KT area stays about 72 and the bedrooms about 65 (we like it cooler there for sleeping). From reading a lot of the posts here, it seems the layout of the house and strategic location of the stove goes a long way to efficient and comfortable heating.
titleist1
 
Hot Air Coal Stoker Stove: Harman Mag Stoker (old style) one in basement, one in workshop
Hand Fed Coal Stove: Harman Mark III on standby for long power outages
Coal Size/Type: Rice/Anthracite; Nut/Anthracite

Visit Hitzer Stoves