Harman Mark II- House Too Hot?

Ok, guys, here's another brain teaser I need your knowledge on. Got a 1900 ft two story house in Central CT , built 86' with hydronic heat, 6" walls with thermo-pane window, go thru ~700 gallons oil/yr with hot water, maybe more now that my wonderful children are taking 25 minutes showers. Stove will be in the unfinished basement, stairway up is ~12' in front of the stove. With wood heat (Mid Moe) cranked up to a flue temp of ~450* after 3-4 hrs, the 1st floor is toasty with basement door open until around 15* out. The stove generated heat does and will come up thru the floor above the stove regardless of stove fuel. I can close the door to the basement. My question: After the initial start up/firing, is it possible to throttle this Mark II baby down with the blower off so I don't broil my two daschhunds and wife on the 1st floor? Me, I like heat. Thanks for your honest opinions.

The answer is yes.. you can throttle a coal fire back, and keep a good fire going providing you have a good chimney.. The problem usually comes when you try to throttle back a fire when the weather is warm, the reduced amount of heat up the chimney lowers the chimney draft. Once the draft is reduced too much, then the fire doesn't have enough air being pulled throught he coal bed, and the fire can go out..
But most chimneys don't get this problem untill the outside temperature approaches 70* or so..

You can throttle back a Mark II so that the chimney temperature is around 200* rather easily... You will want to install a barometric damper and set it with a manometer or install a manometer to watch the chimney draft..

Greg L

Greg, thank you. I have very little experience with coal except what I've read here so your comments are appreciated. I can deal with some moderate amt of heat as you suggest on a ongoing basis, though I kinda don't want to live all winter on the planet sun if you know what I mean. The alternative energy excitement continues. Smiles and thanks, Bruce.

The coal and Mark II will give you constant even heat. In the spring (now) I turn the fan down or off to keep the BTU output at a reasonable level. This keeps more heat in the stove and helps keep the draft. Properly adjusted “windowstats” keeps the house 68-72 and dry.

Gentlemen, Thanks for the comments. The household (or should I say me) has now committed itself to a Mark II. The dealer also said that since most of the stove's back is actually an heat exchanger, not using the blower with slow burns cuts down on the heat output on a warm day more than you think. I've got a lot to learn though this is a great place to do it. Next....bringing this baby slllowwwlyyyy down the hatchway.

Teenager tip to shorten showers: After they've been in the shower an appropriate amount of time (7 minutes) go to the hot water tank and slowly turn the hot water off. They will think they're running out of hot water and hurry things up. After only a couple of weeks they learn they can't take 25 minute showers. Worked for me!

Uglysquirrel wrote:Gentlemen, Thanks for the comments. The household (or should I say me) has now committed itself to a Mark II. The dealer also said that since most of the stove's back is actually an heat exchanger, not using the blower with slow burns cuts down on the heat output on a warm day more than you think. I've got a lot to learn though this is a great place to do it. Next....bringing this baby slllowwwlyyyy down the hatchway.

One thing your dealer forgot to mention about the blower fan Not only does it wash the heat into the room but it also
helps keep the stove from over heating I never run mine with out the fan on All you have to do is put a thermomenter on it the stove and watch the temps go up with the fan off in about five minutes 300 to 400 degrees turning the fan off does not slow anything down it will do nothing has far has the fire burning goes all it will do is increase the temps on the stove you will be better off keeping it on all the time and ajust the air input to control you temps if you keep you fan off you can over heat the stove pretty quick The first thing that will warp is you baffle Harmans are known for that when there are over heated so tell your dealer to throw in a extra one if he says you can run the stove with out the blower on also tell him to watch the temps on a stove go up with out the blower fan running get yourself a Magnetic thermomenter
for the stove and get a good probe thermomenter for the stove pipe and watch the temps inside the pipe you will be able to controlthe temps much better just by adjusting you air knobs on the ash door that is how you control a hand fed stove

You posted you had hydronic baseboard. You might want to consider a boiler instead for whole house heating. Kids can take showers as long as they like. Scott

stokerscot wrote:You posted you had hydronic baseboard. You might want to consider a boiler instead for whole house heating. Kids can take showers as long as they like. Scott

I would not use a stove in a home with hydronic heat. A boiler is much more efficient and can be operated into much warmer weather than a stove. Your home will be much more even and comfortable and be a lot cleaner, it also reduces some of the work involved depending on your choice of appliance. The DHW off a boiler is just another bonus you can learn to live with.

There is a big difference between the start-up costs of buying a Harman Mk II and buying a coal boiler.. UglySquirel currently has a wood stove set up, so the install of a Mark II is pretty simple, swap the stoves, clean the chimney of creosote, add a barometric damper to the flue pipe and your're done..Too bad you can't find a good used Mark II for a reasonable price..

BUT, If you really want the best, the above statements about a coal boiler are 100% right... Contact your Harman dealer about their VF3000 boiler.. It is a nice unit, Or look at a Keystoker Kaa2, both are about the same BTU output,, just about right for a newer insulated house like yours..

The install will be more complicated.. but the ultimate payback is much better,, you can use the boiler all year, for DHW, and eliminate hot/cold rooms because your baseboard heat will be distributing the heat.. Something to consider with $4.00/gal heating oil.

Greg L.

.

My brother paid $4.18 last week, betcha an easy 5.00 by August. I'm growing into all this, lots of good suggestions, will try the Mark II first, what wood I do in retirement if I had one of those stoker automathings ? Next, a coal bin.

Smiles..