New to Me Harman Magnum. Questions

I picked up a used Harman magnum (not a super) for $650 and so far I love it. I replaced a Jensen wood furnace with this and I must say that I wish I would have switched to coal years ago. Anyway, I'm wondering how you know that you are burning the coal efficiently. I have about an inch of ash on the grate before it drops to the pan. Is that correct? As far as the flame goes, should it be contained in the triangle area. I have flames that are going up outside of that area. Am I feeding too much coal? The manual is not very good in showing the proper burn. I have a stove thermometer on the side of the stove and I am staying around 350-400*. Does that sound right?
I am new to this forum but I have learned a lot from searching other post. Thanks in advance for any help you can offer.

Well I hope you were wearing a ski mask when you bought that stove cause you stole it!

Yes you should never have burning coal dumping off of the grate. Whether or not you are adjusted properly for current conditions is another matter. I assume you have a thermostat installed off of the controller? If you are meeting your setting, great. You may not need to be pushing as much coal as you are currently. My boiler uses the exact stoker your stove does. Right now, I only have about 2"-3" of burning coal on my grate and several inches of ash at the end. You might try backing it down some. It's a balancing act. You don't want to burn more than you need to obviously. Remember that as you make changes in any settings, be patient as it takes some time to show up in your results unlike wood.

Your maintenance settings may also need to be tweeked. Time on and time between cycles. Lots to read here on the forum about your stove. Drink it up.

Welcome to the forum.....Awesome deal you got there!!!

About an inch of ash sounds right.

I usually measure temps on the side of the stove compared to the flue temp measured with a temp probe like used on a bar-b-q grill. If the flue temp is close to the stove temp then you are sending heat up the chimney and could improve your efficiency. I have a barometric damper to help with this.

Look at the ash pan to see if you have a lot unburned coal. You will have some, more if the stove is in "idle" mode a lot; less during the colder months when the stove is running frequently.

The most important parameter for efficient coal burning is the chimney draft. If the draft is too strong, much of your heat
[burning coal] is going up the chimney.

Buy or borrow a manometer and measure your chimney draft, install a barometric damper to control the draft
in windy, or very cold weather, this will keep the heat in the stove, where it can get into your house, instead
of it going up your chimney.

With your grate covered with burning coal to 1" of the edge, this is near full heat, and we haven't had winter temperatures
yet, so I think you have some adjusting and tweaking to do. Right now i'd think a bit less than half the grate covered
with burning coal would be about right. This of course depends on your home's location, size and degree of insulation and
sealing against cold air infiltration.

That was a great deal on a good stove.

Greg L

thanks for the replies. I have very little unburned coal in the ashes. I am running it continuous right now to heat up the basement. I am hoping that once I get the basement heated up the heat will travel upstairs. I am hoping to heat the entire house without having to use the duct option on the stove.

I have the restrictor plate on the combustion blower almost closed and I am still getting pretty high flames. Is that normal?

Greg, It throttled it back some and I have more ash on the grates now. Right now, I am feeding one dot. I have a barometric damper installed and it seems to be working. It is a field controls with the automatic draft control. I have it set at .04. The stack temp with the magnetic stove temp was around 175. The temp on the side of the stove is around 375.

It sounds like you are very close on your settings. The temp differential sounds good to me between stack and stove.

Everyone's setup has its own personality so it won't be exact from install to install. You will probably tweak the timer settings a little on the controller to dial in your preference for the length of pilot burn times and the length of time between pilot burns.

My restrictor plate is about 1/4 open, really cold weather I opened it to 1/3 but never more than that. A manometer will allow you to more accurately set the baro weight. I don't go by the numbers on the baro, but the reading on the manometer when setting the counterbalance weight.

Make sure that your fire doesn't get too far back when in pilot mode. You don't want it to burn back into the hopper or get fumes heading out the hopper. That is where adjusting the pilot timer settings comes in.

Get a few CO detectors. The kind with the digital display are ideal. Date them with a sharpie when you install them and replace about every 5 years. I would get an additional one in about 3 years and then all won't be getting to their end of life at the same time and you can rotate in new ones.

kirtdog wrote:I picked up a used Harman magnum (not a super) for $650 and so far I love it. I replaced a Jensen wood furnace with this and I must say that I wish I would have switched to coal years ago. Anyway, I'm wondering how you know that you are burning the coal efficiently. I have about an inch of ash on the grate before it drops to the pan. Is that correct? As far as the flame goes, should it be contained in the triangle area. I have flames that are going up outside of that area. Am I feeding too much coal? The manual is not very good in showing the proper burn. I have a stove thermometer on the side of the stove and I am staying around 350-400*. Does that sound right?
I am new to this forum but I have learned a lot from searching other post. Thanks in advance for any help you can offer.

here is the manual in pdf for that stove if you need any info there is a lot of post on here or I maybe able to help out I'm burning on also
a couple of thing to check is on the combustion blower that it has the restricter plate on it and its set I run my combustion blower 24 /7 better burn and it helps keep the grates from warping on the control box picture you can also see how I set up my restricter plate,

**Broken Link(s) Removed**

I have another question. I am not getting enough heat on the opposite side of the house from the magnum. I know it is an air flow problem. My question is this, can I tap in to the existing cold air return that is connected to my oil furnace (forced air) and run a pipe down? I figure since the registers are already there that I could use them. Any thoughts???

kirtdog wrote:I have another question. I am not getting enough heat on the opposite side of the house from the magnum. I know it is an air flow problem. My question is this, can I tap in to the existing cold air return that is connected to my oil furnace (forced air) and run a pipe down? I figure since the registers are already there that I could use them. Any thoughts???

on top of the stove there is a plate you can remove (page 26 of manual) and put heating duct into the heat side of the forced air and use the fan on the forced air system like you would use it on the oil system

RayJay,

I thought about that but I don't have control of the fans on my forced air system and the distribution blower on the magnum is not strong enough to push the air throughout the house. That is why I was trying to use natural airflow. I thought if I could connect to the existing cold air return but just have a pipe coming down to the floor of the basement, that would create the circulation that I need without cutting holes in the floor.

you can add in line duct fans to help push the heat out and there has to be a way to use the oil burner fan also

like this

http://www.grainger.com/product/TJERNLUND-Duct-Booster-5C963

Since it looks like your stoker is in the basement, what I would try first is taking the return line from the farthest room and arranging that return line to the basement floor. If your return vent for that room is on the floor then the cool air from that room drops through that return vent to the basement floor pulling warmer air into the room. If you cannot do that with a return, maybe you can do it with a supply vent instead.

titleist1 wrote:Since it looks like your stoker is in the basement, what I would try first is taking the return line from the farthest room and arranging that return line to the basement floor. If your return vent for that room is on the floor then the cool air from that room drops through that return vent to the basement floor pulling warmer air into the room. If you cannot do that with a return, maybe you can do it with a supply vent instead.

THIS is what works. It is very difficult to force air into a room or into an end of a house. BUT if you pull air from a room, or from the end of your house, warm air will replace the air you removed. This works.

Greg L

Realize of course that you are asking alot from a stove in the basement to heat your entire first level. After you've got your feet wet with this mag for a season or two, consider a boiler with a water to air heat exchanger in your duct work. All the benefits of burning coal you enjoy now plus even comfort throughout your home.

Thanks for all of the replies. I am still trying to figure out how to make this work. I am actually considering selling it and getting something else. I was initially going to get a DS machine hand fired but I let a friend talk me into this one and seeing that it was such a good deal, I decided to try it out. I wonder if I will still have the same issues with a hand fired? One of the stove shops wanted to sell me a koker. Apparently, it can connect directly to my existing ductwork. I don't want to give up on this thing but winter is approaching quickly.