Harman "E" CW30, the only EPA wood/coal combo stove ever made...

There seems to be a general misconception that combination coal and wood stoves can't burn wood cleanly or efficiently. Generally that has been the case, but there was one combo stove made that did both very well and achieved EPA status, the Harman "E" CW30. In another thread there seems to be some interest in learning more about this stove. I didn't want to get off topic in the other thread, so I thought I'd start a new one about this stove. Unfortunately, Harman stopped making this great little stove, but the engineering is still interesting...
Here is the original thread:
http://www.hearth.com/econtent/index.php/forums/viewthread/20970/



[quote author="BeGreen" date="1217918329"]Great find. Front, back, top and interior views would be great. I am particularly interested how they manage the air flow and options provided for top (wood) or bottom (coal) burning. Is there a removable grate system for the coal?[/quote]

There is no removable grate system, everything sits on the shakers.

The stove has two doors in the front. The traditional larger front loading door and then a smaller door below it which houses the ash pan and the lever that controls the air flow. This lever at one extreme controls the air flow for coal ("C") and wood ("W") at the other. The lever sticks through the lower ash pan door and can only be set to the either wood or coal with the door closed as there is a piece of metal cast into the door which blocks the lever from mistakenly or accidentally being pushed over to the wrong position. You simply slide the lever one way or the other to adjust the airflow for the selected fuel, much like you would for a traditional stove. As you slide this lever, it opens or chokes down the air flow either going into an air path that leads under the shakers for coal fuel, or upwards across the main loading door while burning wood.

There is also a damper at the top of the stove which bypasses the secondary combustion while burning wood. You open this damper for starting the fire, when reloading the stove, or while burning coal.

When you switch from wood over to coal, all you do is open the lower ash pan door, switch the airflow lever from wood to coal, re-close the door, then open the upper damper for burning coal (so it bypasses the secondary combustion path)... it's that simple. You can obviously switch from one fuel and back to the other without the fire ever going out. To shake the ashes while burning wood or coal, you just move the shaker lever on the side of the stove and the fine ash gets disturbed and falls into the ash pan below.

The stove was so cleverly designed, I'm amazed the concept never really took off.

Here are a couple of pages copied from the owners manual which will give you a better idea of what I'm talking about, I'll post actual pictures of the stove in a couple of months when I yank it out of the garage...

I didn't see one listed in the owners manual.

To start a wood fire you l leave the damper open for about 5 to 15 minutes, the lower primary air control is left full open as well. After the fire is well established, the damper gets closed and the primary air gets choked down. When refueling, they both get reopened for about the first 5 minutes.

I just installed a harman cw30, getting alot of black buildup on door. With wood any help thanks

Wet1, based on your insert, the stove makes a lot more sense now. I am curious to the outside primary air connector??? I guess I never looked under the stove...Is there a opening under the stove? Can't wait to get home and look at it again...thanks.

Yes, there's an opening in the bottom (towards the rear) for hooking up an optional outside air feed... I seem to recall it's flush and faces down (although I could be mistaken), so you might have to use an elbow or make a box to connect to it... but it is under there.

Are you using the secondary combustion and getting the stove warm enough?

I'll look...that could be part of my lack of air issue as well...I wasn't using the top damper either.

I open top damper and bottom door when reloading. Then close top damp & bottom door. Seems to me It's firing fine , just issue with glass getting black. What did help some I took out the 3 bars in front of stove , I don't over load with out bars. This is my first year with wood and not primary heat. I have a Gibraltar coal insert in family room, real German tank.

I found the vent on the bottom of the stove...I am going to shop-vac the heck out of it tonight and make a fire. We'll see what happens.

Hello, I recently purchased a Harman E CW 30 from a friend. You are correct that it is a great wood/coal stove. I burn wood in the evening and over night, then I throw coal in it all day while I am at work. When I get home it is back to wood. It works great. I have it in the basement, and it basically heats my whole house. I live in central PA.
I am however having some problems with maintence. As I said I picked it up used this past fall and it is in pretty good shape. As I have burned for the last 3 months however, I am having some metal components inside the fire box deteriorating. There is a large metal crossbar on top that is falling apart. The secondary combustion waffle won’t stay up top and continues to fall down. there are two metal rods that are attached to the metal crossbar that also are in rough shape. I am not even sure what they are used for??? I am going to try to get in touch with Harman and ask about parts.
I really like this stove, and want to keep it runnig well. Any suggestions on parts and or servicing the stove.
thanks
chanlon

Hi Chanlon,

Glad to hear from another very satisfied owner!

I'm not sure exactly which pieces you're referring to, and I'm not home so I can't look in my stove to ID them, but I do know I don't have any deterioration up there in mine since I just completely clean mine from top to bottom not to long ago. If you're handy, I would think it wouldn't be too hard to fabricate the pieces in question yourself. Otherwise, Harman still stocks parts for these stoves... I think I've even seen a parts list with prices referenced on another website... Although I don't recall where I saw it off hand.