We had a defective stove - it's fixed but I have ?'s

We bought a Harman DVC-500 direct vent coal stoker a couple weeks ago, but just finally got it up and running due to a faulty circuit board / temperature probe.

Apparently the temperature probe, that determines if the hopper temperature is too hot, was whacked. It is supposed to indicate when the hopper is too hot, and if so, run the feed motor basically non-stop, to get the coal out of the hopper and into the box - so any fire is in the box and not the hopper. Makes sense, except our probe was saying that it was too hot even when it was not running - so the feed motor was always running. We had a crazy fire the first night and I stayed up all night waiting for it to go out. We shoveled out all of the coal from the hopper and just let it feed everything in to die out.

Anyway - we got a new circuit board put in and still had trouble. Only when the tech put in a new temperature probe did it begin to work properly. So yesterday was our first day of running the stove.

I was nervous in the first place to have a box of fire in my living room, and then with the trouble we had it made me more nervous. Knowing that our stove is fixed, I feel much better and didn't have trouble sleeping last night (first night the stove was on). But I'm still leery of leaving the house with it on.

Were you guys nervous the first time you left the house with your stove on? It's been running for 24 hours now...we've got it figured out (so far) so that it's about 72 in the downstairs and about 67 upstairs (nice!). So it seems to be fine. I guess I just need to get my foot out the door and go for a quick trip somewhere so I get over this initial worry.

Also - I read that a few other people had issues with their Harman DVC-500 from the start. Was your problem the same as my problem? One guy said that his was from a bad year. How would I know if mine was from that year - or if I should anticipate any other problems?

Thanks for your help. I already do love this stove and I know I will love it more when I don't see the Petro man every month with a $600 bill.

I have a comfortable chair next to my boiler in the basement. I almost put a cot down there along with some beef jerky and a mini fridge. I used to check on it every 1/2 hour, now I check it once a day.

The Harmon is a good stove from what I've read. It seems to be more up to date than many of the other stoves on the market. However, there is also more to go wrong as you discovered. From what you write I don't like how your stove handles a hopper fire. I would think that Harmon would use a sensor mounted on the hopper and when it sees a certain temp It would shut down the stove. Instead the feed runs constant and keeps dumping coal on the grate and over fires the stove. I don't like this design. Does the coal eventually overflow the grate and into the ash bin too? In the beginning, I was also very hesitant to leave my stove running but it has proven itself to be safe and reliable. Although, last year I did have a hopper fire after I let the stove run low. I have since added a baro damper on my direct vent and now feel safe that this will not happen again. In fact I tried to force a hopper fire with out any luck. Good luck with the new stove.

This is my second season with my DVC-500 & I love it. When we first installed it - I was a bit leary of leaving the house with the stove running - after the first day, I was sure it was running safely. Now its a friendly warm glow which we miss when away from the house. Treat it like a fridge (almost)

As simple as they are, It takes a while getting used to the controls & how they react, particularly during warm spells. I keep my stove in the basement, & temp probe location makes a big difference in how the stove reacts to outside weather changes. I found in my house, nudging the temp control a bit & patiently waiting for a change is better than big adjustments. If you need a quick blast of heat, switch it over from room temp mode to stove temp for 1/2 hr or so.

I can go one hopper full + one bucket full before emptying the ash. ( I try & empty ash after one hopper - but adding another bucket at night will get you through the night - just tend to it in the morning) I get about 4 days on a hopper with on low, around two days in the deep of winter. Keep an eye on your fire. It should be an evenly progressing line of red - I've had it that a walnut sized chunk of coal blocked part of the feed mechanism.

Hope this helps

traderfjp wrote:From what you write I don't like how your stove handles a hopper fire. I would think that Harmon would use a sensor mounted on the hopper and when it sees a certain temp It would shut down the stove. Instead the feed runs constant and keeps dumping coal on the grate and over fires the stove. I don't like this design. Does the coal eventually overflow the grate and into the ash bin too?

Yes - the coal did overflow into the ash bin. It was very scary for me - I was finally "OK" with getting the coal stove, only to have it go crazy the first time we turned it on. It's fine now - been running almost 48 hours on low yesterday & today.

traderfjp wrote:In the beginning, I was also very hesitant to leave my stove running but it has proven itself to be safe and reliable. Although, last year I did have a hopper fire after I let the stove run low. I have since added a baro damper on my direct vent and now feel safe that this will not happen again. In fact I tried to force a hopper fire with out any luck. Good luck with the new stove.

When you say you did have a hopper fire after letting the stove run on low - why did this happen? Can't you let a stove run on low for extended periods of time? From what you write it makes me nervous - as we've had our stove on low these two days. (By low I mean it's on stove temp 1.5 / feed adjuster 3 for those who have the same controls as me.)

Also - in our instruction book it specifically says to not put a flue damper in the exhaust venting system. But is that what you did? Just curious. I'm still learning.

Tomorrow I have to go to the Y for class so it will be the first time we're all away from home with the stove on. Yikes. I'm more comfortable with it today than I was yesterday but it still taking some adjusting. Once I get over the initial "yikes" I should be more OK!

ErinMarie wrote:
Also - in our instruction book it specifically says to not put a flue damper in the exhaust venting system. But is that what you did? Just curious. I'm still learning.

They may be referring to a manual damper, he's referring to a barometric damper which are commonly used. You may want to reread the instructions or if you have any questions contact the manufacturer to get a clarification.

Installed a dvc-500 in my family room 10 days ago. My gas heat hasn't been on during that period.
The dvc-500 is a great heat source. Takes a while to get used to learning how to monitor the nstove.
During a warm period last week, I set the teperature on 50 and the stove just idled for a day and a half.
More then pleased with dvc, have not had any problems.
I do have a question, on your chimney pipe outside, is the bottom of the chimney left open?
The installer told me that this was a safety feture in case of severe down drafts.
I actually have heat coming out of the bottom of the chomney.
Let me know.

I meant that my hopper was low with coal and also running the stove on low was a bad combination. The stove began pulling air from the hopper and I guess the fire traveled up their too. I came home to hot coals in the hopper - it wasn't fun. I think the worst case scenario is that I would have warped the hopper but that didn't happen so I was lucky. The barometric damper was installed so the stove could pull as much air as is needed from the room and not from the hopper if I run the hopper low again. On a damper the flap oopens up or closes down so the stove gets the air it needs.

TCOAL wrote:During a warm period last week, I set the teperature on 50 and the stove just idled for a day and a half.
More then pleased with dvc, have not had any problems.

Do you use your stove on "room temp" or "stove temp"? We've had ours set on "stove temp" - at a pretty low setting (1.5 stove / 3 feed adjuster) since it's been close to 50 outside the last few days. Is this what you'd all call "idling?"

TCOAL wrote:I do have a question, on your chimney pipe outside, is the bottom of the chimney left open?
The installer told me that this was a safety feture in case of severe down drafts.
I actually have heat coming out of the bottom of the chomney.
Let me know.

I am pretty sure the vent pipe is left open. The pipe outside is shaped like a candy cane (sorry for the girly reference) with the hook part ending at about a 30* angle (from horizontal). I am pretty sure it's open - if I put my hand beneath it it's warm. (It was windy yesterday when I did this so it was not as hot as I expected...but still warm).

Don't try to put a baro damper on a dvc 500 as it is an air tight stove. the bottom of the chimney pipe is open because I believe that is were the stove intakes its combustion air

Erinmarie,go have a drink or two and enjoy the heat, everything is going to be just fine.

BK

During the warm period last week I had my dvc-500 set on the room temperature setting of 50 and the stove just
idled for 2 days. I found that when you use the stove temperature setting on a warm day ( setting the stove temp. to low)
it throws off to much heat. I have never pushed the feed rate past one either. Try this on a warm day it works fine.

curious if the hopper fires mentioned can happen with a Harman Magnum - been running it for 2 years without incident and run 24 hours. I though part of the Harman reliability was the way the coal travels to the burn plates. Since it travel up from the hopper to the insode of the stove this design is supposed to make catching fire impossible

I've been running my new DVC-500 for about two months now. It does take some getting used to. I'm not sure the temp. probe is working correctly...it seems like it will bring the room up to temperature but then it drops down and doesn't come back. Stove temp. works fine though.
A comment about the cleanout T on the bottom of the flue pipe. I had mine open just like it showed in the manual, but the pressurized exhaust was being drawn from the open cleanout cap into the intake vents. I could smell the exhaust in the house and I also noticed that stainless steel around the intake vent was starting to corrode. I spoke with several dealers and the concensus was that it was safe to cap the cleanout, which is what I did. Haven't noticed any problems and it's been on there for at least a month.
One thing troubles me....there is some rust forming inside the hopper . I'm using bagged Blaschak coal and it's pretty wet. I'm hoping it doesn't get worse but I'm afraid it will. The manual recommends this brand so that's what I'm using. Anyone else noticing any corrosion in the hopper?
Nice to be in the forum. I've found much useful information here already.
Nok