Harman DVC-500 - condensation on hopper lid?

Hi -

Do those of you who own a DVC-500 get condensation on your hopper lid now & then? I searched this forum to see any posts about condensation and they all say this is because poor draft / needing a baro damper, etc. But with the DVC-500 being an airtight unit, I don't think those reasons apply, do they?

Do you get condensation on your hopper lid? We've been burning the stove for 3 weeks now so I want to ask to be sure we aren't wrecking our stove in its first season.

Thanks.

I have been burning my dvc for 5 weeks. No condensation on hopper lid. Stove woks great. Only use room temp. mode
keeps house downstairs at 72.

Is your coal damp at all when you load it? Or is it completely dry?

Jerry at LL says that condensation on the inside of the hopper lid is a sign of poor draft. Not sure it's the same for a Harman.

The unit could draw air from the hopper, maybe too much draft or not enough...or fumes getting back up into the hopper.

Have you checked your draft?

My hopper gets condensation sometimes as well. I soak it up with a paper towel. Other than somehow drying out the coal, there is not much you can do. The DVC is a direct vent stove & is a closed system. There is a pressure sensor which checks to make sure the stove burn chamber is running at a negative pressure. (The stove controller runs the exhaust blower a bit stronger than the combustion blower - there is no draft, the stove creates the burn environment & the venting) Leaving the hopper lid open or putting holes into it would cause the stove safety to trip. The hopper lid is essentially at the top of a sealed container, putting cold, damp coal into it then heating it up will cause condensation. This is my second season like this - no rust in the hopper, most of it is SS.

It would be interesting to see what Harman thinks about the condensation, because they warn you not to put wet coal into the stove....

CoalBin wrote:My hopper gets condensation sometimes as well. I soak it up with a paper towel. Other than somehow drying out the coal, there is not much you can do. The DVC is a direct vent stove & is a closed system. There is a pressure sensor which checks to make sure the stove burn chamber is running at a negative pressure. (The stove controller runs the exhaust blower a bit stronger than the combustion blower - there is no draft, the stove creates the burn environment & the venting) Leaving the hopper lid open or putting holes into it would cause the stove safety to trip. The hopper lid is essentially at the top of a sealed container, putting cold, damp coal into it then heating it up will cause condensation. This is my second season like this - no rust in the hopper, most of it is SS.

It would be interesting to see what Harman thinks about the condensation, because they warn you not to put wet coal into the stove....

Yes, that's what we've been doing -- just opening the lid every once in a while to check, and drying it off if it's there. OK, I'm relieved to know we're not the only DVC-500 owners who see this.

I guess it's like putting a Rubbermaid container in the microwave without popping the top, and reheating something. But popping the top on the hopper is a no-no, so if the coal's damp then condensation can happen.

OK - thanks for your help!!!

IMO a hopper should never have condensation, you will rust it out in no time, even stainless doesn't like nitric acid so much. I would talk with your dealer and figure out what is causing it and get it to stop.

As stated previously in the non DV stoves this is a sign of poor draft, for the DV Harman it could be wet coal or something else. If it where me I would find out why and get it to stop.

My coal is stored in a coal bin under my front porch. It is dry but cold. I sometimes load directly into hopper, no condensation. Most of the time I fill 5 gallon pails, bring it into my basement and load into stove when needed.
I have found that the dvc requires very little work, had no problems at all since burning the stove. I run the stove
all the time on the temperature setting mode 72 degrees and only load and take out ashes.
The dvc draws in cold air from outside for combustion, maybe that could be your cause of moisture in hopper.

I think you will find the only way to stop the condensation is to use bone dry coal. The dvc is the only stove of its kind and being airtight the moisture in the coal has no where to go when it becomes warm in the hopper. You could put the coal bucket near the stove for a while before filling to help dry it out however it will make some dust when you fill the hopper. Matthaus is right the condensation will end up rusting out the hopper after only a few years, unless they are using 316L stainless which I highly doubt do to the very high cost.