Harman DVC-500 Efficiency

Re: Harman DVC-500 Efficiency

PostBy: 009to090 On: Wed Sep 16, 2009 3:32 pm

DVC500 at last wrote:...
Ash was rather high, I think. 17# with most of that wieght from bone. (is this normal???)
Completely white ash, but lots of bone.

Around April/May '09, I figured out why the ash content was so heavy. Normally, coal gets pushed from the bottom of the bin, to the bottom of the burn pot. Between the back sides of the pot and the front of the firebrick on both sides, are two 3/4" cracks or open spaces. Some(alot) of unburnt coal was falling out of the crack and down into the ash bucket before it ever reached the burnpot! :shock:
So I decided to take some accurate measurements of those open cracks, and see if I could cut some firebrick to fill them up. As it turned out, it was easy to cut the firebrick with my wet tile saw, and a 5" grinder. The two pieces of firebrick are held in place by Furnace Cement. Before I installed the pieces, I covered the burn pot with tin foil to prevent the furnace cement from sticking to it. Once the furnace cement was dry, I pulled the brick back out and put them in the oven to cure the cement, and I removed the tin foil at this time.
Note from the pictures below, I had previously 'glued' all three firebricks together, as the two bricks on the outside kept falling off the ledge in the stove. So now, all three firebricks and the two pieces to fill the cracks, are all one piece, glued together with Furnace Cement. FYI... this large solid piece of brick is still completely removeable from the stove, for easy cleaning.
I will re-test the stove for efficientcy, with the same coal I used previously. I'll post the results in this thread.
Attachments
DVC-500 Mod for Large Crack.wmv
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[nepafile=14040]DVC-500 Mod for Large Crack.wmv[/nepafile]
009to090
 
Stoker Coal Boiler: EFM 520 HighBoy
Hot Air Coal Stoker Stove: DVC-500 x 2
Coal Size/Type: Anthracite Rice

Re: Harman DVC-500 Efficiency

PostBy: steveyrock On: Wed Sep 16, 2009 5:53 pm

WoW those are some big gaps.Mine were only 1/4 of an inch and were leaking fine material maybe 1/8 inch bits of coal.I can understand your approach to solving the problem,good work. That coal leaking even though a small amount,drove me nuts too.I simply glued two stainless shims up those cracks with 2000 degree gasket cement.I wonder why your gaps are that big ? Stoves must have different dimensions in that area.I could not even get a pinky tip in mine.
steveyrock
 

Re: Harman DVC-500 Efficiency

PostBy: 009to090 On: Fri Sep 18, 2009 7:45 pm

Just fired it up for the first time this year. I needed to burn off the LPS-3 and see if my Mod worked ok. Its working great! :clap: It got hot in here, and I had to open the windows, but I'm not puttng it out. Gonna be chilly tonite, I bet we have the bedroom windos open :D
009to090
 
Stoker Coal Boiler: EFM 520 HighBoy
Hot Air Coal Stoker Stove: DVC-500 x 2
Coal Size/Type: Anthracite Rice

Visit Lehigh Anthracite

Re: Harman DVC-500 Efficiency

PostBy: sterling40man On: Fri Sep 18, 2009 8:44 pm

Great job Chris!! Nothing wrong with opening the windowstats every now and then!! :lol:
sterling40man
 
Stoker Coal Boiler: Keystoker K6
Stove/Furnace Make: Keystoker
Stove/Furnace Model: KA-6

Re: Harman DVC-500 Efficiency

PostBy: RMA On: Fri Sep 18, 2009 10:19 pm

Nice catch Chris...
Looks like Harman "Engineered" a flaw into the stoker.

Now when you measure the difference in residual ash and compare it to your earlier result, you can assess the increase in efficiency. Translate the difference in efficiency into percentage and dollars saved. :mrgreen: Then apply for a patent on the improvement and sell it to Harman... :devil: (You might also see if a steel weldment might accomplish the same result to cover your patent interests) :flex:

Again nice work,

Bob
RMA
 

Re: Harman DVC-500 Efficiency

PostBy: 009to090 On: Mon Oct 05, 2009 12:27 am

After my last mod, I tested another hopper's full of coal.
Burned 95# of Deep-mined. Size was slightly larger than the Blaschak rice.
Stove Temp used. Set to 1 1/2.
Feed rate set to 1.
Stove Temp set to High.
stove burned, unattended, for 84 hours before going out. Thats 3 1/2 days!
BTU's produced was guesstimated at 12,000/hr. (based on the fact that the minimum setting for the DVC-500 is 7000 BTU/hr. I ran it 1/2 point above minimum, but the blue Ladies were much taller than with the Blaschak Rice. Maybe because if the size difference.
Ash was Pink in color. A mix of red & white. 11 lbs in Ash Bucket.

This new coal appears to have more BTUs than the Blaschak I got, although it is slightly larger than Rice, it still works great.

I still have to test a hopper-full of Blaschak, so I can compare how much coal my Mod is saving, with my second test in this thread.
Last edited by 009to090 on Mon Oct 05, 2009 7:49 am, edited 1 time in total.
009to090
 
Stoker Coal Boiler: EFM 520 HighBoy
Hot Air Coal Stoker Stove: DVC-500 x 2
Coal Size/Type: Anthracite Rice

Re: Harman DVC-500 Efficiency

PostBy: JB Sparks On: Mon Oct 05, 2009 6:21 am

Hey Chris, I missed this thread when you started it last Feb. Just watched your slide show. Good catch of the problem and a good fix. You get three "ata boys" for your good work. :clap: :clap: :clap: :up: :up: :up:
JB Sparks
 
Stove/Furnace Make: Harman - Chubby
Stove/Furnace Model: Harman: SF160 - Chubby Sr.

Re: Harman DVC-500 Efficiency

PostBy: 009to090 On: Mon Oct 05, 2009 8:01 am

JB Sparks wrote:Hey Chris, I missed this thread when you started it last Feb. Just watched your slide show. Good catch of the problem and a good fix. You get three "ata boys" for your good work. :clap: :clap: :clap: :up: :up: :up:

Wow! Three ata-boys! Thanks Jeff. Yep, theres room for improvement in just about everything, its just up to us to find it. :idea: :D
009to090
 
Stoker Coal Boiler: EFM 520 HighBoy
Hot Air Coal Stoker Stove: DVC-500 x 2
Coal Size/Type: Anthracite Rice

Re: Harman DVC-500 Efficiency

PostBy: JB Sparks On: Mon Oct 05, 2009 11:29 am

Hey Chris, Just finished up unloading the last ton of coal. Got 4 tons stacked out back, that should do me for the season.
The man gave me 10.00 back on each ton, said that was a good order. So that means I only paid 265.00 a ton bagged/picked up. I figure I did ok for being up here in Mass.
JB Sparks
 
Stove/Furnace Make: Harman - Chubby
Stove/Furnace Model: Harman: SF160 - Chubby Sr.

Re: Harman DVC-500 Efficiency

PostBy: jrn8265 On: Mon Oct 05, 2009 12:20 pm

How did the LPS3 burn off? Lot's of smoke? Thanks!
jrn8265
 
Stove/Furnace Make: Keystoker Koker
Stove/Furnace Model: Koker 160

Re: Harman DVC-500 Efficiency

PostBy: 009to090 On: Mon Oct 05, 2009 2:00 pm

jrn8265 wrote:How did the LPS3 burn off? Lot's of smoke? Thanks!

No smoke noticed at all. and no smells. The interior just appeared to "Dry out". I did have to scrub the LPS3 out of the hopper, though, cuz the coal was having difficulty sliding down to the pusher-bar. I used a dry Scotchbrite pad inside the hopper, and the wax from the LPS3 just peeled right off. The hopper is as shiney-new as the day I got it. It must be SS.
009to090
 
Stoker Coal Boiler: EFM 520 HighBoy
Hot Air Coal Stoker Stove: DVC-500 x 2
Coal Size/Type: Anthracite Rice

Re: Harman DVC-500 Efficiency

PostBy: kevin63392003 On: Wed Oct 07, 2009 8:18 am

DVC500 at last wrote:
CoalBin wrote:Oh Oh ! That is exactly how mine was, label down

If you look at the round face of the motor , maybe 1/2 to 3/4 from the center is a little oblong hole. If you look into that hole, you can barely make out the felt. The hole should be facing up.

Mark



Mark,
I just got my blower motor turned 180 degrees, and reassembled. Fired the stove back up, and i swear the blower is quieter now! The blower is working fine, I just don't hear sheet metal rattles anymore. I guess the bolts were not tight enough to begin with.
Thanks for the tip!

Chris F.


I inspected my blower last night. Sure enough mine was mounted upside down. I find it hard to believe that Harman is putting all of these together wrong. Is their QA/QC that bad? In any case, i took it apart, oiled it, and rotated it 180.
kevin63392003
 
Stove/Furnace Make: Harman
Stove/Furnace Model: DVC-500

Re: Harman DVC-500 Efficiency

PostBy: kevin63392003 On: Wed Oct 07, 2009 2:56 pm

Does the DVC operate more efficiently with the distribution blower set at high? For example, suppose you're in room temp mode and the thermostat is set at 70 and the ambient room temperature is 65. Wouldn't the DVC have to burn more coal to get to 70 degrees is you have the room temp selector at “low” rather than at “high?” In my mind, it appears that the stove would have to burn more coal to bring the temperature up since the distribution blower isn’t putting as much heat into the room on the low setting. What do you guys think?
kevin63392003
 
Stove/Furnace Make: Harman
Stove/Furnace Model: DVC-500

Re: Harman DVC-500 Efficiency

PostBy: 009to090 On: Wed Oct 07, 2009 3:06 pm

kevin63392003 wrote:Does the DVC operate more efficiently with the distribution blower set at high? For example, suppose you're in room temp mode and the thermostat is set at 70 and the ambient room temperature is 65. Wouldn't the DVC have to burn more coal to get to 70 degrees is you have the room temp selector at “low” rather than at “high?” In my mind, it appears that the stove would have to burn more coal to bring the temperature up since the distribution blower isn’t putting as much heat into the room on the low setting. What do you guys think?

Even at idle, lowest setting for the stove, it is pumping out a 7000 BTUs/hr. Thats more tha enuf to raise the temp of the lower level of my house, up past 75F. I just leave the Distribution Fan's LOW/HIGH setting on HIGH all the time, so the hot air gets more evenly spread out.
009to090
 
Stoker Coal Boiler: EFM 520 HighBoy
Hot Air Coal Stoker Stove: DVC-500 x 2
Coal Size/Type: Anthracite Rice

Re: Harman DVC-500 Efficiency

PostBy: kevin63392003 On: Thu Oct 08, 2009 3:22 pm

I have no doubt that it would indeed raise the temperature to the desired level with a low fan setting. I'm just curious if it would have to burn more coal to do it. If it did, then running your distribution blower on high would be the most efficient way to burn.
kevin63392003
 
Stove/Furnace Make: Harman
Stove/Furnace Model: DVC-500

Visit Lehigh Anthracite