Harman DVC-500 Efficiency

I just got done with my first, real-life test of the efficiency of the DVC-500.
Burned 90# of Blaschak rice.
Stove Temp used. Set to 1 1/2.
Feed rate set to 1.
Stove Temp set to High.
stove burned, unattended, for 54 hours before going out.
BTU's produced was guesstimated at 10,000/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.
Ash was rather high, I think. 17# with most of that wieght from bone. (is this normal???)
Completely white ash, but lots of bone. No clinkers.
Outside temp ranged from 30 during the days, to 9F one of the nights (last two days and nights).
Inside temp was 71 to 73F in the lower level of the house (and 68-69F in upper level of house. (3000 Sq. Ft heating area)

Unfortunately, I can't run a similar test, with the stove running flat-out. I tried it, and the lower level QUICKLY got over 100F !!!
I'll have to wait until the outside temp drops below -30F for that test. I am looking forward to it !

I would be glad to hear what other DVC-500 owners are seeing.

Thanks

Chris F.

I would be happy to tell you how my DVC 500 performs, except it's not here yet. My Harman has been on order since May 2008 from SOS Stove in New Jersey.

I have 11.5 tons of coal ready to go. Thankfully oil prices have gone down.

Got rice from reading coal, my brother and I split a trailer load 22.5 tons in bags.
Yes it is wet, he got a large plastic garbage can and set it up on blocks after drilling holes in the bottom. After filling the can with coal the water runs out the holes into a pan under the can and the coal dries out. It works pretty good. Coal was about 206 $ per ton delivered.

Coal Joe wrote:I would be happy to tell you how my DVC 500 performs, except it's not here yet. My Harman has been on order since May 2008 from SOS Stove in New Jersey.

I have 11.5 tons of coal ready to go. Thankfully oil prices have gone down.

Hey Coal_Joe, Your in the same boat I was in. I ordered my DVC-500 on May 1st, 2008, and I picked it up from the dealer (in Flemington) on Jan 21, 2009. I was kicking myself for 8 long months, wondering "Why didn't I buy from SOS". Now it sounds like they had the same issue getting Harman stoves as the Flemington dealer. I wonder if we paid the same price.

Anyway, I am assuming you bought your Baschak from SOS. That is where I got my initial bags of coal too, so you will have the same results as I am seeing. Get ready for LOTS of Ashes and bone. I use it on my driveway. Its covered in ice, and the coal ashes really work good for anti-skid.
FYI, The rice in the bags was VERY wet. Some bags had a gallon of water. SOS leaves the pallets outside, WITHOUT a cover or tarp over them. The DVC-500 hopper did NOT like the wet coal. The wet rice refused to slide down to the pusher bar. I had to spread out the coal on a tarp, to let it dry out first. "Moist" rice was ok, "WET" rice was a no-no.
I just ordered my BULK supply of Blaschak rice from Aerni and Hitzel in Easton. It will be delivered on monday. I have a bin, so I don't need all my coal in bags. $239 a ton, and no delivery charge. It gets cheaper, the more you buy.

Once you get it installed, set your dials to the above settings, and then ONLY change the STOVE-TEMP knob for increasing or decreasing the heat output. I never have to change the feed rate, and I am not using the Room Temp Probe.

Good luck,

Chris F.

DVC500_at_last,

Is that a log home? What was the outside temp during your test?

Thanks,
Jeremy

beatle78 wrote:DVC500_at_last,

Is that a log home? What was the outside temp during your test?

Thanks,
Jeremy

Hi Jeremy,
Not a log home (I wish it was), its a standard 2 x 4 framed house, with ceder shake siding.
Outside temp ranged from 30F during the days, to 9F one of the nights, during my burn test.
Hope this helps.
I'll be adding to this post, since I just got my bulk load of Blaschak, and the rice is MUCH cleaner than the Blaschak in the bags.
More to follow.

Chris F.

DVC500_at_last wrote:

beatle78 wrote:DVC500_at_last,

Is that a log home? What was the outside temp during your test?

Thanks,
Jeremy

Hi Jeremy,
Not a log home (I wish it was), its a standard 2 x 4 framed house, with ceder shake siding.
Outside temp ranged from 30F during the days, to 9F one of the nights, during my burn test.
Hope this helps.
I'll be adding to this post, since I just got my bulk load of Blaschak, and the rice is MUCH cleaner than the Blaschak in the bags.
More to follow.

Chris F.

Woops, missed the temp from post #1

That seems like good usage. My parent hav a 9 or 10 year old DVC-500 and it seems very efficient!! Never had any problems with it.

beatle78 wrote: That seems like good usage. My parent hav a 9 or 10 year old DVC-500 and it seems very efficient!! Never had any problems with it.

Glad to hear your parents DVC-500 is holding up. It has obviously paid for itsself by now. All original fan motors? Thats good to hear.

Chris F.

DVC500_at_last wrote:

beatle78 wrote: That seems like good usage. My parent hav a 9 or 10 year old DVC-500 and it seems very efficient!! Never had any problems with it.

Glad to hear your parents DVC-500 is holding up. It has obviously paid for itsself by now. All original fan motors? Thats good to hear.

Chris F.

yes, everything is all original. The only thing that would have been replaced are the door gaskets.

Speaking of fan motors, I had a problem the other day.

My distribution blower started making sick noises. Then it made no noise at all..... I called the dealer & they started with a song and dance about not having some $#@@% yellow warranty paper on file (they were total robots about this - !!!!) - so I wound up taking the blower motor apart thinking I could relubricate,restart and keep it going long enough to get it replaced.

What I found is something everyone should take a look at. My blower motor (not the blower housing, but the motor itself) was mounted up side down in the housing. When the motor heated up, oil that was in the bearings was able to leak out of the lubrication holes. Over time it ran dry & siezed up. I flipped the motor & soaked the felts with oil - spins like new now.

On my stove, the power cord was coming out towards the back of the stove. When I flipped the motor, the wire faces the stove body & the oiling holes face up. ( I never knew it had oil holes & no where is oiling the motor mentioned in the manual) Now that I know that I can oil it, its getting taken apart, cleaned & re-lubed once a season. I was amazed at how dirty the squirrel cage blades were. BTW-If it goes bad, no big deal, dealer wants $120, Grainger has one in stock for $65.

On the subject of efficiency, I recently covered both sides of the stove with 1" finned aluminum heat sink material ( 12"x15" bolted on under the covers) Closed off the cover bottoms by migging a 1" strip of steel onto them. Mounted some nice mil-spec rotron box fans to the lower face of the covers. More noise - More heat. I'll do a write up after I take some pics.

PS - Feed Rate Adjuster should be left at '3' - by running it at '1' you are just limiting the stove at full blast. In stove temp mode, the stove temp dial sets the feed rate (1-7) To put it another way - Feed Rate Adjuster determines how much ash you have in front of the fire @ "7" which is 100% output. Its factory set at '3' When I dialed mine in, '3' gave me a ~1.75" ash line - so I left it alone at '3' The 'stove temp' dial should really be labeled 'feed rate / room temp'

CoalBin wrote: My blower motor (not the blower housing, but the motor itself) was mounted up side down in the housing.

WOW! Good news CoalBin! Good catch! I'll check mine this morning.

Most of the parts in the back of the DVC-500 are not custom made, and you probably can find several sources for all the motors.

It sounds like you have an with the sides! Too bad we couldn't measure the BTUs on your stove in comparision with the BTUs on a non-modified stove. Is the stove using more electricity now, with the extra fans?

Chris F.

CoalBin wrote:Speaking of fan motors, I had a problem the other day.

My distribution blower started making sick noises. Then it made no noise at all..... My blower motor (not the blower housing, but the motor itself) was mounted up side down in the housing. When the motor heated up, oil that was in the bearings was able to leak out of the lubrication holes. Over time it ran dry & siezed up. I flipped the motor & soaked the felts with oil - spins like new now.

On my stove, the power cord was coming out towards the back of the stove. When I flipped the motor, the wire faces the stove body & the oiling holes face up. ( I never knew it had oil holes & no where is oiling the motor mentioned in the manual) Now that I know that I can oil it, its getting taken apart, cleaned & re-lubed once a season. I was amazed at how dirty the squirrel cage blades were. BTW-If it goes bad, no big deal, dealer wants $120, Grainger has one in stock for $65.

CoalBin,
I just checked my blower motor. Sure enuf, the power cord faces to the rear of the stove. The label on the blower motor faces DOWN. I don't see or feel any oiling holes, do I need to remove the motor from the blower housing to see the oil holes? It looks easy enuf to do.
Thanks,
Chris F.

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.

The fans only draw 15W a side - a heat sink definitely puts off more heat - I compared (by hand) heat rising off the plain side vs heat sinked side (no fan, just heat sink and open bottom side cover) I need to grab some photos & write it up. Was a satisfying little project !

Mark

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

Ohhhhh (insert dirty word here) !
Heres the pic of my blower motor. Sure enough! its upside down! Ok, time to get out the wrenches. At least mine is shut down right now. Its over 60F outside right now.

I would be interested in seeing your pics of your modifications. Might be a nice little project to attempt this summer. My brother is a certified TIG welder, so I'll throw a little work his way.

Chris F.

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 just completed my second, real-life test of the efficiency of the DVC-500.
Burned 95# of Blaschak rice. This time, I used Blaschak rice, bulk delivered, instead of bagged. Bulk delivered Rice was VERY clean, no 'fines', and not wet, only a couple 'lumps' of frozen, which easily crumbled apart when I picked them up.
Stove Temp used. Set to 1 1/2.
Feed rate set to 1.
Stove Temp set to High.
stove burned, unattended, for 71 hours before going out.
BTU's produced was guesstimated at 10,000/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.
Ash was 14#, with some bone and 'crustys', but alot more powder-ash this time. It appears to be a more efficient burn.
Completely white ash. No clinkers.
Outside temp ranged from 40 during the days, to 20F during the nights (last three days and nights).
Inside temp was 72 to 74F in the lower level of the house (and 69-70F in upper level of house. (total 3000 Sq. Ft heating area)

It appears this bulk delivered load of Blaschak rice was more efficient (more BTUs) than my first load of Bagged Blaschak rice. I'm not sure why. Does Blaschak use one breaker or mine for their bagged rice, and another breaker/mine for their bulk rice?
Well, since my bin is completed and in servce, I will be ordering bulk from now on.

Chris F.