Short Burn Times with EBW-100

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SIERRADMAX

Feeling the Heat
Jan 13, 2011
300
RI
I've had my Econoburn up and running for a month now. It's heating a 2600 S.F. 2 zone house built in 2002 so construction is fairly tight. I know there's a learning curve but I can't seem to get more than 5 hours of burn time on an average 20-30 degF night. Last night's outside average was 0 degF and I don't think it burned for more than 3 hours with a fully loaded stove.

What are some pointers to increase burn times? I'm burning 2 year seasoned oak, maple & willow and have been sporadically checking it's moisture content.

Could the stove be too small?
 
Are you utilizing thermal storage?
 
What was your heat loss calc on your home or how much fossil fuel did it burn on a 0F day previously? E100 sounds like about 75% the size of my eko 40 which is 135kbtu. The rated btu is usually only for optimum wood, etc. and most here figure 75-80% is more realistic. Since you burn some oak 80kbtu per hour should be the output which sounds high for a new home like yours. Are the outer walls 2x6? How much insulation? What kindof windows? I get about 6 hrs on a good load of elm and some wetter oak on a 0F day with my combustion fan at 50% and not much ldling. I'm not weighing but I'm guessing this is about 80kbtu per hour heating a larger home plus a 30x60 shed.
 
Do you have underground lines? Hopefully not, because if you do I bet that's where the heat is going.
 
Are you utilizing thermal storage?
No storage
do you know what your stack temps are? The heat has to be going somewhere.....and it seems like 100kbtu should be plenty for your house.
Flue thermometer has been on the "to purchase list" so I can't comment on flue temps.
Silly question....is your house warm for 24 hours from that burn or just for those few hours?
From a feeding at 11pm last night, I awoke at 3:20am to my thermostats calling for heat. T-stats set to 68 and both zones were reading 66. I walked downstairs and heard the oil boiler fire. Aquastat on wood boiler supply (set to break on rise @ 130degF) must have closed contacts to TT for oil boiler just as I walked downstairs. Setpoint on the econoburn was 188, water temp was 144. Opened the upper door, not a single amber color coal left to reload.
Do you have underground lines? Hopefully not, because if you do I bet that's where the heat is going.
No underground. This is an indoor unit.
 
What was your heat loss calc on your home or how much fossil fuel did it burn on a 0F day previously? E100 sounds like about 75% the size of my eko 40 which is 135kbtu. The rated btu is usually only for optimum wood, etc. and most here figure 75-80% is more realistic. Since you burn some oak 80kbtu per hour should be the output which sounds high for a new home like yours. Are the outer walls 2x6? How much insulation? What kindof windows? I get about 6 hrs on a good load of elm and some wetter oak on a 0F day with my combustion fan at 50% and not much ldling. I'm not weighing but I'm guessing this is about 80kbtu per hour heating a larger home plus a 30x60 shed.

If I remember, I did a heat loss calc and it amounted to around 45,000 BTU w/ 2x4 outer walls, vinyl windows.
 
How did you heat your home before the wood boiler? How many btu's is your oil boiler? And will it heat the house on it's own? How much fule in a yrs time?

I have burn times of 3 1/2 to 4 hours on a 30 degree night, but that also charges my storage enough for 24 hours of heat. I have an 1800sq/ft, 2 story house. R-19 walls R-30 ceilings. Plus family of 5 for DHW. So it seems you got something odd going on there.

Have you contacted Econoburn?
A stack temp would be nice.

How seasoned is your wood?
 
If I remember, I did a heat loss calc and it amounted to around 45,000 BTU w/ 2x4 outer walls, vinyl windows.

Sounds like you should be getting more like 6 hrs instead of 3 if that 45 is correct. How much of the time is it idling on a 0F day? How much insulation in the attic?
 
How is the heat dispersed in your house? Baseboard? Forced air? Radiant?
 
I heat the same sq ft with my 200. The first year I did not have storage. I rarely filled it past the bottom of the door opening. It would run for 12 hours easy idling on and off. But it had extra capacity to do that. I could see if yours is running fan on most of the time it would consume wood pretty fast.

If I run my 200 to storage with 3/4 full of wood it will be done in less about 3 hours.

gg
 
Sorry if you have posted info about your set up before. Do you have a baro damper? Any idea what your draft reading is?
 
If you have a tall chimney and no BD, it could be pulling the heat out of the boiler, so you need to get that flue therm installed to find out about that. But the wood is always the usual suspect. You said a mix of Oak, Maple, and WIllow. What's the rough percentage of each? Willow is a second cousin of cardboard, so if you're using lots of that, the whole thing is explained right there. 2 year old Maple should be very good under any circumstances, but the oak may be a problem, depending on the size of your splits. Have you been re-splitting the larger oak splits down the middle and testing the inside surfaces with a MM? If so, what are those readings? Is your wood staged inside, or do you bring it in and load directly from outside the house?
 
Sorry if you have posted info about your set up before. Do you have a baro damper? Any idea what your draft reading is?


Echo this. Draft needs to be in spec in all conditions - cold weather & wind can raise it quite a bit over baseline. A baro will smooth it out & get it right.
 
Call Dale at Econoburn. He will have you program your control to best suit your needs. Storage is awesome and I advise you get it. When you have a gasser, I wouldn't hesitate putting at least 500gal of storage in. I burn for 3-4 hrs and get enough heat in storage to get me through to the next day. House specs are similar to yours. I would put 1000gal in if I could do it over but 500 gets me by here in northwestern PA
 
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I've had my Econoburn up and running for a month now. It's heating a 2600 S.F. 2 zone house built in 2002 so construction is fairly tight. I know there's a learning curve but I can't seem to get more than 5 hours of burn time on an average 20-30 degF night. Last night's outside average was 0 degF and I don't think it burned for more than 3 hours with a fully loaded stove.

What are some pointers to increase burn times? I'm burning 2 year seasoned oak, maple & willow and have been sporadically checking it's moisture content.

Could the stove be too small?
I too have a Econoburn 100 with no storage , in basement installation (4 years now) If I load mine right up , I can get a 8-9 hour burn thru the night in upstate New York . This would be with 3 out of my 5 zones turned up to 72 degrees in a 1700 sq ft log house. Bruce
 
How did you heat your home before the wood boiler? How many btu's is your oil boiler? And will it heat the house on it's own? How much fule in a yrs time?

I have burn times of 3 1/2 to 4 hours on a 30 degree night, but that also charges my storage enough for 24 hours of heat. I have an 1800sq/ft, 2 story house. R-19 walls R-30 ceilings. Plus family of 5 for DHW. So it seems you got something odd going on there.

Have you contacted Econoburn?
A stack temp would be nice.

How seasoned is your wood?

I've kept track of my oil usage (and price :mad:) throughout the past 3 years. It's probably not reflective of this current year because it's the first year keeping the thermostats higher than 63 in the house due to having a baby. However, the house on average consumed 700 gallons of heating oil between November & March, 300 gallons during April-October to heat an indirect and the occasionally chilly nights. Doing the math, 700 gallons equates to 140 gal./mo.or approx. 5 gal./day times 140,000 BTU/Gallon = 30,000 BTU/24 hr. +/-. So, my 45,000 btu calculation isn't too far off.

My house has r-19 walls, r-30 ceilings (2nd floor) and 2 layers of R-13 in the joists (R-13 was free!). I have not contacted econoburn yet. A stove pipe thermometer is on order. Wood is 2 year seasoned.
How is the heat dispersed in your house? Baseboard? Forced air? Radiant?
Forced hot air controlled by Wifi thermostats & hydro-air fan control units. I have both hydro air units dialed in pretty well and can monitor cycling which has been roughly 4 cycles per hour.
Sorry if you have posted info about your set up before. Do you have a baro damper? Any idea what your draft reading is?
Here's where I'm a little concerned and have been reading alot of information from other posts. Bottom line is no, I don't have a B.D. and my chimney is a tall one... 35'+, entirely on the outside. I was fighting a downdraft problem (when not in use) to where the damper was pointing into the room. The chimney shares 3 flues, of which the other two are for the oil boiler & a woodstove on the first floor. At the time, I would get a heavy smoke odor emitting from the B.D. whenever the woodstove was operating. So, I have the B.D. covered. I've seen many other WB users post their use w/o one so perhaps I have to find a way to make one work with my situation.
If you have a tall chimney and no BD, it could be pulling the heat out of the boiler, so you need to get that flue therm installed to find out about that. But the wood is always the usual suspect. You said a mix of Oak, Maple, and WIllow. What's the rough percentage of each? Willow is a second cousin of cardboard, so if you're using lots of that, the whole thing is explained right there. 2 year old Maple should be very good under any circumstances, but the oak may be a problem, depending on the size of your splits. Have you been re-splitting the larger oak splits down the middle and testing the inside surfaces with a MM? If so, what are those readings? Is your wood staged inside, or do you bring it in and load directly from outside the house?
Very few sticks of willow. This is normally my "starter wood". Wood is brought in via tractor or bobcat bucket and stacked on a wood rack (1 face cord) in the basement.

My approach is to get a stovepipe thermometer and a manometer. Monitor the temps and draft during gasification & idle. I have a feeling based off the comments that most of my heat is being sucked out the chimney because of the lack of a B.D. I'll post my findings.
 
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What does the EB spec for chimney draft?

For a bit of a rough idea, I have about 30' of chimney (7" insulated stainless, inside the house), on an open hilltop, and it pulls 0.1" normally when burning (mine specs 0.08" for the natural draft operation). That's with no effort to seal my pipe joints. If I hold my BD closed when the wind is blowing and there's a fire going, it can jump up to 0.3". So I suspect you're seeing more draft than you should be.

The backdraft puzzles me though. What did you mean by 'to where the damper was pointing into the room'?
 
What does the EB spec for chimney draft?

For a bit of a rough idea, I have about 30' of chimney (7" insulated stainless, inside the house), on an open hilltop, and it pulls 0.1" normally when burning (mine specs 0.08" for the natural draft operation). That's with no effort to seal my pipe joints. If I hold my BD closed when the wind is blowing and there's a fire going, it can jump up to 0.3". So I suspect you're seeing more draft than you should be.

The backdraft puzzles me though. What did you mean by 'to where the damper was pointing into the room'?
On a cold chimney, top of the damper is pointing into the stovepipe and the bottom is pointing into the room. There's a stop to prevent it to go much further but it's noticeably pointing into the room.
 
That means it is pulling draft up the chimney like a freight train - just the opposite of what I'd call a back draft.

I'd say it definitely sounds like you've got way too much draft going on & the baro is a necessity.

Not sure why the smoke smell when the stove is going - unless somehow the EB chimney is pulling fumes out of the stove air inlets, down into the basement, then up the chimney? How tight is the stove room?
 
On a cold chimney, top of the damper is pointing into the stovepipe and the bottom is pointing into the room. There's a stop to prevent it to go much further but it's noticeably pointing into the room.
That's weird! Mine is hanging straight up/down when I'm not burning/cold chimney. Maybe you could just cover it up when you are not burning.
With a chimney that tall, I can almost garantee that using a properly set BD will improve burn time drastically!

Edit: Ah. I see, your chimney is drafting just from the warm air it is pulling out of the house when you are not burning. I wonder if the smoke smell is just coming from your boiler firebox?
 
That means it is pulling draft up the chimney like a freight train - just the opposite of what I'd call a back draft.

I'd say it definitely sounds like you've got way too much draft going on & the baro is a necessity.

Not sure why the smoke smell when the stove is going - unless somehow the EB chimney is pulling fumes out of the stove air inlets, down into the basement, then up the chimney? How tight is the stove room?

This is the type of damper I have. When the chimney is cold and a piece of paper is held against, it is blowing away from the damper resulting in a heavy downdraft.
http://www.fieldcontrols.com/rc.php
 
My baro goes like that when it's windy and I'm burning. I happen to have a basement window like 3 feet from it, I just leave it open a tiny crack. That ensures that the air the chimney is pulling up from the basement & the house is coming from outdoors rather than other parts of the house - and is mostly cold outside air rather than heated house air.
 
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