EKO 40 OUTPUT?

[weiland13]

Last night I fired up the EKO. I have 500 gallons of storage. My starting temp on the top of the tank as well as the bottom of the tank were 100 degrees. I burned a mix of woods (mostly pine, some birch, some maple, various others) for about 6 hours. This brought my tank upper and lower temps to 170 degrees. The only draw from this tank was 40 gallons of DHW thru a plate exchanger located around 50 feet away in the basement. My flue temps were in the 425-475 degree zone for the bulk of the time. My secondary burn looked great, and the amount of wood seemed to be in line at around 3/4-A full box (I did not weigh it). Does this seem like a long time to get the tank up to temp? I see others heating 1000 gallons in that amount of time. Is there more tweaking to be done or is this in line with other's results. I also have an alpha circ for my storage loop. It was telling me it was circulating 10-12 GPM for much of this time. Most of the time the water exiting the boiler was 170-180 degrees. Thanks in advance for any comments.

 

[Donl]

I too have an EKO 40 and 500 gallon storage. What you are experiencing seems about right to me. Going from 100 degrees up to operating temperatures should be a once a year event. Once at operating temperatures, the temp should not be allowed to drop lower that 130 - 140. A bit lower if you have radiant. I would not go much higher than 1000 gallons with an EKO 40. In my case a 1000 gallon storage would be better.

 

[taxidermist]

Last night I fired up the EKO. I have 500 gallons of storage. My starting temp on the top of the tank as well as the bottom of the tank were 100 degrees. I burned a mix of woods (mostly pine, some birch, some maple, various others) for about 6 hours. This brought my tank upper and lower temps to 170 degrees. The only draw from this tank was 40 gallons of DHW thru a plate exchanger located around 50 feet away in the basement. My flue temps were in the 425-475 degree zone for the bulk of the time. My secondary burn looked great, and the amount of wood seemed to be in line at around 3/4-A full box (I did not weigh it). Does this seem like a long time to get the tank up to temp? I see others heating 1000 gallons in that amount of time. Is there more tweaking to be done or is this in line with other's results. I also have an alpha circ for my storage loop. It was telling me it was circulating 10-12 GPM for much of this time. Most of the time the water exiting the boiler was 170-180 degrees. Thanks in advance for any comments.

Sounds like you are doing fine to me. Your first burns of the year will take longer to heat up your tank.

Rob

 

[weiland13]

It looks like maybe I should be concerned more about burning efficiency vs speed of charging the tank??? Like I said, I just notice some people are able to heat 1000 gallons in nearly the same amount of time. It looks like my actual BTU/Hour output is only around 53000-55000. This is the part that concerns me the most. Am I figuring wrong?

 

[mr.fixit]

I seen this so I fired up the boiler today and noted starting and ending temps.
I also have an EKO 40 with 500 gal storage and shut off all loads other than storage
10:45 am started fire-top of storage was 108* and bottom was 105*
11:00am fully loaded boiler-mostly smaller oak branch wood with 3 or 4 dry oak splits
11:08am nice blue flame in lower chamber,boiler at 163* and stack temp at 300*
11:20 fan speed cut to 60%(started at 90)stack at350*
11:45 went to lunch
2:45 top of storage at 184* and bottom at 170*
3:00 top of storage 183* and bottom at 180* Nice amount of coals left(to bad it's not colder I could reload!)
When my stack temps start going over 400* I clean the HX tubes (fun job)
To me your stack temps seem kinda high but I suppose there is difference in thermometers and location.
BTW Weiland do you have any connection to the trucking co.?

 

[weiland13]

Mr. fixit,
I am distantly related to the trucking company I think. My probe is 1" away from the back of the EKO with a probe that goes just about to the center. The diameter of the Flue is 8". The thermometer is a JLD612 control with a type K thermocouple. I see you were able to do what took me almost 6 hours, in about 4 hours. My wood was mostly pine with some birch. Do you think that the wood type is the major difference between us? If you do not mind, could you let me know what your control settings and air settings are? If it is too much troouble I understand. Thanks again everyone.

 

[mr.fixit]

Hey no trouble.
I suppose the wood makes a difference in btu per pound but the oak I used was far from prime stuff and mostly smaller (under 4")Even so I doubt it would make a 2 hour difference.
My flue temp gauge is just a analog BBQ gauge threaded into the flue pipe about 2" but I've checked it with other temp gauges and it seems to be fairly accurate.
As for settings I run the fan shutter wide open. I do adjust the fan speed via the controller, normally at 90-100% at first start up and then down to 60 or 70%.
Primary air sliders are at 1/2" wide and secondarys are 3 1/2 turns out.
I normally have smoke free burns other than some at startup.
What model do you have? Is it the newer super with the cleaning handle and turbulators? Not sure if the older ones have turbulators, and without them stack temps will probably run higher.
Have your HX tubes ever been cleaned?Does it burn smoke free?
I Gotta go unload some more wood--WINTER IS JUST AROUND THE CORNER!

 

[stee6043]

It takes me the better part of two afternoons to get my 1,000 gallons up to temp each fall. It sounds to me like you're doing great...

 

[weiland13]

Fixit,
I have the newer style. Other than my secondaries, I run nearly the same.

Thank you everyone for the replies. It helps more than you know.

 

[jebatty]

It looks like my actual BTU/Hour output is only around 53000-55000. This is the part that concerns me the most. Am I figuring wrong?

btuH output to storage = 500 x 70 x 8.34 / 6 = 48650 (+ DHW draw). Your output calculation likely is close. An EKO 40 is rated at 137,000 btuH. I generally estimate average output over a wood load burn of around 75% of rated, or about 103,000 btuH. This estimate is derived from my experience in charging my 1000 gallon pressurized tank, no draws on the system at all during charging. Unless you are losing or using more output than you described, then I think you should expect more from the EKO 40, that is, close to 100,000 btuH output.

 

[weiland13]

I messed around again tonight. I was able to tweak more out of it. My flue temp is 450-475 when it is burning hot. I think the reason I have such a high temp is because the probe is only 1" from the back of the unit and does go into the center of the tube. My secondary chamber is not producing a huge ball of orange. It is a good hot blue flame.

 

[Hunderliggur]

First burn also has to dry out the refactory which absorbed moisture over the summer. Yes, wood does make a difference; pine burns hot but lower BTU/cu ft. I burned Saturday to make some hot water but didn't really time it.