EKO Controller Insight?

[Eric Johnson]

It only seems to happen when it's really cold, but occasionally my controller will go into "FUEL" mode when there's still plenty of wood in the firebox--generally in the middle of the night. It's disheartening to wake up to a cold house and a boiler full of fuel.

In looking over and trying to decipher the manual, I think I can fix this problem by extending the "working" fuel-detection parameter from the factory setting of 2 hours to either 3 hours or the max, which is 4 hours. But since I don't really understand what's happening, I'm hoping someone with a clearer understanding can provide some insight and guidance.

Because I don't have storage, the boiler tends to idle more during cold weather, probably because we're keeping it fired up good. It's not uncommon for me to visit the boiler just before going to bed, to find the temp at 190 and the firebox more or less empty and the house is warm. So, whaddydo? Well hell, I fill it up and go to bed. This is typically when this problem occurs.

I realize the storage would solve this problem, but I'm looking for a quicker, easier and cheaper fix for the time being. The older model controller, which I've used for most of the past 8 years, didn't have this problem, probably because it's a lot less flexible. And, it never blew capacitors, unlike the two more modern "spares" that I have on hand. I'd switch back, but I'm looking forward to playing around with the new, capacitor-repaired units. Seems like some opportunities for greater efficiency, such as modulating the blowers down in cold weather.

 

[stee6043]

Usually I get the FUEL warning when the fire peters out during an extended idle period at the end of a burn. You can adjust how long the unit keeps testing for fire but this won't help if the fire did indeed go out. Do you think jamming the firebox full of cold (maybe damp?) wood during idle may be killing your fire? That would be my first guess. Your coal bed isn't able to keep the fire going with just the small amount of air it gets during idle.

 

[Hydronics]

Eric,
Increase the fan purge run time from 5 to 7 sec, decrease the time between purges a bit. I forget the default. This will keep the coal bed hotter and ready to ignite the wood on demand.
Also increase the Working time before FUEL shutdown, I think default is 1 hr, set it at 2.
As Stee Suggested, a load of cold damp wood is probably preventing gasification from starting once the demand called.
The changes fixed the issue for me.
I could tell you the specific parameters if you're unable to figure them out. The polish to English translation of the manual leaves a bit to be desired.

 

[Medman]

I agree with the above, and I would add that every time you load the boiler you press STOP and then START again. This resets the timer for the FUEL indicator. I have had issues where I loaded fresh wood on an existing coal bed and didn't reset the timer. The boiler took too long to reach the set temp the next time it cycled and went to FUEL even though there was a full load of wood. This is due to having two timers - 1 that sets the time it takes to get up to temp from cold, and another that sets the time it takes to go from set point to set point again. I can't recall offhand what the parameters are for each; I can look it up.

 

[BoiledOver]

In looking over and trying to decipher the manual, I think I can fix this problem by extending the "working" fuel-detection parameter from the factory setting of 2 hours to either 3 hours or the max, which is 4 hours. But since I don't really understand what's happening, I'm hoping someone with a clearer understanding can provide some insight and guidance.

I believe the working fuel detection acts like this: When starting a fire the timer for detection begins, if the boiler setpoint (temperature) is not reached within the timers setpoint (hours/minutes), the boiler shutdown process takes place and the FUEL is indicated. Also, after the boiler setpoint is reached during a burn, the timer is reset and if the boiler fails to reach boiler setpoint again, the shutdown process takes place. <----- Like when the fuel is all burned.

It seems that boiler setpoint and timer setpoint would be adjusted to solve this issue. In addition, dialing back your house thermostat for the night could also contribute to this issue.

 

[stee6043]

Eric,
Increase the fan purge run time from 5 to 7 sec, decrease the time between purges a bit. I forget the default. This will keep the coal bed hotter and ready to ignite the wood on demand.
Also increase the Working time before FUEL shutdown, I think default is 1 hr, set it at 2.
As Stee Suggested, a load of cold damp wood is probably preventing gasification from starting once the demand called.
The changes fixed the issue for me.
I could tell you the specific parameters if you're unable to figure them out. The polish to English translation of the manual leaves a bit to be desired.

It's funny, I was going to suggest this same thing but I couldn't find the commands for the purge in the new manual. I'm not sure you can set the purge in the newer controllers? I was certain I could set it in mine though...

 

[Eric Johnson]

Thanks, everyone. Just the information I was looking for.

 

[Medman]

You can set the purge in the newer controller - I increased mine to 7 sec and 6 minutes between - Default is 5 sec and 10 min.

 

[timberr]

Eric

BoiledOver is correct on what is going on. Since it is really cold out your boiler isn't getting the chance to get ahead and reach the Desired Working Temp (set by knob). The logic in the control is if after the X Hrs the boiler hasn't reached the Max Temp setting then there isn't any fuel. Try lowering the Working Temp (Turn down the knob) Setting since increasing the time on the Fb30 (No Fuel Testing During Work) will likely result in the same problem.

What are you seeing for Boiler Temp in relation to your working temp setting?

 

[Eric Johnson]

Nice avatar, timberr. Ever heard of Northern Logger magazine?

Currently I have it set for 190 and it lands at about 195. I could certainly turn it down and see if that works better.

My wood is pretty dry, but it is cold, since it's stacked in an unheated area of my barn.

 

[timberr]

I am happy subscriber to Northern Logger, In fact in the October 2014 issue they did a story on a timber sale I was conducting (I am the forester). Some really nice white pine at the Blackwater Reservoir.

Man if you are hitting the working temp it shouldn't happen. Guess you will have to stay up all night long with a stop watch to see what is going on. I did have that problem when I first started my boiler in 2008. I had to set the Fb30 to 4 hrs. but my wood was on the wet side. Now I have it set to 1 hr. and things work fine.

 

[stee6043]

Eric

BoiledOver is correct on what is going on. Since it is really cold out your boiler isn't getting the chance to get ahead and reach the Desired Working Temp (set by knob). The logic in the control is if after the X Hrs the boiler hasn't reached the Max Temp setting then there isn't any fuel. Try lowering the Working Temp (Turn down the knob) Setting since increasing the time on the Fb30 (No Fuel Testing During Work) will likely result in the same problem.

What are you seeing for Boiler Temp in relation to your working temp setting?

I know this is the way the manual reads but this is not the way the controller actually works. I believe when the manual says "thermostat" it actually means the external thermostat which most of us do not run.

The controller wants to see a certain amount of temperature increase after it enters work mode to know it's actually firing. It's not looking for the max temp set by the knob. I have my controller set at max temp 100% of the time and it only achieves max temp in the last couple hours of most burns. The boiler will run fine with the temp knob maxed out but output temps chug along at only 170-180.

 

[Eric Johnson]

I'm the editor. That was a good story (by the other Eric Johnson) about Ryan Mingerilli in October. Not too many young guys start from scratch in this industry anymore.

I'd be willing to bet that on the occasions when it reverts to FUEL mode with a full firebox that my boiler is not able to hit the set temp. So, I'll turn it down, especially on cold nights, and see how that works.

Thanks!

 

[TCaldwell]

Id bet your wood is well seasoned, think I remember seeing a picture of rows that you said totaled 40 cord

 

[Eric Johnson]

TC--I'm down to a 15-cord reserve. So, at the beginning of the heating season, I shoot for 10 dry cords stacked in the barn and another 15 cords drying out back for the following season.

Back when I had 42 cords of mostly beech but and stacked, I got a bit ahead of the game and lost a fair amount to rot. But, I was laid up for one summer, so at least we had enough in reserve to get us through one winter with no problem, rot notwithstanding.

 

[Fred61]

I agree with the above, and I would add that every time you load the boiler you press STOP and then START again

I never shut down the fan to check the burn or to reload. The only time the combustion fan shuts off is when it goes into idle or at the end of my burn.

 

[woodsmaster]

I never shut down the fan to check the burn or to reload. The only time the combustion fan shuts off is when it goes into idle or at the end of my burn.

He's not saying to shut it off to reload. Just hit stop and then start immediately after to reset the timer.

 

[ihookem]

Eric, I don't have storage neither and this is how I run my EKO 25. I load it up on top of hot coals. I press stop cause that resets the timer. Was a time I had the same problem. I also set the controller to 4 hrs. so it has plenty of time to get to temp. One thing seems strange is how high you keep your temp (190) I set it at about 165 when it is about 15 degrees or warmer. When it gets real cold like the last few nights I set it to 175 in the day and 165 at night. This keeps my house at about 66-68 degrees . I only use my 1,000ft of 1/2" pex under the floor ( staple up) . This works well down to 0 degrees with no wind. Colder than that I have to run the HX in the furnace. Problem is, the HX lowers the boilers water temp very fast. I raise the furnaces thermostat 1 degree ore so and we are fine. You will save a lot of wood if you turn down to about 165. It should work real well that way with your big boiler. I can't imagine you having that big of a heat load that you need to keep water temps at 195.

 

[Eric Johnson]

You will save a lot of wood if you turn down to about 165. It should work real well that way with your big boiler. I can't imagine you having that big of a heat load that you need to keep water temps at 195.

Thanks for that tip. I guess I always assumed that hotter is better, but I've been throttling it back and it seems to be consuming less wood. So I appreciate the help. I think that without storage, there's always the temptation to bump up the temp when the thing is idling to get it into more productive gasification mode. Over time, you wind up at the max.