Lambda Type Owners - Highest Secondary Settings Seen?

[hiker88]

On your Froling do you have (1) fan, (1) Lambda sensor, (1) smoke temperature sensor and individual stepper/servo motors for both the primary and secondary drafts?

Thanks!

Yes, sorry missed this question.

 

[__dan]

Thanks for that. Although we have the same boiler it is hard for me and my limited experience to compare since our set up is pretty different. I've only made changes two settings. My slumber temp is 90c ( i think 85 or 87 was the default) and there was a timer setting that Tarm walked me though changing in the service menu. I was getting some erroneous "boiler has air leak" message related to the residual oxygen readings. I was burning some real gnarly pieces of wood at the beginning of the season and as a safety, the boiler was interpreting the high residual oxygen content settings as a leak, or leaving a door open. Once Tarm walked me through the change I never got the message again.

With 220 c flu gas temp I hit 64% on the secondary last night. Our TV room is in the basement, and when I really hear it rumbling I go out for a look. My wife thinks it's dorky as anything, but like I said, I'm a gadget guy and just generally curious about these kind of things.

Yep, I've been constantly going outside to look at the flue exhaust then downstairs to look at the boiler temps, like twice an hour. At 35% draft fan speed it's quieter than the circs. I have to look at the dial thermometers in the HW header then look at the LCD on the Froling to see if it is running. Standing right next to it, I cannot hear it over the circs at minimum burn. Cannot hear anything upstairs which is a big plus over the oil boiler.

Because of the low flue gas temp and sloppy wood from outside, I see the the H2O steam condensate in the flue gas. In the first hour from a cold start when it's dehydrating the wood I see ~ 10 ft streamer of H2O and ~ 2 ft streamer of H2O at minimum burn.

I've been looking for grey smoke and saw it for the first time today. I had brought in all wood pieces that had fallen off the pile and were close to the ground, outside of the tarp cover and loaded that, probably waterlogged, moldly, mushroomy. I am cleaning up and burning the junk. The first hour was slow to burn and in the flue gas I could see the steam going up and there was some unburned grey smoke that separated out of the steam and fell to the ground. I could smell it. First time in 7 weeks and due to low quality wood picked up from close to the ground. Pretty much what I expect to see from the neighbors burning.

All the other burns I've been watching the flue gas closely. It's water vapor and you can see it wisp and evaporate to the air in 2 to 10 ft with no residue. I'm sure you have the invisible flue gas because of the higher temp flue gas.

I'm waiting for January to see what it does with the red oak splits. I running well under what I had guessed I would burn. At this rate I will have a pile of junk wood left over for next year. Next improvement is wood storage.

 

[EffectaBoilerUser (USA)]

What I am saying is:

The Co content over time averaged 490 PPM with the Lambda sensor activated
The Co2 content over time averaged 13.2% with the Lambda sensor activated
The boiler efficiency over time was 92% with the Lambda sensor activated


The cumulative Co content over time averaged 2,721 PPM with the Lambda sensor NOT activated
The Co2 content over time averaged 10.2% with the Lambda sensor NOT activated
The boiler efficiency over time was 87% with the Lambda sensor NOT activated
As can be see from the above test data, the Co PPM is drastically reduced when the Lambda sensor is activated.

 

[EffectaBoilerUser (USA)]

Opps!

This is what I meant to post - don't want to confuse anyone!


The Co content over time averaged 490 PPM with the Lambda sensor activated
The Co2 content over time averaged 13.2% with the Lambda sensor activated
The boiler efficiency over time was 92% with the Lambda sensor activated


The Co content over time averaged 2,721 PPM with the Lambda sensor NOT activated
The Co2 content over time averaged 10.2% with the Lambda sensor NOT activated
The boiler efficiency over time was 87% with the Lambda sensor NOT activated


As can be seen from the above test data, the Co PPM is drastically reduced when the Lambda sensor is activated.

 

[stee6043]

Where do your boiler efficiency numbers come from? How were the calculated? Just curious.

 

[BoilerBob]

Effecta used to be on my favs list. Now I am sick of hearing that name.

Paul

 

[Tennman]

Enjoying this thread.... A non-lambda guy learning a lot. Thx

 

[EffectaBoilerUser (USA)]

The efficiency #'s are generated/calculated using the European Test Method EN303-5. I do not know the exact details of this efficiency test setup/method but do know that it looks at how much did the water temperature of a given volume increased when a specified amount of fuel was burned in the boiler.

I will look into this efficiency test method further and get some additional details to share with everyone.

Regarding the other data figures I presented, they were gathered using calibrated/ISO certified instrumentation and I have attached the performance graph of this actual test.

 

[JP11]

Enjoying this thread.... A non-lambda guy learning a lot. Thx

I've got one. I'm into a lot of this stuff.. in waves.

For now... I'm content with the oil boiler not coming on. I need to keep cutting wood and getting ahead. Drier wood is more important that about anything else.

Hit the button, load, hit the button. Keep the storage temps up.. don't over feed the boiler so it doesn't idle.

JP

 

[EffectaBoilerUser (USA)]

Not quite sure why the performance graph did not post, lets try this again!

 

[EffectaBoilerUser (USA)]

Lets try this one more time!

I agree that the most important (and simplest to control) item with any wood gasifier is the moisture content of the wood being burned.

 

[EffectaBoilerUser (USA)]

Now its really go me puzzled.

I am attaching the performance graph but it is not showing up on the posting.

Lets try it one more time.

 

[EffectaBoilerUser (USA)]

Regarding the question about the efficiency test method, I have attached a sheet that shows all of the different test methods used to Test/Certify the effecta Lambda boilers.

 

[mikefrommaine]

So you used those standards when you came up with your efficency numbers? 92% wouldnt the boiler be condensing at that point?

 

[TCaldwell]

Hiker & Dan, I am curious, at startup what are the p/s damper positions and fan speed. What conditions or events cause the fan speed to modulate and did you say the normal operating residual o2 runs between 10 and 16%.
thanks
tom

 

[__dan]

Hiker & Dan, I am curious, at startup what are the p/s damper positions and fan speed. What conditions or events cause the fan speed to modulate and did you say the normal operating residual o2 runs between 10 and 16%.
thanks
tom

Startup is max load for me since the boiler, DHW, and heat have been off for at least 12 hours. Boiler may be 36 C and the circs launch at 67 C (15 minutes after lighting).

At startup, I have the draft fan max speed set for 75%, down from the factory default at 80%, primary air is either 90 or 100%, and the secondary air seems to be set by the lamda sensor feedback. Secondary air usually runs at the minimum opening of 10%. The Froling excess O2 setpoint is 8% but it will not close the secondary air below the minimum opening of 10%, so for my typical burn when the boiler is turning down and restricting output, excess O2 is typically 12%. The Froling detects fuel load burnout at, I believe, 19% excess O2. and goes off.

So typically for me, I have max load for 1 hour, draft fan 75%, primary air 100%, secondary air 10%. After 1 hour the DHW load drops out and the boiler is at or above the HWS setpoint of 73 C and starts to turn down the output. With the loss of the DHW load and the slab returning 100 deg F, going from max to min operating condition is ~ 10 minutes. The Froling goes right from max to min parameters because HWS temp is above the setpoint of 73 C. 35% draft fan, 20% primary air, 10% secondary air. The boiler is at the minimum operating setpoints.

With moderately dry wood the basement slab is not enough load for the mimimum burn rate and the HWS temp continues up typically to the 80 to 90 C range and 12% excess O2 (above HWS and excess O2 setpoints). Flue gas runs 110 C at min burn rate. It burns out with no slumbering ~ 3 hours later because of the half load of fuel.

If I open the boiler later in the burn when it's charcoalized and poke it, it will go to 20% primary air and 50% secondary air, draft fan speed stays at 35% after I close the door. (HWS temp above setpoint)

 

[EffectaBoilerUser (USA)]

I will investigate efficiency ratings in greater detail with Effecta. I am not sure exactly how the displayed efficiency is calculated.

On my Effecta at start up the primary defaults to 70% open and the secondary to 30% open. Once a fire is made and the smoke temp. reaches 100C the dampers then go to 100% primary and 0% secondary in an effort to get the combustion process going as quick as possible! At this temp the Lambda control system is also activated as the burn continues the Lambda system will automatically change the primary and secondary dampers to maintain the target CO2 setting.

 

[stee6043]

So you used those standards when you came up with your efficency numbers? 92% wouldnt the boiler be condensing at that point?

That's exactly why I was asking the question. Boiler efficiencies that exceed 90% are generally going to be condensing. That being said, we could debate boiler efficiency, combustion efficiency, system efficiency, etc and so on. They all have different meanings. At the end of the day none of us could ever truly compare our boilers to any others in an installed configuration because of the variables.

My EKO advertises "91%-95% overall system efficiency when properly installed and operated". I'd like to think I have a pretty good thing going with it but I can tell you that on average I'm not doing better than low 80%'s. I also know that my brother-in-law is seeing high 20%'s, low 30%'s with his Central Boiler OWB. Ultimately, based on what I know about my system I could say with high confidence that a lambda boiler (Froiling or otherwise) would not substantially improve my system efficiency. I might not have to adjust my air settings two or three times each burn but I'm quite certain the efficiency numbers are going to be right in line with the EKO.

 

[EffectaBoilerUser (USA)]

If you look at the performance graph I posted yesterday morning you will see that the efficiency % with and without the Lambda sensor was a difference of 6%. Thus, yes, the efficiency is not greatly increased with the use of a Lambda control system.

The biggest difference is that of the 4x reduction of CO PPM.

Having owned and operated an EKO40 for two years before I installed the Effecta Lambda 35, I do like the fit that there is no by-pass lever on the Effecta boiler to mess with. Once the fire is lit the primary door is closed and the Lambda system controls the damper opening automatically. It is also nice to be able to adjust my target CO2% (for different wood types and moisture content) with the touch of a button and know that the lambda system will automatically adjust the dampers for the most efficient burn.

Gotta go to Church!

 

[skfire]

Thanks for that. Although we have the same boiler it is hard for me and my limited experience to compare since our set up is pretty different. I've only made changes two settings. My slumber temp is 90c ( i think 85 or 87 was the default) and there was a timer setting that Tarm walked me though changing in the service menu. I was getting some erroneous "boiler has air leak" message related to the residual oxygen readings. I was burning some real gnarly pieces of wood at the beginning of the season and as a safety, the boiler was interpreting the high residual oxygen content settings as a leak, or leaving a door open. Once Tarm walked me through the change I never got the message again.

With 220 c flu gas temp I hit 64% on the secondary last night. Our TV room is in the basement, and when I really hear it rumbling I go out for a look. My wife thinks it's dorky as anything, but like I said, I'm a gadget guy and just generally curious about these kind of things.

I think the factory setpoints for FG is 160 and for boiler temp is 80(I have to chk). I have bumped mine to 87.

Have you tried brushing the HX? 220c maybe a bit high, if you a getting it a lot.

The wife has been running the boiler for the last month(had an accident) and she is loving it, but seeing FG over 205, I tend to get ready for a brushing. Last night mid burn(oak,ash and cherry. 65%full box) it reached FG 207c, Boiler 86c, primary closed to 75%, secondary at 39% and fan speed at 79%.

I try to clean the HX every 150 hrs or so and have only fine powder like fly ash.

Scott

 

[skfire]

Hiker & Dan, I am curious, at startup what are the p/s damper positions and fan speed. What conditions or events cause the fan speed to modulate and did you say the normal operating residual o2 runs between 10 and 16%.
thanks
tom

At start up(first 10 minutes or so), primary runs at 99%, secondary at 10% and fan at 85%

As the setpoint of 8% O2 level is reached and past, around 6.5% the sec starts modulating up.

Scott

 

[NP ALASKA]

Guys please let me know if the Lambda stuff starts somewhere else this is great info
What a hobby my wife says. I wish i liked going to work this much
Lol

 

[hiker88]

Well, it looks like my morning burn on 12/09 has answered my question. I don't think I'll be seeing secondary settings any higher than this.

I think this was about 45-60 mins into the burn. Previous fire was 24 hours before. Got up Sunday with the house at 66 and storage in the high 50s celsius. If I had had the system in "auto backup" the oil furnace would have come on. Goal was to get the house up to 70 and charge storage for the next 24 hour cycle.

With the temps lately, and two zones calling for heat, the Froling will run at it's highest setting with the safety door closed (85% fan speed) - and stay about 84-86c. My boiler setpoint is 90c. The first floor always comes up to temp first. Once the first floor zone stops calling for heat, the temp of the boiler will come up a few more degrees, but the boiler will still usually run at 85%.

With no zones calling for heat, storage starts coming up quickly, and the boiler will reach it's setpoint and maybe get as high as 92c. The fan is modulating down at this point. Boiler temps usually stay at 90c with fan speeds as low as 35%. As the wood starts to burn out, the fan will gradually increase as it tries to keep boiler temp up.

The holes you see to the right of the lighting door (on the black metal outside of the primary chamber) are the air inlets for the primary chamber. There is a tunnel in the insulation that leads along the side of the boiler. Air is pulled in through these holes and runs along the side of the boiler plating where it is preheated, it then gets pulled in through a butterfly vale and into the primary chamber. The air inlets for the secondary are similar except that that air is actually injected in the nozzle area, not the secondary chamber proper. To avoid confusion, the holes you see in the primary chamber are not air inlets - those holes are in the cladding plates that line the primary. The cladding plates come out for cleaning.

 

[Chris Hoskin]

for anyone interested in the gory details of the difference between the European method of calculating efficiency and the North American, you may find our blog post from June 2009 interesting. The difference has to do with how moisture is treated: the Europeans use the Lower Heating Value of the fuel and we use the Higher Heating Value. The result is that a European tested efficiency of, say, 92% translates to a North American efficiency of something like 86%. That is how a boiler that touts an efficiency of 92% can still be non-condensing. Gory details: http://blog.woodboilers.com/2009/06/european-union-to-north-american-wood.html This is just one of the places that there is confusion in the marketplace and why we tend to talk about our boilers as being "over 80% efficient" instead of citing specific numbers that are derived in a lab. At the end of the day, all the bells and whistles make a boiler easier to use, more efficient and cleaner burning to be sure, but the most important accessory that people can add is a decent wood shed.