Routine Maintenance on EKO 60?

[rickh1001]

I think I might be having some problems with my EKO 60 after about 1 1/2 months of more or less continuous use. I have an EKO 60 with 500 gal of pressurized storage. I am burning well seasoned and dry wood that has been stored in the basement alongside the EKO since mid summer, showing 12-19% on the moisture meter. I have been burning from the same 5 cords of wood, so no changes there.

It seems that for the last few days, I can't get the tank up to temperature, even if I burn a monster fire for hours. Previously, the tank would heat up fairly quickly, and with a full blown hot fire, I could get the entire tank up to 180 F without too much trouble. Now, despite a full hard burn, with good gasification, it seems I can barely get the boiler temp up to 170, much less the tank. The best way to describe it is that the boiler seems "lazy". It is almost as though the heat exchanger isn't exchanging as efficiently as it used to. I don't have a stack thermometer, but the connecting single wall stovepipe does seem hotter to the touch than it used to, although it is still not excessively hot.

I have the "Super" model, with the chrome arm on the left. The manual calls for moving the arm vigorously back and forth to clean the HX tubes. I do that regularly, and have added potatoes on several occasions, which really works to make the cresote flaky and loose. I have not pulled the smoke pipe yet - but I did check it about a month ago, and it had only a small amount of loose flaky stuff in it, so I doubt I have buildup in the chimney (24 ft of Metalbestos, running through the house).

Are there other parts of the boiler and heat exchangers that I should clean and check? As opposed to the older EKO, the manual says only to use the chrome arm, and doesn't say anything about taking the boiler apart to clean it. Should I clean the secondary air tubes?

Any ideas on why it doesn't seem to be heating the water as quickly or efficiently as it used to?

 

[Eric Johnson]

That's interesting. It's been colder, so my guess is that more of the the heat is going to heat your house. Getting a good stack temp reading would be a good idea. That's about the only place the heat could be going, though I doubt your heat exchanger is sooted up after such a short period of use. You can buy a barbeque thermometer that's in about the right temp range pretty cheap and insert it into a hole you drill in your stovepipe. That will tell you what your stack temps are. Should be in the 300-500 range under normal operation, I think.

Are both your fans working? Have you messed around with the controller settings?

Have you cleaned out the ashes really good? You need to get back under the turbulators (move the hx cleaning handle until your hoe tool will fit under them on one side, and drag the ashes out. Then move the handle again so that you can get under them on the other side.

 

[rickh1001]

Eric,

Thanks for the input. I haven't played too much with the various settings, and put them all back to the factory config. I had played with the fan speed a little, but now have the fans at 100%, with both blowers working, and the pie-shaped thing set at 50% on both (although I have experimented with it from 25-100%). When the fire is going, it roars, and there is intense gasification when I open the lower door, so all of that is working very well.

Your suggestion on getting the ashes out from the very back of the lower changer is an excellent one. I have to admit, I got lazy the last few times cleaning it, and only just raked out the ashes from the sides, without reaching way back into the rear HX area. Also, I never thought to lift the "turbulators" up to get underneath them with the hoe. Let me check that out tonight. It makes sense though, that there may be some significant ash buildup way in the back. Something has definitely changed, and that is the most obvious source of the problem. We have actually had some pretty warm weather lately, which is all the more reason that I noticed it not heating the tank as well as it used to. I'll let you know what I find when I go home tonight after work.

 

[Eric Johnson]

My pie-shaped air openings are set at about 1 inch, which I still think might be too far open. Nofossil has his set at just over one inch, as I recall, and said he noticed a difference in burn length when he went to that setting from a wider one. So I'd fool around with that, too.

The puzzling thing is that if you have good gasification, you're getting all kinds of heat, and it has to go somewhere. If the bottom of the hx tubes are clogged up with ashes, the heat can't really escape, so I'm not sure that's the problem

 

[Nofossil]

I think Eric is asking the right questions here. If you have a good and vigorous burn, the heat has to go somewhere.

It's good to get a set of baseline readings: inlet temp, outlet temp, and stack temp are all helpful. Heating storage as the only load is a great way to get an accurate measure of the output. Do you have a way to do that, perhaps by turning all the house thermostats down for a couple of hours?

That thing generates a lot of heat. I seriously doubt you could lose any sizable percentage up the flue without melting the flue. If the secondary combustion looks and sounds good, and there's no visible smoke, then you're getting the heat. It's just a matter of figuring out where it's going.

 

[rickh1001]

Nofossil,

Thanks. You and Eric are both right, and it is a little perplexing to me. I cleaned out the fine ashes lodged way back into the HX area - there was a significant pile I pulled out when I got done. We have been having some unusually warm weather over the past week, up into the 30's during the day, so there has been very little draw from the three zones I run. After cleaning, it seems to be doing better, but I would say it isn't back to its monster heat output status. I bought one of those magnetic stick on chimney thermometers at TSC on the way home from work (probably highly inaccurate). If one believes the reading, the black stovepipe is barely at 250F, even with a significant fire going on.

I have had an idea in the back of my head for a while, that the low atmospheric pressure and higher temps are reducing the chimney draw enough that it is just making for a very lazy fire, despite the excellent gasification going on. I don't have any easy way to measure the chimney draft. I wonder if I just need some cold, clear air to increase the chimney draw. Speaking of which, while on this topic, with the sealed combustion chambers and the fans, does the Eko act almost as a forced draft furnace, or is the chimney draft still important?

All I know is that I can fill the upper chamber 3/4 or so with excellent, very dry hardwood, have a roaring gasification, and I can barely get 170 F on the controller reading, or on the analog temp/pressure gauge on the supply side of the boiler, right after the air separator - even tonight with 25-30F weather. So it is not just a question of an inaccurate controller reading. The storage tank in the basement is uninsulated, but it has been since I installed it, and the cellar temp is usually about 80F, which keeps the upstairs rooms at 70F from the floor temperature. In cold weather, I used to have the tank up to 180+F with no problem. So unless something is wrong, I am now leaning towards the poor draft chimney idea with the warmer weather.

 

[Eric Johnson]

You do need draft, though I doubt you'd get very good gasification if your draft was poor. You have to compensate for surface-mount stovepipe thermometers, since the surface of the pipe reads lower than the inside stack temp. They're designed to monitor the fire danger to flammables. But I think if you can find out the conversion factor, you can get close.

 

[bois3]

I had a similar experiance this past weekend, altough i do not have any storage yet, I noticed that my eko 40 could not keep up to the load as well as it had in the past. After cleaning the ash from the lower chamber I check the insulated chimney and found that the fly ash had accumulated in the clean out to the point that the passage was 50% blocked as well the ash had bilt up in the black pipe. Cleaned it and now back to 100%

 

[markpee]

I had a similar experiance this past weekend, altough i do not have any storage yet, I noticed that my eko 40 could not keep up to the load as well as it had in the past. After cleaning the ash from the lower chamber I check the insulated chimney and found that the fly ash had accumulated in the clean out to the point that the passage was 50% blocked as well the ash had bilt up in the black pipe. Cleaned it and now back to 100%

I'm experiencing something similar as well. I can't get "great" gasification and my temp hovers in the 150 range - I do have a lot of fly ash in the base of my chimney. I'll have to try to get it out later - I'm probably close to 50% blocked as well. Overall my 40 seems "sluggish".

 

[Eric Johnson]

This is interesting. I've never had a problem with my boiler producing too little heat. My problems are more in the idle category, which is to say that my house zones get satisfied, and then I have to decide whether to keep the fire going, or let it go out. This is a tough decision at, say, 10:00 p.m.

One observation I do have on the EKO (and probably other gasifiers with a similar design) is that it takes awhile for it to get up to temp. But once it does, maintaining it is not a problem. So I'm surprised to hear that people are having problems reaching/maintaining a decent water temperature. That's usually the sign of an undersized boiler for conditions, which simply CAN'T be the case with an EKO 60, IMO.

 

[Tony H]

I had a similar experiance this past weekend, altough i do not have any storage yet, I noticed that my eko 40 could not keep up to the load as well as it had in the past. After cleaning the ash from the lower chamber I check the insulated chimney and found that the fly ash had accumulated in the clean out to the point that the passage was 50% blocked as well the ash had bilt up in the black pipe. Cleaned it and now back to 100%

I'm experiencing something similar as well. I can't get "great" gasification and my temp hovers in the 150 range - I do have a lot of fly ash in the base of my chimney. I'll have to try to get it out later - I'm probably close to 50% blocked as well. Overall my 40 seems "sluggish".

I also had a large buildup of ash in the cleanout and blocking the opening partly. I have been cleaning the ash out every filling to see if that was the problem

 

[rickh1001]

Just as a follow up to this thread. I had initially complained of seeming low heat output from the EKO 60. This morning, I dismantaled everything on the EKO 60 to check for any obstructions, and to re-check all the settings. The smoke pipe and chimney were clean as a whistle, with only a small accumulation of granular, sand like ashes. The entire chimney is perfectly clean, with no cresote or buildup of any kind. The EKO has been running for close to 2 months now, with 3 cords of wood through it, so it shows how cleanly it is burning. I re-checked to primary air, and set them to 10 mm (they were at 9), in anticipation of starting into a new stack of wood with a little more moisture content. The air flappers behind the blower fans were free. I cleaned every bit of ash I could find in the back by the heat exchnagers. When the pipe was off, the whole heat exchanger area was very clean, with only a light buildup of dusty stuff.

I was also wondering if the heat exchangers might be plugged from the other side - that is, could any crud have accumulated at the bottom of the boiler and the water tubes. Short of cutting the boiler apart, all I could do was back-flush the boiler by shutting of the many valves I installed on it, and purging the water from the outlet out to the top purge valve. The water coming out was very clean, with no traces of sediment.

I am running it full blast today to bring the storage back up to temp, with no zones running, so I should have a good baseline as to the heat output. I won't be able to accurately compare it until tonight after I get my storage back up to temp.

One thing my son and I both noticed last night, as the temps started to drop towards 20F or so, the boiler picked up noticably. I was finally getting over 180F for the first time in a while. Since I can't find anything wrong with the boiler, and I haven't drastically changed any settings, I am wondering if I am a little short on chimney draft. In the warmer weather we've been having, I wonder if the draft is just marginal, but picking up when colder weather comes back? I have no way to measure it, but perhaps I can call up our (former) oil dealer to see if he can measure it when running. I am also wondering if some of the others who complained of the same symptoms, if they could all be due to the recent bout of warmer weather. If a chimney has marginal draft, it might work in the cold, but degrade enough in warmer weather to cause a perceptable drop in performance. I have sealed up all the joints with aluminum duct tape. I thought my chimney run was 24 ft, but I realize it is only 21 ft of 8" metalbestos. Perhaps I need to put a little more chimney on this thing to strengthen the draft? Would this make any sense?

 

[rickh1001]

Checked the Eko tonight, and it has been working like a champ. My storage is fully charged at 180+F, and the boiler is idling with 186F water, when I set the temp at 190F. So go figure. The only thing I can come up with is the colder weather is letting the chimney draw better, since I couldn't find a thing wrong when I cleaned the chimney and checked the boiler settings.