E-Classic 2400 Issue Revisitied

[Cass007]

So last week I posted my graphs and was asking about the furnace not seeming to want to heat above 750*F. I got one response from garret that reassured me that there may not be an issue and that several factor could be at play. I later reached my dealer and he said as long as the water is heating and staying within the temp parameters set for it, he doesn't see an issue.

I explained that the furnace used to kick right into high mode and heat quickly and now seems to stay in medium mode and burn longer. He said the furnace has "learned that it doesn't need to go into high mode to heat your house (3500sq ft + 4 car garage)". I was told the furnace has a memory and adjusts its burn to the past cycles it has seen at similar outside temps and heat demand loads. Is there any truth to this at all?

This logic seemed flawed to me, I would think the furnace would heat as quickly as possible and then turn off to be more efficient, but I really don't know. It's my first season with the furnace, so I'm learning as I go. Regardless .... I just ran out of wood yesterday, so I shut it down and had a chance today to do a thorough clean out.

This is what I found ...

Burn Box air passages ... Fine, except the lower rear hole, it is clogged with creosote. I took the side panels off and was happy to see how clean they were. The fronts were a bit clogged as well, but only some ash there.

Stack ... stack looks good and clean. There was a buildup of ash at the elbow where it goes vertical, but no biggie. Now the chamber that connects the stack to the heat exchangers .... wow. That had ash buildup 5-6" deep. I think that is a design issue though, since the stack is up that same height above that chamber. There was good airflow.

Heat exchangers ... just fine. Little ash covered, but all good there. Same big ash deposit right at the top near the rear clean out cover, but again, it's a design issue.

Water level and PH ... on point.

Then things got interesting .... I decided to pull the elbows since if heard people talk about possible buildup there ... OMG!!!

Secondary elbow ... a bit sooty, but just fine.

Primary elbow ... NIGHTMARE, the elbow and tube were 80% blocked off (see pics). I have no idea what the issue is, but I'm sure this is my problem.

The question I have is ... When you open the bypass and then open the airbox where the blower in the rear of the furnace, should all 3 solenoids be open? I see the 2/3 solenoids are open, but the primary is always shut on mine. I fear I may have a bad solenoid and that is why the buildup happened and then the blockage began choking the fire so it couldn't stay in high mode. Or I'm way off base and there is nothing wrong.

Any advice from those with some knowledge is appreciated. I love this furnace, the world is an imperfect place and parts fail. The money I saved not having to burn LP this season was tremendous. I just want to do what I can to make sure it has a long lifespan and shorten my personal learning curve at the same time.

Pics in post below.

[Cass007]

Had to load as singles for some reason ... pics of the Primary Air Tube just behind the elbow.

First pic is the elbow ... last 4 are the tube. Big chunks of creosote and buildup came out. Only good part is that it came out fairly easily.



 

 

 

[beenthere]

They look to be the same picture, but for one.  Or am  I missing something? 

[Cass007]

They are similar ... I tried getting better views with and without the flash, but I was filthy and then dropped my phone in the snow. I had a hard time loading the pics, so I just posted them all.

[beenthere]

Might want to read the rules about posting "all" pics.  

Looks like your wood may have been too wet to get good burning, or trying to burn too much for too long a burn, thus the 2400 went through long periods of times when it was shut down ( making creosote).

But now you know, and can work on adjusting more to the details. 

[AsaG]

Your dealer is pullin' ur leg about the control "learning" anything.  Aside from some rudimentary RS-485 communications in the Firestar II, it's not that sophisticated.  Things happen at defined set-points and/or times and that's that.

My stage 1 (primary) is closed and, depending on the reaction chamber temps, either the second stage or both second and third are open when the bypass and door are open.  Yours sounds like it's doing what it's supposed to.

The elbows, especially the primary, clog with creosote.  Very dry wood extends cleaning cycle but they clog and need to be checked monthly.  I leave a stubby 5/16" and 1/4" nut driver as well as a scraper in the plumbing/air-box area just for the purpose.  Not sure about later model 2400's but on my 3200 the rear door is hinged and fully insulated.  This keeps the goodies in the back of the boiler warm and toasty during shutdown.  This CB design has helped with the clogging in the elbows.  They still get some buildup but not as bad as the 2400 I had previously.  A buddy took some 3/4" foil faced foam sheathing and insulated the back panels on his 2400.  He also insulated a good portion of the rear mechanical area with foil faced bubble wrap taking care to allow for intake air.  He claims it's really helped with clogging and condensation in the air box.   

Even if your heat exchanger tubes look clean, they probably aren't and could use some attention.  Even a light coating of dust makes quite a difference in air-flow and over-all performance.  I don't use my XP all of the time but, once you have a known baseline of operation, the data it provides can be invaluable for troubleshooting.

Also, make sure the nut and bolt that connects the damper plate(s) to the solenoid(s) aren't loose or corroded.  Some of the originals were not SS and would rot away.  The solenoid would actuate but the damper plate would either not open all the way or not open at all. 

[sam-tip]

This is normal.  I had to replaced my primary tube after the first year.  It rusted apart.  Drier wood does help.  Plus do you have the spring on the primary cover to hold the cover down.  Burning until you get fire out warning more often will help dry the boiler out too. 

Central boiler has send me notices about cleaning the elbow and burning/drying down the boiler.

[Roger2561]

This is normal.  I had to replaced my primary tube after the first year.  It rusted apart.  Drier wood does help.  Plus do you have the spring on the primary cover to hold the cover down.  Burning until you get fire out warning more often will help dry the boiler out too. 

Central boiler has send me notices about cleaning the elbow and burning/drying down the boiler.

sam-tip; On my E-Classic 1400 I'll have to replace the primary air elbow.  When I took it out to clean it last week, I noticed that it was getting rather thin on the part that goes into the rubber piece that holds it place.  I'll be checking with the machinists in our building to see if they can make one out stainless steel instead of buying a new one made of steel.  Roger

[garret]

Sorry, forgot to mention the primary air elbow issue.  Didn't think you were operating long enough to have a problem with this yet, as it is usually once a season for most.  I am burning exceptionally dry wood, yet had to clean mine once, probably due to much idle time during September and early October when there is low demand.  Its an easy fix; about 10 minutes with a screwdriver and a shop vac.

All three solenoids should operate.  There is a mode on the Firestar II controller that will open and close all three for test purposes, consult the manual.

As for the burn cycle memory thing, that's news to me.  I haven't observed such behavior.

Good Luck and enjoy your 2400.  I like mine a lot, but starting to grow less fond as spring approaches.  Will probably start liking it again come August.

[don leclair]

When cleaning the elbow and using the shop vac., be real careful about the filter inside the vac catching fire.  Very easy to suck out some hot creo. and two hours later you have a problem.  Leave the vac outside or take the filter out and leave that outside. Just a word of caution from experience.

[garret]

 Remove the filter and pour in some water (if it is a wet/dry design).

[Bob Lentz]

I pull my EC 2400 elbows 3 times a year.  I use a torch to heat the creosote and then scrape it out of the elbow using the wonder bar that came with the boiler. On the boiler side, i use the torch to heat and scrape the muck out of the tubes as well.  This is just part of the maintenance if have learned to do.  When i first bought the boiler, I had no idea what the maintenance load would be.  I sure found out! (the hard way). 

I also use the torch to heat up the air chambers through the air holes to burn creosote out.  It just melts and runs into the firebox.  If you just resign yourself to the maintenance, you can keep your unit working great. 

don't forget to lube your blower motor!  CB says nothing about this, but i brought one back from the dead by just lubing it.

[Bob Lentz]

I pull my EC 2400 elbows 3 times a year.  I use a torch to heat the creosote and then scrape it out of the elbow using the wonder bar that came with the boiler. On the boiler side, i use the torch to heat and scrape the muck out of the tubes as well.  This is just part of the maintenance if have learned to do.  When i first bought the boiler, I had no idea what the maintenance load would be.  I sure found out! (the hard way). 

I also use the torch to heat up the air chambers through the air holes to burn creosote out.  It just melts and runs into the firebox.  If you just resign yourself to the maintenance, you can keep your unit working great. 

don't forget to lube your blower motor!  CB says nothing about this, but i brought one back from the dead by just lubing it.

[Roger2561]

Bob Lentz - I have the E-Classic 1400 but like you I too clear the elbow and tube of creosote build every month only I use a large screwdriver for both.  What kind of torch do you use?  Something like a plumber would use to sweat copper fittings or something more like oxy/aceteline?  Thanks, Roger 

[Bob Lentz]

i use a basic propane torch. you can get them at Home Depot or Lowes or any hardware store.
I was thinking about getting a heating wand that connects to a 20lb propane tank. They use them to heat asphalt for roof repairs-installation and to melt ice.  It would burn hotter and with the wand, you could stick it into the firebox without having to put your head in there!

[boilerman101]

I only clean my primary elbow at the end of each heating season during my final shutdown cleaning and it only has about 1/4 inch of tar creosote in the bottom. I've had my E2400 since 2010 and I don't understand why you would be getting that much unless you are operating with a very deep coal bed, burning unseasoned wood or not allowing it to burn down and dry out. Other possibility could be if the cover on top of that elbow does not seat correctly on top when in not burn cycles. I find nothing but a little dust in the lower secondary elbow ever. I usually get reaction chamber temps of 1,000 - 1,400 degrees each burn cycle...what are you guys getting?

[doctorb]

I am much the same as Boilerman.  I clean my 2300 solenoids once a year. The secondary solenoid doesn't get clogged with creosote at all.  I still check it every year, but have had to do minimal cleaning.  I too use a shop vac for cleaning.  No filter.  when it is turned on you will spray a little ash dust out of the exhaust port, but Im not setting the thing on fire.  I have not used a torch to clean the solenoid.  I use a screwdriver and elbow grease.

[garret]

Boilerman101,
First, I would like to thank you because I have learned much about the operation of my EC2400 by reading your posts.  Between you and Holmes, the info is pretty much spot-on.

In regards to RC temps, I've seen over 1650 F and everything in between.  Hopefully my current recollection doesn't conflict with one of my previous posts.  I'm happy with anything over 1000  F and as long as it is gasifying well with clean emissions and rising water temps.  My metric for performance is how quickly the unit goes from idle to gasification.  This is also an indicator that high temperatures will be achieved during a given cycle.

[boilerman101]

Garret, I'm glad some of my ramblings have helped you and others out.
I agree that reaction chamber temps over 1,000 F means we are gasifying well. However by monitoring operational history charts of my FireStar XP I've learned the importance of correct coal bed depths and how wood size, dryness or even varying times of a wood load burn greatly affect the reaction chamber gasification process on our Eclassics or any other gasser for that matter. I don't believe you can gauge the furnace performance by how quickly the unit goes from idle to gasification as that process can vary greatly. After loading, the first cycles take much longer to reach 1,000+ F than cycles taking place 3 hours or more later and coal bed depth comes into place here as well. On our Eclassics with the automatically monitored secondary air induction, it is amazing to see how often they will hit stage 2 or stage 3 only to have temps fall back as the combustion at that time can't handle that extra air yet, to ramp up to the next level. But when the combustion is ready for it, it takes that additional air and quickly accelerates the burn process and temps jump up 25 - 50 degrees F every 6 second readout. This is why I don't believe that gassers that just throw a constant amount of air through the primary and secondary chambers throughout a burn cycle or fresh wood load to the next wood load period can be as efficient as the Eclassics. CB seems to have this figured out.

[garret]

Unless one is involved in the design and testing of these gasifier-type OWBs, it is difficult to support any hypotheses regarding the observed behavior and nuances of operation.  I totally agree that its all about the coalbed.  There is much to know when it comes to gasification.  An engineer colleague of mine earned his PhD studying underground coal gasification and has spent a large portion of his career perfecting it.  Fortunately my goals are far simpler and less noble:  To reliably and efficiently heat my home (and DHW) using renewables.