Baffle Plates Rotting away and warping.

ChasMan

Just finished up cleaning out my Slant Fin EC13 for the year. I had a heck of a time removing one of the baffle plates. It appears to have been warped due to heat. This unit is about 10 years old now I guess. Do the flue baffles rot normally? Here is a pic of the baffle. You can see the rot at the bottom and the slight curve in the shape. I just ground it flat and stuffed it back in. Last I looked at it was about 2 years ago, almost 3. It had a bit of rot on it then but not much.

Jamie Hall

Flame impingement? Have the burners been properly adjusted? Pressure? Draught? Air? All by test instruments -- not by eye?

GBart

that isn't rot, it's heat damage, they will eventually disintegrate from the heat of the fire

ChasMan

Ok, I thought something might be wrong. It didn't do this for the first seven years of its life then all of a sudden... This is a very difficult boiler to set up. Slant fin says 3.75 on air and I have it set to 2.4, any more than 2.6 and it is soot city. I'll start with the basics again. The first baffle looks fine it is the second and third that are messed up. Flame is a bit long, the turbulator may need a slight tweak. Of course my meter needs calibrating again. I hate this boiler.

Jamie Hall

There is no way to set a burner without the test instruments. Something is wrong with your numbers on air.

ChasMan

You mean the 3.75 / 2.4 numbers? Those are correct. Those are the Riello air gate settings I was referring to. The way I was taught to set it up was by Slant Fin. They say to set it to 3.75 to start and then adjust for a bright fire without smoke or oil stain. Set the DRAFT REGULATOR to obtain 0.51 – 1.02mm (.02" – .04") draft at the breeching. Following that I am about 2.6 on the air gate and that's where Slant Fin and I had to separate because the smoke paper does not lie and Slant Fin can't understand why I can't get zero smoke before that. I studied this boiler. Dedetrich makes the casting and when they were selling it directly they had a totally different setup for insertion tube length / depth and air gate. It made me question Slant Fin's set up instructions. So, I use the 2.6 and adjust to 12% CO. It has been a couple of years since the last time I set it up with instruments. I will check the fuel pressure and what not soon.

Jamie Hall

Do what you can with it, but what I'm seeing is evidence of flame impingement on that plate -- which shouldn't happen. Something is amiss.

ChasMan

Thanks Jamie. I opened up the air setting a notch for now. Threw my back out so not interested in messing with it much. This thing has been a disaster since day one and little help from Slant Fin or Riello. Original installer no longer returns emails. So kind of left on my own to mess with it. Whenever it fails I am sure it will be in the middle of winter and the oil company will replace it with a pinner.

Steamhead

@ChasMan , what nozzle are you using? What pump pressure?

Reason I ask is because the spec I found in the manual is quite unusual for a Riello. Unlike most Riello 40-series specs I've seen, which call for 60° solid-cone nozzles like the Delavan B series, this one calls for an 80° hollow nozzle- a Delavan A, 0.55x80A to be exact. I'm assuming this is because of the shallow firing zone.

Beckett and Carlin also have burner specs for these boilers, using hollow or semi nozzles in the smaller sizes. Carlin's spec for the EC-13 calls for a 45° hollow nozzle. I don't think I've ever used a nozzle with this pattern.

The manual is here:

http://www.slantfin.com/wp-content/uploads/2015/11/Eutectic-10-Series-Installation-and-Operating-Instructions-1116.pdf

ChasMan

At present I am using the .55 80a delevan at 140psi as in the manual. I agree it is weird. Dedeitrich used the long burner tube instead of the short when they sold them but most settings were similar except the air.

ChasMan

I know I am not the only one with these issues but whatever the secret sauce is to making these units work remains elusive to me.

ChasMan

The dedeitrich was a .55x60a @135 psi with a 2.5 air gate.

EBEBRATT-Ed

Setting the air gate to 2.5 or whatever means nothing. Manufacturer settings are a starting point and are sometimes meaningless.

Reason being some manufacturers don't do adequate testing.

You need to use combustion test equipment

Fuel temp & pressure air temperature and density changes and altitude change everything

ChasMan

Just for completeness, Detetrich used a 3 inch insertion depth instead of 5" like slant fin.

ChasMan

@EBEBRATT-Ed Yes, but how many hours can a tech spend getting it to run right? Slant Fin told me not to run it like this. So I guess I should have a basement full of soot as that's what happens. With the air gate shut down we get a wide range of stack temps and good co kn readings up to 88 pct efficiency it will even condense but now we have flame impingement. I suspect that is the turbulator set too high. I set it to 1.0 as per manual. I had it at zero to help with light off and after increasing the spark gap I found I could open the head setting so that's the only thing I changed.

STEVEusaPA

If you know what your doing you don’t need hours. You’re opening this, closing that, changing the other thing.
Without the proper tools and skills you’re just guessing and trying to get lucky.
Seems like it was working fine for 6 or 7 years until you decided to work on it.
The 'secret sauce' your looking for is experience. You should find someone who has it.

You’re not getting help from Riello or Slant Fin because they prefer to help knowledgeable professionals.

ChasMan

When the experts from the mfg. set it up it wouldnt even stay running. My installer, a Wally no less, left it to put soot all over the basement. At least I got it to run. Can you explain how to set the tirbulator properly in your expert opinion? When does it need to be changed from factory spec? Did I offend you in some way Steve? I get lots of help from pros just nothing that works. Slant Fin claims they did the work to come up with the settings in the manual and very little adjustment should be required. Several folks have had issues with smoke at these settings, myself included. Now we are seeing long term flame impingement damage. How should we approach this issue? Call Slant Fin? Will they treat this issue the same way? Shrug their shoulders and say they never heard of it before? Or should we just roll the dice on another professional. Genius level professional stuff. Way to go Steve. You do not know the history of this installation yet you think I am changing all kinds of things without instruments or training or experience. None of that is true.

Jamie Hall

@ChasMan -- seems to me you're neither looking for help nor advice, but a victim to point out and a way out of a mess. Good luck.

STEVEusaPA

No I'm not offended. I believe you are truly frustrated and every attempt by anyone you had so far hasn't worked out, so you are trying to take things into your own hands. Perfectly normal.

The problem is it's not a job for someone without the proper skill set, tool, experience. And you haven't found that someone yet.
I don't recall you ever saying where you are located. Maybe someone else on the Wall can help you or recommend someone.

My feeling is if the proper person were to go over the entire burner and boiler, they would find the problem.

The trouble with trying to help you online is we all are just guessing. Moving the air band one number could be the difference between sooting and not sooting.

Moving the head 1 or 1.5 could be the difference between 0 CO and 500 CO.

It's possible you're not using the smoke gun correctly.
It's possible your analyzer isn't correct.

You yourself said:
"...It didn't do this for the first seven years of its life then all of a sudden... This is a very difficult boiler to set up..."
So..what changed?
How's combustion air? Enough? No high efficiency dryer sucking out all the combustion air?

Keep in mind when adjusting air, opening and closing may not do what you expect if you don't know which side of the stoichiometric curve you are on. This is why most experts recommend after steady state, and setting the draft, (-.02 to -.04 at the breech for your burner/boiler), close the air band 2 numbers and immediately taking a smoke test. If you're not on the black sooty side, keep closing. Usually if you are, you can't even get 3 pulls on the smoke gun. Then work your way back up to true zero smoke. Then see what the analyzer has to tell you. Then and only then can you tweek the turbulator setting, while watching your analyzer. If you have to move it more than 1 number setting, you should go back to the smoke gun and make sure you are still at true zero smoke.

Proper way to use a smoke gun...
No paper in, close knob, put thumb over the end, pull plunger. If you can pull a full stroke, something is wrong with it. You should only be able to pull about 2" and have it hold.
Put in paper properly.
3 seconds for complete pull, 1 second pause, 3 seconds to return, 1 second pause. 10 total pulls.
I see people pumping like they are trying to pump up a basketball, which is incorrect.

When I look in the manual I see starting positions of "1" for the head and "3.75" for the air band, for a F3, .65X80 A nozzle.
There's also notes about sealing the joint between the flange and air tube with high temp sealant.

Here's how I would probably approach it:
-Completely take the boiler apart, remove the baffles, swing open the door and make sure it's clean. I'd also check the flue pipe, chimney base and look up the chimney to make sure it's clear (unless it's BF or direct vent).
-Change the nozzle and verify the nozzle assembly is correctly installed and set to the correct dimension.
-Check/clean blower wheel (good luck if it's dirty, it's not easy to pull a motor).
-Check the insertion depth and make sure the end of the air tube isn't burnt, cracked or warped. I'd also make sure it's properly sealed.
-Close it all back up and make sure all the gaskets, door seals, cleanout seals are good and properly installed.
-Change the pump strainer and check the quality of the oil.
-Put all settings back to their starting positions.
-Properly bleed pump, confirm pump pressure.
-Perform full combustion test as outlined above.

Doing all of that has to fix it, if (IF) you know what you are doing, how to do it, and how to interpret the results.

If I'm not mistaken, I think THE leading expert (in my and many peoples opinion) has that same boiler, and has spoken wonderfully about it's performance.

So where are you located? Let's see if we can find the right person to make this nightmare of yours (and my typing hands) go away.

ChasMan

Thanks,

I am located in Danbury Connecticut. I called lots of local people here several years ago, none of them used digital instruments at the time. The only people I have ever had willing to look at it are the original installer, (he thought Slant Fin had a disaster on its hands), the fuel oil dealers who are useless and Slant Fin who was calling it in with a local Petro tech at the time who was also useless but they at least tried for a while and I appreciated that someone was making an effort at least. This would have been circa 2010 or so. The installation is from fall 2008. In the end Slant Fin seemed to blame my venting which is a 22 foot tall five inch SS corrugated liner recommended by the installer. They felt it should "probably" be a 6" straight liner and preferably insulated. They made this suggestion in the summertime btw.

Speaking of draft, I keep the draft low, -.015. This gives me slight positive over fire draft of 0.05. Slant Fin thinks -.04 is ok, This produces a negative over fire draft and sucks the flame off the retention head. This casting was designed for positive pressure. Hence the need to seal the blast tube to the flange. My old self would say, How stupid can a manual get? I am trying to be more tolerant now. Slant Fin also felt that I "may" have too many 90's in the vent pipe. I have one extra 90 (three total) due to the configuration of my basement. I could fix that with some blasting I suppose. The house is on ledge. I replaced the three 90s with six 45s to smooth it out as much as possible. It made no difference. Beyond making custom pipe, I cannot improve it. So, to me Slant Fin became a dead end of no help and just wanted to blame everything but their equipment. I understand that sort of. Its the basic business model of residential construction. Anyone who owns a home has dealt with this same type of issue at some point.

So, this is when I invested in an analyzer, fuel pressure and draft gauges, smoke test kit, nozzle wrench. I bought Several books. I read up on the stochastic curve and combustion testing. I read the Riello handbook, I learnt, everything I could in great detail and asked many questions. I did lots of trial and error work, nozzle size and pressure changes, filtration upgrades, tiger loops, combustion blankets, the list goes on. In the end, I (me moi myself) managed to get rid of the hard start and the heavy soot and get good efficiency numbers and a clean burn and a reliable system. I would be hard pressed to go at it again with another pro unless they had seen and fixed this type of issue previously. I am certainly not going to accept a bill for setting the air band to 1.8 and saying I need a new chimney liner.

Also, and sincerely, thanks for the detailed explanation of smoke testing. I have a Wohler smoke tester, the hand pump type. It came with fairly detailed instructions about how to pull a sample. But, when I am talking soot here at the factory settings, I am talking about blow it out the barometric damper into the room soot. I don't need to even test for that. I can see it and clean it up off the floors for a week on my hands and knees. And every time a pro wants to bring it back to factory spec we will get that experience again. You can literally see the soot floating off the flame inside the chamber. Not exactly confidence inspiring.

Anyways, I think I may have just messed up the flame shape by setting the turbulator without paying attention to the flame shape. My Bad. It was a few years ago so my memory is not that clear and I didn't keep a record. I think what happened is that a widening the electrode gap in an attempt to smooth out the lightoff was met with so much success that I probably just tried opening the turbulator as per the manual to see how it lit. And then, like an idiot, forgot about it. Previously, I have moved the turbulator from 0 to 1 and seen no difference in CO for a given air gate setting so there really isn't that much of a worry in my mind about that.

So I can not see the flame very well right now anyhow as the viewport is tough to see in. You look down at an angle and the back wall is not completely visible. I don't have a flame mirror, been meaning to get one. I don't see any impingement. For now I will just set the flame a little smaller and get my analyzer calibrated so I can do another setup. Its been a couple of years since I last did it. I am not familiar with flame impingement damage. I do not know how it progresses. The metallurgic process of it escapes me as I am sure it does many others. Does this sort of damage happen slowly? Does it take a long time for the metal to get to a point where it starts to disappear? We all know there are invisible flames that cannot be seen with the naked eye. Slant Fin moved the burner tube in a couple of inches into what's already the smallest chamber in the industry. This made it easier, no doubt, to get impingement. Its quite possible that this will happen to all of these boilers eventually. I would hate to chase this issue around for five years like I had to the ignition and combustion issues. I can also note that there doesn't appear to be any damage to the flue passages. It appears to be limited to the baffles. I guess it could be overfired from the last nozzle change.