Oil burner startup rumble when cold


  #1  
Old 05-10-17, 08:16 AM
G
Member
Thread Starter
Join Date: Mar 2014
Location: United States
Posts: 60
Received 0 Votes on 0 Posts
Oil burner startup rumble when cold

Hi All -

I have an older peerless JO-T HW boiler with a Beckett SR burner that I'm trying to keep limping along until the natural gas main is extended past my house. Right now it ends 2 houses down, and they want over $20K to bring it to me. If I can wait until the neighbors are ready to switch over, it wont cost me a dime. The boiler is responsible for DHW production via thankless coil, but heating duties are shared with a pellet stove. I go through about 500 gallons of fuel oil a year.

The oil burner makes a substantial rumble when starting up after not running for a while. Its a loud whoosh or rumble, like when a BBQ doesn't ignite the first few tries. The rumble is very short lived, only on initial ignition. There is no shutdown rumble. Warm starts seem to be fine, the noise is no louder that normal combustion noise.

I have regularly cleaned the boiler out at least yearly, replaced the fuel filter, nozzle, electrodes, and even the transformer (though it tested fine with the screwdriver). Most recently I added the Beckett 2182602U solenoid valve with a 4 second delay.

The vent stack is pretty simple. The boiler flue pipe has 18" inches of rise, tee'd into 4 foot horizontal section of 6" pipe, appears properly pitched, with a damper on one end and up the chimney on the other. The chimney is 26 feet tall, with what looks like a 4" liner, and a chimney cap.

I've had one HVAC tech in to give it a cleaning and tuneup a few years back, and when asked about the noise he said it was normal for that burner, and to get rid of it, I'd need to replace it with a newer and more efficient gun. This was before I started replacing parts and adding the delay valve myself.

Any ideas what my next steps should be? I really suspected it was fuel oil leakage as the pump spun down, and that the solenoid valve would have done the trick, but sadly no such luck. Thanks for any advice on keeping this ancient beast alive.
 
  #2  
Old 05-10-17, 11:37 AM
S
Member
Join Date: Oct 2013
Location: United States
Posts: 3,249
Received 87 Votes on 81 Posts
What you can try is shut off your power and pull the assembly and see if you have any oil in the tube or signs of oil after drip. The solenoid should have helped your pump seal problem if there was one.

Your assembly may be positioned wrong or your nozzle spray pattern may be wrong spraying oil onto the tube causing an eventual build up that is not burning causing a rumble when the spark eventually ignites it on start up.
 
  #3  
Old 05-13-17, 04:29 AM
G
Member
Thread Starter
Join Date: Mar 2014
Location: United States
Posts: 60
Received 0 Votes on 0 Posts
Hi Spott, Thanks for your response.

I finally got around to doing what you suggested this morning. I got up before the first call for heat, while the boiler was still cool. I pulled the burner first and checked the nozzle depth with the beckett key tool, and it was spot on. The airflow guide / retention head was not caked up or plugged. Then I pulled the assembly out, and while the electrodes were slightly dirty, they weren't horrible. The tube itself was also dirty, but no signs of actual fuel puddling or pooling.

I reset the electrodes just a touch, wiped everything down and reassembled. I flipped the power back on, and watched the burner ignite through the inspection door, and it ignited cleanly without any rumble. Probably because I had just wiped down everything.

The nozzle I have installed is a delavan .75 gph 80* A, which sounds like a reasonable choice. The boiler isn't particularly shallow, but I wouldn't say its deep either, maybe 10 to 12 inches. I should also note that I rebuilt the combustion chamber and target wall last year with the lynn 1067 kit, but the rumble problem has been around since well before that.

As for air settings, the bulk air band is closed, and the airflow shutter is 3.5. If I close the shutter by a half to a full number, the flame slows down and the tips get very smokey. Higher than 3.5 and the flame starts really blasting the target wall. I get plenty of draft through the inspection door with the incense trick - or in my case some smoldering paper towel.

As far as I can tell based on youtube and internet bro-science, everything seems like its where it should be.

Thanks again for your help.
 

Last edited by GuitsBoy; 05-13-17 at 05:24 AM.
  #4  
Old 05-13-17, 10:17 AM
S
Member
Join Date: Oct 2013
Location: United States
Posts: 3,249
Received 87 Votes on 81 Posts
G,
What is the full model number of your boiler. There should be numbers with it also which will tell the size of the boiler. Next, how did you select your nozzle size and spray pattern. What is your pump pressure. Has it been adjusted without a gauge. Some models use a solid spray while others use a hollow. Spray patterns can make a big difference in how the oil is delivered as does the pump pressure.

The tube should not have dirt or anything accumulated in it. It is there to house the assembly and for the air delivery for combustion. There should be nothing on the electrodes as well. If what you call dirty is a coating of black that is an accumulation of carbon which is unburned oil that is not being delivered properly to the chamber.

The new chamber shouldn't be causing any problems unless the fire is hitting it somewhere which will result in unburned oil also. The chamber is there to contain the fire and should not be touched by the flame at all.

If after you cleaned the electrodes the burner didn't rumble when started seems like you may be on the right track. I would keep an eye on it and if it rumbles again in the future or if you're just curious pull your assembly again, now that you know it's clean and see if it's sooted up again. If it is and it rumbles then you must find why they are sooting up. Oil is getting on them somehow and it takes very little to cause problems.

There is no reason for your electrodes to have anything on them if set up right. Maybe your adjustment might do the trick.
 
  #5  
Old 05-14-17, 05:36 AM
G
Member
Thread Starter
Join Date: Mar 2014
Location: United States
Posts: 60
Received 0 Votes on 0 Posts
Hi Spott, thanks again for the response.

The boiler is a Peerless JOT-3H-W, which I assume means 3 boiler sections. Its rated at 125K BTU/Hr gross output, or 108K net. I went with the same nozzle that was already in there when we bought the house. I do not know the pump pressure as I havent bought a gauge yet, but judging by nozzle size I would guess its 100 psi. The burner is a 1725 RPM model, I'm not sure if that has any bearing on possible pump pressures. The oil tank is also in the basement, maybe 15 feet away, with a new looking line. Sorry thats not very specific.

I wouldn't call the tube dirty, but its certainly not shiny and clean. It has I guess some surface rust and dust from a couple decades of being exposed to air. It wont wipe off any cleaner, but its not a sludge or soot. Its how i would expect a burner of its age to look, and not much different from what i see in you tube videos.

Yes, the electrodes had some soot on them, but having run the entire heating season since I had last pulled them, it didn't look too bad. It was just a light smudge, and not nearly to the point where the carbon might ground out and kill the spark. I'm hoping the solenoid will help with this too.

Anyway, whatever magic happened upon reassembly yesterday was short lived, as at least a mild rumble on startup returned a few time throughout the day. Perhaps it has something to do with the inspection door being open at first? Maybe a draft issue?

Thanks again for you help
 
  #6  
Old 05-14-17, 09:14 AM
S
Member
Join Date: Oct 2013
Location: United States
Posts: 3,249
Received 87 Votes on 81 Posts
G,
First let me ask, although a nuisance did you pull the assembly after rumbling and check to see if the electrodes were clean. Next, the size of the motor has no bearing on the pump pressure. That is a separate adjustment on the pump.

As far as your draft issue goes if you don't have a draft gauge one quick way to see if at least you're getting some draft through the boiler is to, with the burner running open the inspection door and put your hand in front of the hole. You should not feel any heat if you are getting a draft. If not you will feel good heat on your hand. In that case you have a draft problem somewhere. Not necessarily from the chimney but possibly a boiler restriction.

Weil McLain was a very tight boiler for it's time and if not set up right had a tendency to plug up quite easily.

Next and this gets a little technical. The specs for your boiler call for an F6 head and a minimum nozzle of .85 x 80A. You have a .75 which is too small for an F6 head. The .75 is fine if it works for you but the head must be changed to an F3. The difference being in the vein spacing which effects the air. The other thing you could do is just try a .85 nozzle.

Just want to mention that even after a year your electrodes should have been clean. When you replaced your chamber your burner tube is not sticking out beyond the wall. It should be back about 1/4" from the end of the wall.

Beckett Model SR Oil Burner Instruction Manual. I googled this, it may help.

This could get involved and long but maybe the manual could help.
 
  #7  
Old 05-16-17, 08:24 AM
G
Member
Thread Starter
Join Date: Mar 2014
Location: United States
Posts: 60
Received 0 Votes on 0 Posts
Hi Spott, thanks again for your assistance.

I pulled the electrodes again this morning, and they were clean. I also tested the transformer, and got at least 3/4" arc with the screwdriver.

I have tested the draft using the burning incense stick trick, and the boiler is pulling the smoke in through the inspection door from at least 4 inches away.

The boiler is a peerless, not a weil-mclain. The first cleaning I gave it required chipping quite a bit of hardened scale and soot. It looked like porcelain or cement, tinged red, over the steel boiler sections. In the years that followed, cleaning has been much easier. There is a little bit of black sooting, but its fairly easily swept down with a brush. In any even, I do not believe the boiler is plugged up, since I have good draft, and cleaned it maybe a tank-full ago.

I have not pulled the burner again to check what head I have, I assume that its stamped onto the airflow guide somewhere, or that I can match it up online somehow. Is there any way to tell externally?

As for the tube sticking past the wall, I'll have to verify it again when I pull the burner again, but I do not believe its sticking past the firebox insulation.

I have read the manual in the past, as well as again now, but didn't really see anything that jumps out at me as being wrong in my installation. Of course I still have to find out what retention head I have.

One thing I noticed this morning is that while the boiler is still relatively cool, the boiler will rumble on startup with the inspection door close, but it will ignite correctly and smoothly if I have it open. I did multiple cycles, and every time I had the inspection door open, it was a clean ignition.

I also tested holding the damper fully open and fully closed, and found no difference between the two. The boiler would always rumble if the inspection door was closed.

Once the boiler heated up (after a few minutes of cycling on and off) the rumble disappeared on start up. It seems once its hot, it ignites properly regardless of the inspection door being open or closed.

Weird.

Thanks again for all your help,
-Tony
 
  #8  
Old 05-16-17, 12:49 PM
R
Member
Join Date: Nov 2011
Location: USA
Posts: 423
Received 3 Votes on 3 Posts
Sounds like you've done a lot of troubleshooting, the types of things I would be doing. Have you ascertained that the flame isn't impinging on any of the combustion chamber walls, per spott's suggestion?

You sound pretty sure about the draft being sound, and what you describe supports that, but I think it would be worthwhile at this point to take apart the flue vent connector piping and check it for obstructions. Several years ago I had an old oil burning furnace start rumbling on startup, and it turned out to be a restricted flue vent pipe...when I went to clean it out I found a pigeon carcass and a lot of accumulated soot inside.

I've heard stories about some of the Beckett burners being finicky and that correct heads, nozzles and electrode adjustments are critical.

Speaking of which, have you ever considered trying another type of oil gun? I see newer Carlin EZ oil burners being sold on eBay and Craigslist for a couple hundred bucks or so, usually the result of an oil-to-gas conversion.
 
  #9  
Old 05-16-17, 01:05 PM
G
Member
Thread Starter
Join Date: Mar 2014
Location: United States
Posts: 60
Received 0 Votes on 0 Posts
Hi Rockledge,

That's a pretty good suggestion, maybe a chimney sweep is in order. There's a screened chimney cap up top, so Id be surprised if a bird carcass was in there, but you never know.

The only section I haven't visually inspected is the chimney liner, otherwise everything else is clean and clear. The rumble has persisted throughout multiple years and cleanings, so I'm not going to bother taking the top of the boiler apart until I clean it out again in the fall.

As for replacing the entire burner, I'm not really against doing that, I just dont have any knowledge of properly sizing and spec'ing out the right one. Honestly, I'm sure just about anything will run better and more efficient than this old burner. It might be something to look into. Any suggestions on where I might be able to read up on how to pick the right burner?

But then again, I dont have any tools to do a proper setup, aside form a high temp thermometer and a stick of incense. Calling out a burner tech without a contract on long island will probably add 300 to 400 bucks to the cost.
 
  #10  
Old 05-16-17, 07:09 PM
R
Member
Join Date: Nov 2011
Location: USA
Posts: 423
Received 3 Votes on 3 Posts
That's a pretty good suggestion, maybe a chimney sweep is in order. There's a screened chimney cap up top...
In my case the problem was not in the chimney flue, but in the exhaust vent pipe that connected the furnace to the chimney.

If your chimney flue has a cap, then I doubt your going to get birds/critters in there. In light of that, I doubt a chimney cleaning would help things all that much.

As for replacing the entire burner, I'm not really against doing that, I just dont have any knowledge of properly sizing and spec'ing out the right one. Honestly, I'm sure just about anything will run better and more efficient than this old burner. It might be something to look into. Any suggestions on where I might be able to read up on how to pick the right burner?
Great question. But I don't have a good answer for you. I'm not a heating technician so I don't have any personal insight to pass along. Do you have the Installation/Operation manual for the Beckett burner? I'd think there would be some info regarding burner/nozzle/etc. sizing in there...
 
  #11  
Old 05-17-17, 12:00 PM
S
Member
Join Date: Oct 2013
Location: United States
Posts: 3,249
Received 87 Votes on 81 Posts
g,
My one suggestion would be and probably the simplest and cheapest is to try an .85 80*A nozzle in case you do have an F6 head which is what that boiler says the burner came with according to OEM specs. The number would be stamped on the head itself but probably no where else and it could have been changed.

The F6 head will accommodate .85 - 1.10 gph nozzles. For a .75 you need an F3 head. The difference in the heads is the vein spacing which regulates the air. If they put a .75 nozzle without changing the head no matter what you else you adjust the air will never be right and will be too much for the .75.

You said that was there when you came and you've had the rumble. For short money you can eliminate that cause without removing the burner or replacing the head.

You have done so much work to your burner at this point I don't think another burner is immediately needed but if you choose to go that route any burner will work for you that accommodates your firing range and they all do. The important things are tube length and how they mount up to your boiler. Separate tubes can be bought and they come complete with the assembly in them.

The burner you have is a retention head burner with a 1725 rpm motor. The only difference is the new ones are 3450 rpm now. If you want a Beckett, just get a Beckett AFG burner and you will be fine.

Hope this helps a little.
 
  #12  
Old 05-22-17, 06:50 AM
G
Member
Thread Starter
Join Date: Mar 2014
Location: United States
Posts: 60
Received 0 Votes on 0 Posts
So I swapped the nozzle to the .85 80* A, and it was WAY too much. The flame was BLASTING the target wall no matter where the air was. Even if I pulled it back to the point it was smoking heavily, the flame was still hitting the target wall. I wasn't about to leave this nozzle in there, so I swapped it back out to a new .75 nozzle. Even with this nozzle, same size as what I had been running, the flame is just licking the target wall. I dont see any sparkles, but it still seems like the flame has more throw than the last nozzle of the same size. Anyway, I adjusted the air for the best compromise of just past smoky tips, but without blasting against the target wall.

I guess the next thing to check is the pump pressure. I adjusted a couple turns both higher and lower, and neither made enough of a difference to give me that "Eureka!" moment. I ordered a oil pressure gauge, and it should arrive in the next day or two.

Spott, can I ask where you found the burner specs for the JOT-3H boilers? I cant find any information on them anywhere.
 
  #13  
Old 05-22-17, 11:01 AM
G
Member
Thread Starter
Join Date: Mar 2014
Location: United States
Posts: 60
Received 0 Votes on 0 Posts
If I decide to go with a new AFG, theres a good deal on a brand new gun on ebay, but its for a burnham boiler. Are all AFG models the same, meaning can I simply swap out the blast tube and mounting flange for the one that fits my boiler? I would of course step down to an F3 head and .75 GPH nozzle, and drop the pump to 100 psi and go from there.

For that matter, why are blast tube lengths chosen? I have a long one, probably a 13" blast tube. Do I need to keep the same length?
 
  #14  
Old 05-22-17, 11:05 AM
S
Member
Join Date: Oct 2013
Location: United States
Posts: 3,249
Received 87 Votes on 81 Posts
g,
https://www.beckettcorp.com/

Click on Support. From the menu click on OEM SPEC GUIDES. Then Residential Oil.

That will pull a section with all different boilers. In the search bar type in your boiler. PEERLESS. not the model number, just PEERLESS.

It will bring you to PEERLESS boiler models. If you scroll down and click on page 3 it will have your model number.
Peerless Heater
JO/JOT3H or JO/JOT3L.

The difference between the two models is the difference in BTU'S due to the firing rates. It's just using a different nozzle but is the exact same boiler.

You want the 3L boiler since you are using the smaller nozzle already.

What they call for is listed there. If you click on the (+) sign it will give you the air settings also.

On a side not Peerless is calling for a Beckett AF burner and you said your is an SR. If you look in the column marked burner you will see what they want. There are a couple of boiler models on page 5 but they are much larger models with a higher pump pressure also. I don't know if your burner was switched out at one time but it just doesn't match with the specs.

About the pump pressure. Until you get the gauge I wouldn't play with the pump. It take very little movement to adjust the pressure. If you went 2 turns you are probably way too high. It says you want 100 psi.

https://heatinghelp.com/heating-muse...uction-manual/

This is the link for your burner you can download to see what they want.

Hope this helps a little.
 
  #15  
Old 05-22-17, 11:26 AM
G
Member
Thread Starter
Join Date: Mar 2014
Location: United States
Posts: 60
Received 0 Votes on 0 Posts
Wow, so the burner was spec'ed for an AF burner with a 4-1/2 air tube? What I have currently installed is way off, with the older SR and a 13" blast tube. Pretty sure I have an f-3 head in there from the looks of it.
 

Last edited by GuitsBoy; 05-22-17 at 01:32 PM.
  #16  
Old 05-22-17, 01:31 PM
S
Member
Join Date: Oct 2013
Location: United States
Posts: 3,249
Received 87 Votes on 81 Posts
g,
The air tube length is flexible as long as it is set up right. Had you mentioned your current 13" tube that may have simplified things and answered a lot of questions I had. I know of no boiler/ burner combo that comes with a 13" tube or would anyone replace a spec tube with that size if they were just replacing the tube.

My guess is that is not the original burner but a replacement that someone had laying around and just threw in.

The AFG will work for you. The tubes come in different lengths and are sold separately if needed. They come complete with the proper size assembly for the tube and the heads are also sold separately for your firing rate. Just make sure you match your head with your firing rate.

If you are happy with the .75 get an F3 head. That will give you a range from .75-1.25 gph. That way if you want to increase you can or stay at .75. With the F6 .85 is your low end and too big for your current situation.
 
  #17  
Old 05-22-17, 01:36 PM
G
Member
Thread Starter
Join Date: Mar 2014
Location: United States
Posts: 60
Received 0 Votes on 0 Posts
Anyway, I used an ebay coupon and got the AFG burner for 225 brand new, then ordered the 4.5" air tube combo, and a new flange and gasket for an additional 57 bucks. Thats 282 total for a brand new relatively modern burner, controls, transformer and cleancut pump.

I'm hoping I made the right move going with the shorter air tube, but I think that will get me closer to what was originally spec'ed for my boiler, although Ill use an f3 head instead of the f6.

The only other concern I have is that some people state that the AFG may produce too high a static pressure for an older loose boiler. But others still say it's fine. I cant imagine it being any worse than what I've already got on there, and it will be nice to have all new parts.
 
  #18  
Old 05-22-17, 01:43 PM
G
Member
Thread Starter
Join Date: Mar 2014
Location: United States
Posts: 60
Received 0 Votes on 0 Posts
Spott, Thank you so much for all your help. I really appreciate you taking so much time to help me out.

Ill let you know how the new burner works out.

Thanks again.
 
  #19  
Old 05-23-17, 10:15 AM
S
Member
Join Date: Oct 2013
Location: United States
Posts: 3,249
Received 87 Votes on 81 Posts
g, I've got a 34 yr. old Weil McLain with an AFG burner. You will be fine. As long as the tube is long enough. Remember the flange will take up some room, so as long as the tube is long enough to be mounted on the burner with the flange and get properly positioned in the chamber it will work.

Good price for a new burner.
 
  #20  
Old 05-29-17, 10:21 AM
G
Member
Thread Starter
Join Date: Mar 2014
Location: United States
Posts: 60
Received 0 Votes on 0 Posts
New AFG burner is in, and first starup was darn near silent. Ill let you know how it goes after a few days, but I have high hopes...
 
  #21  
Old 05-29-17, 10:28 AM
S
Member
Join Date: Oct 2013
Location: United States
Posts: 3,249
Received 87 Votes on 81 Posts
Congrats. Sounds promising.

Good luck,

SKIP
 
 

Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description:
Your question will be posted in: