Beckett AFG burner won't fire, techs no help

Reply

  #1  
Old 10-20-09, 04:11 PM
Member
Thread Starter
Join Date: Apr 2009
Location: New Hampshire
Posts: 13
Upvotes: 0
Received 0 Votes on 0 Posts
Beckett AFG burner won't fire, techs no help

For the past year I've have issues with my Beckett AFG not firing and several service calls have resulted in lots of replaced parts but no solution.

Here's the symptom: the burner gets power, motor/blower/pump spins, but no flame. One reset usually gets it started and it always runs a full cycle with a good flame and no other issues. Safety trips multiple times per day.

Here's what's been replaced/adjusted so far.
new pump
new transformer
new electrodes
new nozzle (several)
new filter
new pump screen
Unit has also been serviced/cleaned

This burner started having problems last winter. No flame issue would appear at intervals from once every few weeks to several times/day. Most of the service calls/replacements happened then. After electrodes were replaced that seemed to solve the problem and the burner has been working without any issues since last February( it supplies domestic hot water via a zone which heats a SuperStor tank so the burner/boiler does cycle a few times a day throughout the warmer months).
As soon as it got cold again last week and the boiler started running more frequently the same problem came up again, motor runs but no flame.
So far this week I have done the following: replaced the filter, pump screen, electrodes, and nozzle. I have also bypassed the solenoid oil shutoff valve to make sure it was not faulty/sticking. I have pulled the burner and tested to make sure that oil is being atomized at the nozzle. I have also verified that the spark is strong and is jumping the electrodes at the tips. I have also played with the air adjustments. So far, no luck, everything looks normal but a high percentage of the time the burner still won't fire without resetting one or more times. Once it fires, it runs a normal cycle with good flame. Then it won't fire on the next cycle and the safety trips again.
One clue which may or may not mean something; the burner had this problem last winter, but ran all summer with no problem. As soon as the weather got cold and required heat for the house the problem started again.

As I mentioned several techs have made various part replacements but I've still got a malfunctioning unit, any suggestions? I'm at my wits end and am about ready to just buy a new burner (this one is only 8 years old).
 
Sponsored Links
  #2  
Old 10-20-09, 05:07 PM
Grady's Avatar
Forum Topic Moderator
Join Date: Jan 2005
Location: Delaware, The First State
Posts: 13,928
Upvotes: 0
Received 0 Votes on 0 Posts
Too many parts

Parts are being thrown at this burner like politicians throw money at a problem hoping it will go away.

What is the make & model of the furnace? I can probably find the OEM specs for the buner. Once the correct set-up is verified we can go from there.
 
  #3  
Old 10-20-09, 05:36 PM
Banned. Rule And/Or Policy Violation
Join Date: May 2007
Location: Wisconsin
Posts: 8,629
Upvotes: 0
Received 0 Votes on 0 Posts
It is interesting that if all you say is working - the question become why resetting it then makes it always go.

Could it be that you are drawing air, sometimes, at first. Like the pump is cavitating in air, until it about finally catches it's prime?, but by then shuts down on safety? But then a reset gets it going since it almost primed back and was almost ready to fire the first time?

You wouldn't think it be a plugged tank vent since you say that once it does go, it runs for the whole cycle.

I was considering a possible downdrafting issue as well, where after it shuts off and gets cold, there is reverse drafting going on. That can cause carbon to even form on electrodes and possibly send current to a ground path other than through sparking at electrode tips. How did the old electrodes look when you took them out?

If it is because of something out of factory spec adjustment, then why should resetting it ever get it to go? Hence my theory,... unless it is something really marginal, I guess.
 
  #4  
Old 10-20-09, 05:37 PM
Member
Thread Starter
Join Date: Apr 2009
Location: New Hampshire
Posts: 13
Upvotes: 0
Received 0 Votes on 0 Posts
It's a Slant Fin Liberty boiler. I do have the original manuals that came with the boiler/burner. It was a replacement that was installed about eight years ago.
 
  #5  
Old 10-20-09, 05:46 PM
Member
Thread Starter
Join Date: Apr 2009
Location: New Hampshire
Posts: 13
Upvotes: 0
Received 0 Votes on 0 Posts
ecman51, The seven year old electrodes, replaced last winter, were clean but the points were worn(as would be expected). The electrodes installed last winter were clean and pointed when I checked this week. The hot start/cold start issue is an interesting one. This unit worked all through the summer when it only started a few times a day i.e. it would have been cold each time. Now, with the cold weather, it is starting more often and the boiler water and perhaps the burner is somewhat warmer when it starts. Never heard of a hot start issue with a burner, though. Of course the outside air is also colder now and there could be a stronger downdraft. The chimney is very tall, probably 40' from furnace to top so the downdraft could be significant.
 
  #6  
Old 10-20-09, 07:25 PM
Member
Thread Starter
Join Date: Apr 2009
Location: New Hampshire
Posts: 13
Upvotes: 0
Received 0 Votes on 0 Posts
A couple more thoughts/inconsistencies. I don't think the pump priming suggestion will hold. When the safety pops and I reset, there is a lot of smoke from the chamber which leads me to believe that oil was being delivered during the first try.

I was checking the electrode settings again for the nth time and I noticed an inconsistency between the manual that came with the burner and the gauge that came with the Beckett replacement electrodes. The burner has an F48 head BTW.
Manual Gauge
Above 14/32 10/32
in Front 4-5/32 2/32
Apart 5/32 4/32

The apart number differences are probably insignificant but the other differences are bothersome. Anyone have any advice or comments on the significance?
 
  #7  
Old 10-20-09, 07:45 PM
Grady's Avatar
Forum Topic Moderator
Join Date: Jan 2005
Location: Delaware, The First State
Posts: 13,928
Upvotes: 0
Received 0 Votes on 0 Posts
F48?

I've never heard of an F48 head. What's the firing rate? Use the gauge settings except the gap should be 5/32.
 
  #8  
Old 10-20-09, 08:23 PM
Member
Thread Starter
Join Date: Apr 2009
Location: New Hampshire
Posts: 13
Upvotes: 0
Received 0 Votes on 0 Posts
Checked the burner label with a magnifying glass. The head is an F4S not F48. The nozzle is a 1.0 80A.
 
  #9  
Old 10-20-09, 09:22 PM
Member
Join Date: Feb 2007
Location: Brantford Ontario Canada
Posts: 117
Upvotes: 0
Received 0 Votes on 0 Posts
Originally Posted by freesteamin View Post
A couple more thoughts/inconsistencies. I don't think the pump priming suggestion will hold. When the safety pops and I reset, there is a lot of smoke from the chamber which leads me to believe that oil was being delivered during the first try.
There is a possibility that you're not getting the "correct" amount of fuel to ignite, but still loading the combustion chamber. To eliminate a fuel problem, put a clear tube on the bleeder and next time you have to reset, bleed some fuel and see if it's solid fuel and not foamy.

Did any of the techs that were there use fuel pressure gauges and combustion test kits?
 
  #10  
Old 10-21-09, 05:34 AM
Member
Thread Starter
Join Date: Apr 2009
Location: New Hampshire
Posts: 13
Upvotes: 0
Received 0 Votes on 0 Posts
I have bled the pump a couple of times this week. Ran out almost a pint on the last try. Clear fuel, no foam or bubbles.
I didn't watch all of the techs every time but never saw any of them use test equipment.
 
  #11  
Old 10-21-09, 07:05 AM
asm660's Avatar
Member
Join Date: Aug 2009
Location: Punta gorda Fl.
Posts: 62
Upvotes: 0
Received 0 Votes on 0 Posts
Grady I like that Parts are being thrown at this burner like politicians throw money at a problem hoping it will go away.!!!

Why afg will go into safty .

we will look at the easy things most over looked

1 is the fan dirty?
2 air gate in side and out is it clean ?? some units have a baffell in the fan latter modles doint have it.
3 is the pump coupling slipping?
4 is there a tranfsomer gaskett? is it oil soaked???
5 Electrodes ?? what was replaced??? the rods? or the porcelions??
*note if the pocilions loose there shine there useless *
6 what is the over fire draft? you need a draft gage to set up is the draft reg locked closed??
7 did the service teck check the tranfsomer?? you realy need 12000 v min
8 pump pressure is set at ???
9 nozzel ???
nozzel set up you will need a afg tee gage to check the blast tube.
William
 
  #12  
Old 10-21-09, 10:54 AM
Banned. Rule And/Or Policy Violation
Join Date: May 2007
Location: Wisconsin
Posts: 8,629
Upvotes: 0
Received 0 Votes on 0 Posts
Originally Posted by freesteamin View Post
When the safety pops and I reset, there is a lot of smoke from the chamber which leads me to believe that oil was being delivered during the first try.

No further comment on my end, since you are in very good hands with people giving highly technical advice. But if you post problems in the future, please post any relevant clues like this right away. Hope you get'er fixed, and for reasonable.
 
  #13  
Old 10-21-09, 01:33 PM
Member
Thread Starter
Join Date: Apr 2009
Location: New Hampshire
Posts: 13
Upvotes: 0
Received 0 Votes on 0 Posts
Ecman, thanks for the help.

asm660,

1. the fan is clean, not a speck of dust.
2.air gate is clean. This unit does have a baffle.
3.need to check the coupling.
4.There is a gasket around the edge of the xformer. It is not oil soaked.
5. The electrode rods and porcelains were replaced.
6. I don't have any draft testing equipment. Will have to call a tech to check this.
7. Don't know if the tech last year checked the old xformer. He did install a new one.
8. Pump pressure was set to 100 when replaced last winter.
9. Nozzle is a 1.00 80A. I did get a t gauge with the Beckett electrode kit and verified that it is centered in the blast tube and set back from the retention head the proper amount. Is that what you meant?

Thanks for the tips. I'll check the coupling tonight and report.
 
  #14  
Old 10-21-09, 02:42 PM
Banned. Rule And/Or Policy Violation
Join Date: May 2007
Location: Wisconsin
Posts: 8,629
Upvotes: 0
Received 0 Votes on 0 Posts
Originally Posted by freesteamin View Post
6. I don't have any draft testing equipment. Will have to call a tech to check this.
Hey guys,

Is there a homemade or simple DIY way where "free" at least can tell if this is really the issue or not? Kind of like how a mechanic can time an engine without a timing light, within reason.

The objective is to find out what is REALLY causing his problem, without necessarily getting to the absolute fine-tune stage yet. There must be a fairly common problem why he is getting spray, has spark, yet no fire...but does on reset(if I'm on the right thread).
 
  #15  
Old 10-21-09, 03:01 PM
asm660's Avatar
Member
Join Date: Aug 2009
Location: Punta gorda Fl.
Posts: 62
Upvotes: 0
Received 0 Votes on 0 Posts
The baffel can be fun to get back in as well is the plastic cover with the 2 small screws Tee gage must be for an afg this one will just fit in the end cone it will also have makings on it for a beckett 2 burner also what end cone do you have #m please William
 
  #16  
Old 10-21-09, 03:27 PM
Grady's Avatar
Forum Topic Moderator
Join Date: Jan 2005
Location: Delaware, The First State
Posts: 13,928
Upvotes: 0
Received 0 Votes on 0 Posts
Model Number

In order to find the original set-up data I need the model number off the boiler data plate.
 
  #17  
Old 10-21-09, 04:30 PM
Member
Join Date: Feb 2007
Location: Brantford Ontario Canada
Posts: 117
Upvotes: 0
Received 0 Votes on 0 Posts
Originally Posted by ecman51` View Post
Hey guys,

Is there a homemade or simple DIY way where "free" at least can tell if this is really the issue or not? Kind of like how a mechanic can time an engine without a timing light, within reason.

The objective is to find out what is REALLY causing his problem, without necessarily getting to the absolute fine-tune stage yet. There must be a fairly common problem why he is getting spray, has spark, yet no fire...but does on reset(if I'm on the right thread).
Hi Ecman

There are too many variables to set up the burner without the proper equipment.

Some boilers are really fussy on settings. Some some require positive overfire draft, some negative etc. I'll bet that's why Grady is looking for model numbers.
 
  #18  
Old 10-21-09, 04:41 PM
Member
Join Date: Feb 2007
Location: Brantford Ontario Canada
Posts: 117
Upvotes: 0
Received 0 Votes on 0 Posts
Originally Posted by freesteamin View Post
I have bled the pump a couple of times this week. Ran out almost a pint on the last try. Clear fuel, no foam or bubbles.
I didn't watch all of the techs every time but never saw any of them use test equipment.
Hi

Flame needs 3 things to burn properly. Fuel-ignition-air.
Take one away and no fire. Looks like you have covered
your bases as to fuel and spark as much as you can.
If the techs haven't been using test equipment, there's no way they can be sure the burner is set up right. Assuming all the parts you put on are ok and the electrodes and fuel pressure is good, I think I'd be looking at the airgate settings next. Unfortunately this is beyond the realm of the diyer.

My opinion is that you need to find a tech that has an electronic combustion tester and have him come and make
sure the draft and excess air and all that good stuff is right.
 
  #19  
Old 10-21-09, 06:20 PM
Member
Thread Starter
Join Date: Apr 2009
Location: New Hampshire
Posts: 13
Upvotes: 0
Received 0 Votes on 0 Posts
I checked the pump coupling, it appears to be tight.
Re the question about the xformer voltage. I can't check the voltage but, as I mentioned, I pulled the burner and visually checked the spark across the gap with the burner running (with the oil shut off and removed of course) and the spark looked strong and continuous.

The boiler is a Slant Fin Model L-30P.

I understand the comments about getting a tech with the proper equipment. So far my experience has not been good, the techs have been mostly parts substitutors. Guess I'll have to keep looking for a good one. As suggested in one of the posts I was just trying to eliminate the intermittent problem which are always difficult for a tech to see during a service call before getting someone to do the final adjustments.
 
  #20  
Old 10-22-09, 02:45 PM
Grady's Avatar
Forum Topic Moderator
Join Date: Jan 2005
Location: Delaware, The First State
Posts: 13,928
Upvotes: 0
Received 0 Votes on 0 Posts
Slant Fin

The static disc on the nozzle tube should be 2 3/4" & according to Beckett's OEM Spec Guide, the nozzle should be a 1.00-80W, the pump pressure should be 100#, a delayed oil valve is supposed to be there, the air shutter initial setting is 9 & the air band setting is 0.
 
  #21  
Old 10-22-09, 02:57 PM
Grady's Avatar
Forum Topic Moderator
Join Date: Jan 2005
Location: Delaware, The First State
Posts: 13,928
Upvotes: 0
Received 0 Votes on 0 Posts
ecman51

Originally Posted by ecman51` View Post
Hey guys,

Is there a homemade or simple DIY way where "free" at least can tell if this is really the issue or not? Kind of like how a mechanic can time an engine without a timing light, within reason.
There's no way of which I'm aware to make a draft gauge to measure draft down to .01" water column.
 
  #22  
Old 10-22-09, 08:08 PM
Member
Thread Starter
Join Date: Apr 2009
Location: New Hampshire
Posts: 13
Upvotes: 0
Received 0 Votes on 0 Posts
Originally Posted by Grady View Post
The static disc on the nozzle tube should be 2 3/4" & according to Beckett's OEM Spec Guide, the nozzle should be a 1.00-80W, the pump pressure should be 100#, a delayed oil valve is supposed to be there, the air shutter initial setting is 9 & the air band setting is 0.
Grady,
The nozzle and pump pressure are right on. I'm not sure about the static disk measurement though. What does the 2 3/4" refer to? In looking at burner instruction literature I don't see any measurement like that.
 
  #23  
Old 10-23-09, 08:53 AM
Banned. Rule And/Or Policy Violation
Join Date: May 2007
Location: Wisconsin
Posts: 8,629
Upvotes: 0
Received 0 Votes on 0 Posts
Is that perhaps the term for what diffuses the fire coming out of a gun, into the combustion pot? My single gun gas furnace at home has such a plate out in front of the burner. Maybe the 2 3/4 inches is how far out in front of the tip?
 
  #24  
Old 10-23-09, 12:10 PM
Member
Thread Starter
Join Date: Apr 2009
Location: New Hampshire
Posts: 13
Upvotes: 0
Received 0 Votes on 0 Posts
ecman,
I think you are referring to the turbulator at the end of the air tube. The static plate is located further down the air tube behind the nozzle and electrodes. I did find the dimension in my installation manual that Grady mentioned. I just don't know what the 2 3/4" means. Is it a dimension to something or the dimension of some part of the plate or something else?
 
  #25  
Old 10-23-09, 02:29 PM
Grady's Avatar
Forum Topic Moderator
Join Date: Jan 2005
Location: Delaware, The First State
Posts: 13,928
Upvotes: 0
Received 0 Votes on 0 Posts
Static Plate

The 2 3/4" is the diameter of the static plate. It should be stamped on the upstream side at the bottom.
 
  #26  
Old 10-24-09, 06:20 AM
Member
Thread Starter
Join Date: Apr 2009
Location: New Hampshire
Posts: 13
Upvotes: 0
Received 0 Votes on 0 Posts
Yesterday I pulled the whole burner apart and reset everything to factory specs. Cleaned the firesides of the boiler. Quite a bit of soot. Don't know if that was from the recent no start issues and the resulting smoking or had built up over time. Thought the soot might have affected the draft. Verified that atomized oil was coming out of the nozzle and that the spark at the electrode tips was good even with the blower air affecting the arc. Started right up. However, two hours later the safety tripped again. I then pulled the transformer and benched tested it. I set it up with a spark gap and left it to run for a while. Periodically I readjusted the gap to see how far the arc would draw. Over time I found it to be less than 3/4", getting down to a little less than 1/2". So, I went out and bought an electronic ignitor. Burner has been cycling now for 16 hours without a failure. Keeping my fingers crossed but it looks like it might have been the transformer. I am surprised that the one installed last year by the burner tech would have "failed" so soon but that's what it looks like. If it runs without failure for the next few days I'll need to find a good service that can adjust the burner properly with the appropriate equipment. Thanks to everyone for the suggestions and tips. It gave me a way to rule out lots of possible causes.
 
  #27  
Old 10-24-09, 08:18 AM
Member
Join Date: Feb 2007
Location: Brantford Ontario Canada
Posts: 117
Upvotes: 0
Received 0 Votes on 0 Posts
Hopefully you found the problem. Make sure to post back and let us know.
 
  #28  
Old 10-24-09, 05:28 PM
Grady's Avatar
Forum Topic Moderator
Join Date: Jan 2005
Location: Delaware, The First State
Posts: 13,928
Upvotes: 0
Received 0 Votes on 0 Posts
Gas Gun

Originally Posted by ecman51` View Post
Is that perhaps the term for what diffuses the fire coming out of a gun, into the combustion pot? My single gun gas furnace at home has such a plate out in front of the burner. Maybe the 2 3/4 inches is how far out in front of the tip?
The only place I've seen a flame diffuser or spreader in a gas gun is on a mobile home furnace.
 
  #29  
Old 10-26-09, 04:52 PM
Member
Thread Starter
Join Date: Apr 2009
Location: New Hampshire
Posts: 13
Upvotes: 0
Received 0 Votes on 0 Posts
Well, I've now got reasonable confidence that the no flame problem has been solved. Since I installed the new igniter the burner has run for over three days without any failures. I did not suspect the transformer since it was only replaced last winter and I had verified a good spark at the tips of the electrodes. As far as the second try always working, I can only guess that the extra oil sprayed in the chamber might have produces a more volatile environment for the spark to ignite the oil. In any case thanks to everyone who responded with suggestions to help narrow down the problem. Now I've got to get it tuned for efficiency.
 
  #30  
Old 10-26-09, 05:08 PM
Banned. Rule And/Or Policy Violation
Join Date: May 2007
Location: Wisconsin
Posts: 8,629
Upvotes: 0
Received 0 Votes on 0 Posts
Originally Posted by Grady View Post
The only place I've seen a flame diffuser or spreader in a gas gun is on a mobile home furnace.
The 4-plex I work on, has them also.
 
Reply

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


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