beckett/ruud intermittent puffback
#1
03-30-10, 02:15 PM
beckett/ruud intermittent puffback
Hello everyone, 1st time poster long time reader
I have a tough problem and would love some advice.
My furnace is a ruud achiever high efficiency forced hot air furnace. It has a beckett burner afg, with a .65 70degree b delevan nozzle. It has a new tank, single pipe off the bottom of the tank, which feeds into a spin on wix oil furnace filter.
The tank is inside. It heats a smaller 1960s trailer, which sits on its own foundation and has a 3/4 basement. There is a duct for each room but a return only in the bathroom and bedroom which are at the farthest end of the house away from the furnace. It also has one register in the basement and one return which was put right in the air handler filter inlet. Bad design thats for sure.
I have had a puffback problem since I bought the house five years ago with only 2 years on the furnace.
Its very intermittent and can go for months without any problems. What happens is when the furnace sits for a few hours, it will get a puffback of smoke out of the burner after the blower in the burner shuts down. It will leave a film of brown burned oil inside the burner and a small quarter sized puddle of burned fuel in the center of the burner tube. It may go three months without a problem, but it happens at least one or twice a year.
When it first had the puffback, I changed the nozzle and filter and cleaned out the heat exchanger and chimney pipe. The problem came back a few months later, with only about 200 gallons of heating oil through it. A suburban tech was called, they came out and changed nozzle and filter with the problem returning only a few days later. For some reason he changed the transformer and did some adjustments. The heating season ended right after that. Next year same off and on problem. I added a electric fuel shutoff valve and changed the pump. Problem returned a few months later. I spoke to the service guy who installed the furnace who thought it might be a draft problem and said to seal off the draft regulator. That didnt work either. Spoke to another tech and he said it could be a contamination problem with junk from the tank, which was in rough shape, so a new filter was set up after the felt strainer and I checked the screen in the pump which was clean as a whistle.I also installed a new tank. Again another puffback a few months into things and this time I called the installer to come out, after I had done a nozzle, filter, cleaning and check the burner with instruments and see if it was a draft problem. The air band was moved a teeny bit and he said the draft was fine. And soon after another puffback. So I figured id try a new burner tube assy with a delevan protec nozzle check valve. Worked fine all season untill yesterday with a puffback. Changed the nozzle and filter again, checked the heat exchanger which is a little sooty but just a little and the chimney and inlet are clear. I dont know what else to do. I blocked off the return that was close to the furnace and piped it 20 feet over to the other side of the basement thinking that the furnace was backdrafting from the return being so close to the burner but had no help. Any Ideas, suggestions? The lady of the house is fed up and with 2 kids here I understand her frustration.
I have a tough problem and would love some advice. My furnace is a ruud achiever high efficiency forced hot air furnace. It has a beckett burner afg, with a .65 70degree b delevan nozzle. It has a new tank, single pipe off the bottom of the tank, which feeds into a spin on wix oil furnace filter.
The tank is inside. It heats a smaller 1960s trailer, which sits on its own foundation and has a 3/4 basement. There is a duct for each room but a return only in the bathroom and bedroom which are at the farthest end of the house away from the furnace. It also has one register in the basement and one return which was put right in the air handler filter inlet. Bad design thats for sure.
I have had a puffback problem since I bought the house five years ago with only 2 years on the furnace.
Its very intermittent and can go for months without any problems. What happens is when the furnace sits for a few hours, it will get a puffback of smoke out of the burner after the blower in the burner shuts down. It will leave a film of brown burned oil inside the burner and a small quarter sized puddle of burned fuel in the center of the burner tube. It may go three months without a problem, but it happens at least one or twice a year.
When it first had the puffback, I changed the nozzle and filter and cleaned out the heat exchanger and chimney pipe. The problem came back a few months later, with only about 200 gallons of heating oil through it. A suburban tech was called, they came out and changed nozzle and filter with the problem returning only a few days later. For some reason he changed the transformer and did some adjustments. The heating season ended right after that. Next year same off and on problem. I added a electric fuel shutoff valve and changed the pump. Problem returned a few months later. I spoke to the service guy who installed the furnace who thought it might be a draft problem and said to seal off the draft regulator. That didnt work either. Spoke to another tech and he said it could be a contamination problem with junk from the tank, which was in rough shape, so a new filter was set up after the felt strainer and I checked the screen in the pump which was clean as a whistle.I also installed a new tank. Again another puffback a few months into things and this time I called the installer to come out, after I had done a nozzle, filter, cleaning and check the burner with instruments and see if it was a draft problem. The air band was moved a teeny bit and he said the draft was fine. And soon after another puffback. So I figured id try a new burner tube assy with a delevan protec nozzle check valve. Worked fine all season untill yesterday with a puffback. Changed the nozzle and filter again, checked the heat exchanger which is a little sooty but just a little and the chimney and inlet are clear. I dont know what else to do. I blocked off the return that was close to the furnace and piped it 20 feet over to the other side of the basement thinking that the furnace was backdrafting from the return being so close to the burner but had no help. Any Ideas, suggestions? The lady of the house is fed up and with 2 kids here I understand her frustration.
#2
03-30-10, 05:37 PM
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Join Date: Jan 2005
Location: Delaware, The First State
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Tough One
Problems like this can be really tough in person. On the web???
What the hey, we'll give it a shot.
I have to think at this stage of the game there is something different going on to cause this problem only intermittently.
Something I've found to often help in situations like this is an outside combustion air kit such as Field Controls' Furnace Boot.
Many houses (including basements) suffer from negative pressure. Bringing combustion air from the outdoors directly to the burner eliminates this problem. I also strongly encourage the use of a primary control with a post purge feature.
The usual cause for symptoms such as you describe is heat reflected back onto the burner causing the oil to expand & weep out of the nozzle. If I remember correctly, that furnace has the fan controled by time rather than temperature which, in my opinion is the WORST way to control a fan, especially on an oil burner.
What the hey, we'll give it a shot.
I have to think at this stage of the game there is something different going on to cause this problem only intermittently.
Something I've found to often help in situations like this is an outside combustion air kit such as Field Controls' Furnace Boot.
Many houses (including basements) suffer from negative pressure. Bringing combustion air from the outdoors directly to the burner eliminates this problem. I also strongly encourage the use of a primary control with a post purge feature.
The usual cause for symptoms such as you describe is heat reflected back onto the burner causing the oil to expand & weep out of the nozzle. If I remember correctly, that furnace has the fan controled by time rather than temperature which, in my opinion is the WORST way to control a fan, especially on an oil burner.
#3
04-29-10, 10:33 AM
as it turns out, you were right Grady, it turned out to be a negative pressure issue in my basement. I have left my window open in the basement and it has been fine since then. We have had a run of weather that was perfect conditions for it to puff back but it hasnt. Now I know why there was a big hole left unrepaired in the basement wall when I bought the houseThanks for your help Grady, gold star for you!!!Beer 4U2
Thanks for your help Grady, gold star for you!!!Beer 4U2
#4
04-29-10, 07:40 PM
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Join Date: Jan 2005
Location: Delaware, The First State
Posts: 12,667
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Got Lucky
Even the blind dog finds a bone now & then.
Here's some information on various Field combustion air products. FIELD CONTROLS, LLC - CONTRACTOR PRODUCTS Combustion Air Systems
By using something like the air boot or furnace boot you wouldn't have to leave the window open.
I've installed a bunch of them & have always had good results.
BTW, I am in no way affiliated with Field Contols. Just like to suggest a good product when I encounter one.
Here's some information on various Field combustion air products. FIELD CONTROLS, LLC - CONTRACTOR PRODUCTS Combustion Air Systems
By using something like the air boot or furnace boot you wouldn't have to leave the window open.
I've installed a bunch of them & have always had good results.
BTW, I am in no way affiliated with Field Contols. Just like to suggest a good product when I encounter one.
