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GAS FIRED WATER HEATERS
MANUALS & PARTS GUIDES - HVAC
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NO HEAT - FURNACE
ODORS & SMELLS DIAGNOSIS & CURE
ODORS FROM HEATING SYSTEMS
OIL BURNER NOISE SMOKE ODORS
Reset Switch - Heater Primary Control
STACK RELAY SWITCHES
STAIN DIAGNOSIS on BUILDING INTERIORS
STEAM HEATING SYSTEMS
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Oil Burner Puffbacks: this article explains the cause, cure, and prevention of potentially dangerous and sooty oil fired heating equipment puffbacks that can occur at an oil fired boiler, furnace, or water heater. We explain why puffbacks can be dangerous, as well as expensive. We describe the warning signs that a puffback problem may be developing and we give advice on what to do to prevent puffbacks.
Green links show where you are. © Copyright 2013 InspectAPedia.com, All Rights Reserved. Author Daniel Friedman.
Oil Burner Furnace or Boiler Puffback Warning Signs
Guide to Preventing Oil Burner Puffbacks in buildings
BOILER OPERATING PROBLEMS discusses the signs of improper oil fired hot water at operation. Warm air furnaces are discussed at FURNACES, HEATING, and problems with loss of heat are discussed at NO HEAT - BOILER / FURNACE DIAGNOSIS.
Frequently Asked Questions (FAQs) about Oil Fired Heating Equipment Puffbacks
Question: Do "faulty boilers" cause puffbacks? Where do I look for puffback damage to the boiler itself?
Reply: Do faulty boilers cause puffbacks? No, oil burner problems, oil piping leaks, or chimney maintenance troubles are the root cause of puffbacks.
A competent onsite inspection by an expert usually finds additional clues that help accurately diagnose a problem with or cause of malfunction in a heating boiler. That said, here are some things to consider:
Your quotation from your insurance company stating that the puffback was caused by a "defective heating boiler" is confusing because it is not a precisely correct description of heating equipment puffback problems.
The explanation we offer of the mechanism of a puffback in oil fired heating equipment is more detailed than a typical insurance adjuster would offer even if s/he understood the cause of puffbacks, but our explanation is also the correct one.
Our photo (above left) shows soot fragments on top of a water heater that was installed close to an oil-fired heating boiler that was not operating properly - the same boiler whose soot was deposited on the garage ceiling and walls in our earlier photo just above. Failure to notice and do something about this sooty boiler operation is a failure to notice and correct a boiler operation or maintenance problem.
List of Common Causes of Oil Burner Puffbacks
The various possible underlying cause of excess oil that is ignited at the start of a heating boiler on cycle and that fuels the puffback, are listed in the article starting with "leaks at equipment oil supply piping" and include a variety of problems.
But nearly all of the problems that are at the root cause of a puffback are maintenance or installation errors or omissions, including:
are examples of conditions that lead to an oil burner puffback. Here are two more possible causes of oil burner puffbacks:
None of these are innate defects in the heating boiler itself. Rather they are defects in installation or maintenance. So I would not use the term "defective boiler" to explain a puffback. I'd use the terms "improper boiler operation" or "inadequate heating equipment maintenance".
I suspect that your insurance company either does not understand these facts, that their policy does not distinguish between improper or inadequate maintenance of the heating system and actual defective heating equipment, or that they are speaking a bit loosely (read carelessly) and are calling improper or inadequate maintenance (your responsibility) a "defective boiler".
My OPINION is that in general and quite often, a homeowners' insurance policy limits coverage where the root cause of a loss is improper or inadequate maintenance - those are exactly what I consider to be at the root of most oil burner puffback problems.
Where do I look for puffback damage to the boiler itself?
Unless a visual inspection of the exterior of your heating boiler (or water heater) shows obvious bulges or cracks or missing parts (for example a blown-off inspection port cover) I don't think a homeowner can safely and accurately assess the condition of the heating system after a puffback.
Your heating service technician would be expected to examine the combustion chamber and the accessible/visible boiler internal surfaces and components for physical damage as well as to accurately diagnose and fix maintenance problems that can cause puffbacks.
And you won't be able to see the "amount of unburned oil" that damaged the boiler or that caused a puffback because that oil is gone - consumed in the burning and explosion of the puffback. Furthermore, because of the physical shock to boiler components during a puffback explosion, I wouldn't assume that the post-puffback boiler would run exactly as it was running before that event. For example a puffback could loosen an oil line connection, resulting in a greater air or oil leak than was present before the event.
The closest we can come to guesstimating the history of a puffback would be to note reports of the history of boiler operation complaints (odors, noises, sooting), the frequency and extensiveness of prior heating equipment maintenance and/or service calls, and the date of the last service call before the puffback.
Finally, although it is much less likely, a boiler that had just been serviced, and serviced properly, could have still have a puffback if, for example, a contaminant in the fuel tank or fuel delivery led to a clogged burner nozzle.
Follow-Up remarks: Inherent Vices in Oil Burners that Contribute to Puffbacks?
An inherent vice in an oil burner or oil fired heater that might contribute to a puffback might be a boiler or boiler control design that made the unit difficult to properly clean and service or adjust, but I'm not aware of such.
Oil burner operation that leads to what I call "sloppy" oil burner shut down or start-up can lead to un-burnt heating oil in the combustion chamber, as we enumerated in the puffback article where I've included this discussion.
About including the oil burner or the whole heater in the insurance claim, I pose that you'd need an onsite expert who could explain and document damage to the equipment that occurred as a result of the puffback, as opposed to simply causing the puffback.
Wear and Tear on Oil Burners Contribute to Puffbacks?
"Wear and tear" contribution to an oil burner puffback sounds theoretically possible but is outside my experience. In my experience it's proper maintenance that is central to proper oil burner operation, combined with two additional factors:
Occupants or owners need to notice when the oil fired heating equipment is not working normally (smells, soot, odors, loss of heat), and then to ask for service and repair.
Service technicians need to notice conditions that are likely to presage or even explain a future puffback such as excessive sooting, chimney draft problems, even more subtle clues to draft problems such as a missing draft regulator, visible oil leaks, difficulty obtaining proper draft at the fire and in the breech, repeated service callbacks.
There is a problem facing the service technician: too often the tech might notice a clue that indicates a problem that needs investigation or repair, but the tech has been given a large number of service calls to make and is thus in too much of a rush to even bring it up with the homeowner, or equally common, the technician mentions the concern and the homeowner says "Stop trying to increase your bill, you are already charging me too much, just clean and tune the boiler.".
Oil Tank or Oil Piping Contribute to Oil Burner Puffbacks?