For those who live in cold-prone
parts of the country, few home appliances play as critical a role as the
furnace. A quality furnace can ensure optimal comfort inside of your home while
minimizing the amount of energy you consume in the process. Of course, even a
top quality furnace won't provide consistent results if you don't keep it
properly maintained.
Those who neglect regular furnace
servicing may find themselves dealing with a wide variety of issues, including
the problem known as puffback. If you would like to improve your knowledge of
frequently experienced furnace problems, keep reading. This article offers
three important things to know about furnace puffback.
1. Puffback Is an Uncontrolled Explosion
Puffbacks occur when excessive
amounts of fuel vapors accumulate inside of your furnace's burner chamber. When
the furnace ignites, these vapors explode. Fortunately, this explosion doesn't
have the force necessary to put you and your family at risk. Yet over time,
puffback can take a serious toll on your HVAC system.
Puffbacks pose the greatest threat
due to the excessive amounts of soot and smoke they produce. Over time, such
soot builds up on the inner surfaces of your furnace and heat exchanger, often
leading to problems such as corrosion and clogged burner nozzles. Worse still,
that soot and smoke often find its way into the air of your home.
The explosion that occurs with each
puffback often has enough force to jar loose the flue vent connector at the top
of your furnace. This connection ensures that combustion gases flow efficiently
into the heat exchanger. A disconnected flue connector allows soot and smoke to
blow right into your home, often leading to noticeable black streaks on walls
and ceilings.
2. Puffback Can Affect Both Oil and Gas Furnaces
Puffback can occur in both natural
gas and oil-burning furnaces. Either type of furnace may accumulate fuel vapors
in the combustion chamber if not properly maintained. That said, puffback poses
a much more common problem for oil furnaces. For one thing, oil furnaces have
greater maintenance needs.
In other words, a neglected oil furnace will accumulate the
kind of issues that lead to puffback at a much greater rate. Furthermore, oil
furnaces tend to experience more severe puffback. Heating oil dissipates at a
much slower rate than natural gas, thus allowing it to accumulate in greater
quantities.
3. Numerous Underlying Issues Can Lead to Puffback
Puffback may stem from a variety of
furnace problems, many of them related to poor maintenance. The most direct
mechanism for puffback involves leaks in or around the furnace's combustion
chamber. Such leaks allow fuel to trickle into the combustion chamber even when
the furnace is not running. As soon as the burner turns on, this fuel ignites.
Also, puffback may stem from clogs
in the exhaust flue or chimney. If exhaust gases cannot vacate the system
quickly enough, they will remain inside of the furnace. This scenario alters
the delicate pressure balance needed for proper combustion, changing the
air-fuel ratio and leading to puffback. Such pressure problems may also occur
as the result of damage to the heat exchanger.
Puffbacks frequently happen as the result of clogged
burners. When fuel cannot enter a furnace smoothly, misfires often ensure,
allowing unburned fuel to accumulate inside the combustion chamber. Finally,
puff backs may stem from excessively dirty ignition electrodes. A dirty
electrode may fail to generate the spark needed for combustion, instead of
allowing fuel to puddle up inside of the furnace.
Ultimately, puffback puts your HVAC
system at risk of serious problems, especially if you don't attend to it
quickly enough. For more information about what it takes to keep puffback from
damaging your furnace, please contact
the HVAC experts
at A-1 Finchum Heating & Cooling.
