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Discover some tips to help keep fuel-oil
tanks, boilers and furnaces properly
maintained to run at their optimum.
By Harvey Grodjesk
Using preventive chemical heating-product additives
during annual boiler and furnace tune-ups can ensure
that customers’ equipment performs efficiently
throughout the winter heating season. Additives also can
help equipment reach its full lifecycle expectancy.
In addition to ensuring proper operation, selling preventive
chemical heating-product additives can add more profitability
to a service call. If presented properly, customers will appreciate
the extra care a service technician takes by suggesting
these treatments be applied and explaining what they do.
While some service technicians may not be proponents of
periodic boiler-water treatments, all boiler manufacturers recommend
them. Depending upon the inherent water chemistry
of local water conditions, a boiler can seemingly operate
fine for 5–10 years without a water treatment, however operational
longevity may eventually suffer.
Most treatments provide multiple benefits, including:
- Removing sludge and rust scale;
- Inhibiting boiler and steam line corrosion;
- Preventing oxygen pitting;
- Inhibiting lime scale;
- Preventing surging and foaming; and
- Checking water chemistry with built-in color indicators.
color indicators manufacturers build into them, which are useful
for visual water-quality checks. After application, a pinkishpurple
water sample indicates a proper pH water chemistry of
approximately 8.2, which is neither too alkaline nor acidic.
Blue or bluish-green water indicates more water treatment is
needed. A complete flushing may be needed if subsequent applications
do not generate the proper water color.
Too much alkalinity can cause surging, scale buildup, or
eventually “caustic embrittlement,” a process that causes the
metal to crack. Too much acidity, on the other hand, leads to
In large commercial boilers, these ailments are averted
with daily checks typically performed by maintenance staffs
trained to use sophisticated test kits to determine the boiler
water’s total alkalinity, water hardness, total dissolved solids
and other common water chemistry conditions. Conversely,
the average residential-boiler service technician does not have
this training or available jobsite time to execute such tests.
Fortunately, a water treatment with diagnostic color characteristics
is more efficient, simple to use and cost-effective.
Therefore, a boiler-water treatment that reacts to operating
conditions for proper water diagnostics is critical. Some
treatments do not chemically react to changing conditions,
but only add a color to indicate that some treatment has
been added to the water. This is similar to automotive antifreeze.
A greenish water color in an automotive radiator
proves antifreeze is present, but it is difficult to determine if
there is enough.
Water treatments that minimize corrosion are more important
today because boiler walls are manufactured thinner
for increased heat transfer, and the recent influx of overseas
metal alloys are not always reliable. Corrosion and scale can
also create hot spots, percolating noise and active pitting sites
that could affect the system’s future integrity.
Another diagnostic sign is water discoloration, which
in hot-water boilers probably signifies layers of corrosion are
building up. Corrosion affects heat transfer and efficiency and
will eventually lead to premature failure.
One of the most frequently occurring steam-boiler problems
is surging or water hammering, which generates noise and vibrations,
the latter of which can eventually damage pipes.
Soot buildup in a boiler’s oil-fired or gas-fired chamber, typically
caused by inefficient combustion, is a major service
checklist item. Soot acts as an insulator, thus cutting heattransfer
efficiency. Just a 1/32-in. layer of soot, for example,
can cause a 1%–2% decrease in efficiency. As layers of soot
thicken, the boiler efficiency exponentially decreases.
A soot spray can be applied during annual checkups, as
it reaches remote areas easier than vacuum attachments. A
soot stick can be burned in the chamber for a longer-term
Minimizing fuel-oil tank problems
The most common problem fuel-oil-fired boilers and furnaces
experience is moisture in the oil tank and fuel line. Typically,
moisture can cause an ice blockage, flame failure, sputtering
flame and corrosion-caused leaks from oxidation. Other problems
that occur in fuel-oil-tank storage include sludge, varnish,
waxing, gelling and general oil degradation.
Therefore, the most effective way to prevent these issues
is a year-round preventive treatment with an antifreeze and
other additives that minimize these ailments by dissolving
sludge and removing moisture. A year-round treatment can
be applied every fall as part of an annual heating-system
checkup. Also, since summer effects can cause condensation
within the tank, a mid-year treatment can be sold to the customer
to apply themselves in the spring.
Year-round treatments are not curative, but they can prevent
problems from manifesting over the course of several
years. Once too much moisture or sludge accumulates, the
customer is looking at system downtime, several hours of repair
and the expense of curative chemicals. In severe cases,
the service technician may need to revert to dumping, cleaning
and refilling the tank, which will cost the customer hundreds
of dollars, especially considering the cost of a fuel-oil
refill. A year-round fuel-oil treatment, along with periodic filter
replacements, can also minimize blockages in the fuel line
to the burner.
Not unlike the gasoline-additive market for engines, all
year-round fuel-oil treatments are not based on the same
science, but some manufacturers make the same claims. For example,
some treatments are merely kerosene, which will not
dissolve sludge or remove moisture. Additives with aromatic
hydrocarbons, such as naphtha solvents, have a high enough
kauri-butanol value to dissolve sludge. Likewise, additives
such as glycol ethers serve the dual purpose of de-icing and
removing moisture. A manufacturer’s material safety data
sheets will help determine which products use the most effective
Another part of the annual fuel-oil system checklist
should be a test detecting excessive water accumulation.
Typically, service technicians use a paste that detects and
locates water in fuel-oil tanks. The reddish-brown paste is
applied to a dipstick that reacts in the presence of excessive
moisture by turning fluorescent yellow-green.
There are many moisture-detection products on the market,
but some methods are better than others. For example,
some products depend on a pH reading to detect moisture.
However, this method can produce false readings or no
readings at all in the presence of alcohol, which concentrates
Obviously an oil tank with no water is the goal in a
perfect world; however, managing water to lower levels
with chemical additives might offer the customer the
most service-call value vs. time-consuming heating outages
and fills. If the fuel-oil line pick-up is 4 in. above the
tank’s bottom, a good rule of thumb would be to maintain
moisture below 1.5 in., which can be determined with the
aforementioned dipstick method. A water absorber can also
help reduce excessive water to those manageable levels.
Excessive water can also develop microbial growth,
which can lead to sludge and blockages. Microbes cannot
exist in oil, but they can exist in water and use oil for
Most of the aforementioned prevention methods are
not a matter of life and death, but heating systems left
untreated over time prematurely fail or create catastrophic repairs
that could be easily avoided with annual treatments and
checkups. It is up to the service technician to suggest and use
preventive products. Homeowners will likely pay for the extra
service and appreciate the conscientiousness with loyalty every
Harvey Grodjesk is Vice President of Operations for the Stewart-
Hall product line of RectorSeal Corp. Grodjesk is a 37-year veteran
of the chemical heating-product industry. RectorSeal offers
a variety of products for fuel tanks and fuel lines, such as yearround
treatments, water-detection pastes, water and sludge dispersant,
and several products for boilers. For more information,