Burner Technology
Several patentable features have been included in the INOV8 Waste Oil
Burner design to deal with the carbon precipitation and gassing-off problems
as follows: 
- A recirculation system is provided to maintain high levels of heat
transfer (velocities over three feet per second) as the oil is heated
to prevent the occurrence of the nucleate boiling and graphite precipitation.
- The recirculation system has automatic venting allowing the released
gases to escape and to maintain steady oil flow to the nozzle.
- The recirculation system in combination with an automatic vapor eliminator
provides a unique feature in that the oil pump becomes self-priming.
In fact, the charged recirculation loop causes the burner pump to act
like a vacuum pump with very low-pressure capabilities. Most codes require
locating the furnace (unit heater) eight feet off the floor.
- With all competitive units, it is necessary to use either a remote
floor mounted pump or involve rigorous priming. The self-contained oil
pump on the burner housing is adequate for most applications.
- A filter is included in the recirculation loop immediately after the
heater circuitry to entrap any small particles before the oil enters
the passage leading to the nozzle. Competitive units do not have such
a practical method to filter all oil between the heating system and
the fine aperture oil nozzle. The general solution has been to sacrifice
good atomization by using a large aperture nozzle.
- The recirculation loop system pumps hot oil so that viscosity variations
are minimized to maintain uniform firing rates over wide oil conditions.
- The recirculation system uses a built-in relief valve of the pump
to a desirable advantage. The flow rate through the valve is ten times
greater than what is encountered in the firing rate of the burner making
pressure regulation much more manageable.
- A pneumatic/mechanical device moves a needle through the combustion
gun to the aperture of the oil nozzle. This needle will prevent nozzle
drip at shut down, will maintain an open orifice for consistent firing,
and will ignite immediately since oil does not drain out of the final
delivery circuit.
 The
fact that other manufacturers of waste oil furnaces use the less expensive
residential combustion controller is not justification for its use here,
particularly when personnel and/or property would be placed in peril. There
have been many cases where buildings have been destroyed by fire initiated
by explosions of waste oil furnaces. The design of this waste oil furnace
includes a number of innovative concepts directed specifically to safety
and reliability, and yet, this manufacturer is convinced that a more sophisticated
primary combustion control is absolutely necessary.
The INOV8 burner uses an industrial rated primary safety control at a
cost ten times greater than the aforementioned residential control. It
is an industrially rated control qualified to monitor combustion equipment
as large as 2.5 million BTUH. The primary safety control features the
following programmed sequence:
- An oil temperature interlock to prevent firing of cold oil.
- An air pressure interlock to prevent oil delivery without proof of
atomizing air.
- A 90 second purge to insure venting of explosive vapors prior to each
start sequence insures there is no residual fire before introducing
new oil
- Start mode consists of a ten second trial-for-ignition period.
- Automatic sequence from start-mode to run-mode upon flame detection.
- A three second timing to terminate oil delivery if a flame outage
occurs during run mode.
- One attempt to re-establish flame, but only then, after repeating
steps 1, 2, 3 and 4 above.
- If flame is not detected within the ten second trial-for-ignition
period, the unit reverts to a full safety shutdown wherein power is
terminated to the combustion motor (oil pump) and the oil heater. After
safety shutdown occurs as indicated by a red light, manual reset is
required.
- Termination of spark ignition after flame established to lengthen
the life of the ignition transformer and the electrodes.
The primary safety control uses an ultra-violet flame detector. The ultra-violet
detector is not sensitive to daylight or artificial light, as is the case
with the cadmium cell detector, previously mentioned. The ultra-violet sensor
will "see" and respond to the flicker of a match or candle at a distance
of four feet, but will not "see" a strong artificial light at any distance.
This feature alone will prevent dangerous situations from occurring. One
of the more appealing aspects of the burner is the serviceability. The heart
of the burner is the "Slide-Out Fire Control Module". It is designed for
ease of servicing and should it need replacing a new Module can be replaced
within five minutes. This Module includes all of the operating controls;
temperature sensors, electric pre-heater and the needle actuator, which
could be subject to field failure. Replacing of this unit would not require
highly qualified technicians.
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