What is infrared heating?
The ultimate source of radiated heat is the sun,
which generates vast amounts of infrared heat through
gas combustion. This infrared heat passes directly
through space, but it warms the surface of the earth
and is, in fact, the energy source that makes life
possible on earth. For example, on a sunny day in
winter we enjoy the sun’s warmth even though the air
temperature is low.
Gas fired infrared heaters are sometimes called
mini suns because they both rely on gas (either propane
or natural gas) combustion to generate heat. infrared
heat warms people and objects at floor level, not
the air in the room. This is a major advantage because
warmed air rises to the ceiling where it is not needed.
How are conduction and
convection heating different than infrared heating?
Heat can be transferred in one of three ways:
- By conduction through solid bodies, such as through
a windowpane in your heated house to the (cold)
outside. The rate of heat transfer by conduction
is proportional to the temperature difference and
the conductivity of the material used through which
it is transferring.
- Through convection by warming air and moving the
warmed air to a cooler area. For example, a natural
gas furnace produces hot air that is moved throughout
the building by air ducts.
- Through radiant heat transfer, which unlike the
other two methods requires no intermediate conductor
or convector. That’s because infrared energy, like
light, passes directly from the source to the receiver.
The rate of heat transfer depends on the emissivity
of the source, the absorptivity of the receiver,
the difference between their absolute temperatures,
raised to the fourth power, and the distance between
them.
How do infrared heaters work?
Most infrared heaters employ gas (propane or natural
gas) combustion to heat a steel tube (tube heater)
or ceramic surface (luminous heater), which subsequently
emits infrared heat. It’s important to note how much
infrared heat is emitted (infrared efficiency).
You should also be aware that an infrared burner
produces both infrared radiant heat (that is directed
at people and objects) and convection heat that rises
and is effectively lost.
Which technology is newest
– tube or luminous
(high intensity) heaters?
Infrared radiant tube heaters were introduced after luminous heaters,
but the best luminous heaters employ more advances
and offer significantly better efficiency, a key advantage
of InfraSave luminous heaters. It’s also important
to note that the best choice depends on the budget,
the application and the payback period (when fuel
savings have paid for the heating system).
Is infrared radiant heating safe?
While the sun is a terrific source of infrared heat,
it also delivers damaging UV rays, which leads some
people to falsely conclude that the same problem applies
to infrared heaters. The sun produces UV because
it is an extremely high temperature source; InfraSave
infrared heaters are a medium temperature energy
source – the ideal range for three reasons: it
is below the UV range, a greater portion of the heat
energy is converted into infrared heat, most materials
are highly receptive to medium wave infrared heat.
The latter is a key reason why InfraSave infrared
radiant heaters can heat, dry and cure faster and more economically
than competing systems.
How is infrared heating
used to warm spaces in a building?
Gas-fired infrared heaters are mounted overhead
to direct infrared energy to the floor and the objects,
including people, at the working level of the building.
The infrared energy is absorbed by the floor and
the objects at the floor level, all of which become
warm and, in turn, heat the air in the building. Moreover,
the floor and objects continue to release heat to
the air, even after cold air is introduced or the
infrared heaters are turned off. Convection heating,
in sharp contrast, has two major drawbacks: the loss
of heat during transmission; hot air rises to the
ceiling, where it is not needed.
How is the temperature
controlled in an infrared heating system?
A thermostat shuts off the infrared heaters when
the desired air temperature is reached.
Note: Turning down an infrared heater to
a lower firing rate is counter productive because
it reduces the emiting surface temperature. That,
in turn, reduces the infrared component and changes
the wave length of the infrared output.
Why are InfraSave infrared
radiant heaters more efficient than competing models?
Many North American manufacturers have attempted
to capture market share by designing and building
cheap, low efficiency infrared heaters. These heaters
may appear to have an attractive purchase price, but
they are far more costly in the long run because they
use more fuel and deliver less infrared heat (up
to 65% of the heat is convection heat that rises to
the ceiling and is wasted.) Worse still, cheap infrared
heaters produce marginal comfort levels that reduce
productivity.
What is the difference between
space heating and spot heating?
Space heating refers to the warming of a room or
building for comfort or to avoid freezing. Spot heating
refers to the warming of a specific area within a
much larger unheated structure, such as the spectator
stands in an ice arena, a shipper’s station in an
unheated warehouse, work stations in a courier depot
or a restaurant patio.
Technical
background
Spot or area heating is a method of providing comfort
to an individual or group of individuals without heating
the entire space or building to a comfortable air
temperature level. InfraSave luminous infrared heaters
are the only heaters which offer a practical, economical
solution to the problem of providing comfort in relatively
large unheated structures that are sparsely populated.
No other method of heat transfer can warm individuals
without wasting the majority of the heat to surrounding
air.
The design criterion for the application of InfraSave
infrared for spot heating is different than that
of space heating. In a space heating application,
a combination of direct radiation and air temperature
creates the needed comfort condition. In spot heating,
only the direct radiation comes in to play in determining
the comfort attained by the individuals in the heated
area.
To successfully design a spot or area heating system,
the designer must become familiar with the design
conditions in the area to be heated. The air velocity
in the area must be determined accurately. The surrounding
air temperature and the activity level of the individuals
in the area to be heated must also be determined.
Once the design conditions are established, the proper
size and model of the InfraSave luminous infrared radiant heater can
be selected to properly heat the individuals or area
in question.
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