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Sequence of operation
Snow melting overview
A snow melting system can offer a safe,
convenient and cost-effective way to
remove snow and ice from surfaces.
Activating the snow melting system as
soon as the snow falls rather than waiting
for mechanical snow removal after snow
has accumulated is a safer alternative.
This eliminates slip hazards and reduces
the risk of injury by mechanized snow
melting equipment, thereby reducing
potential liability costs. Eliminating snow
plow equipment and corrosive salts also
reduces damage to the slab surface and to
the environment. Additionally, snow melting
systems, when controlled correctly, can be
cost competitive compared to mechanical
snow removal.
The snow melting control can operate in
one of three different ways:
•
Melt:
Heats the slab to melt snow or ice
•
Idle:
Pre-heats the slab just below freezing
to shorten the time required to melt snow
•
Off:
Snow melting system is off
The control display shows the control
operation in the home screen.
Slab temperature control
Controlling the slab temperature is critical
to minimizing the cost of snow melting. This
requires installation of the Pavement Snow
and Ice Sensor (A3040090) or Slab Sensor
for Aerial Snow Sensor (A3040073).
The sensor contains a built-in slab
temperature sensor. While the control
will continue to operate without a slab
sensor installed, operating costs will
be much higher.
The slab is operated using slab outdoor
reset. As the outdoor temperature gets
colder, the heat loss of the slab increases.
In order to keep the slab surface at a
constant temperature while operating, the
inner core of the slab must be heated above
the melt or idle temperature setting.
The amount that the slab inner core
temperature is above the melt or idle setting
is proportional to the outdoor temperature.
Since the slab sensor is installed below the
surface of the slab, it is not measuring the
true slab surface temperature, but rather the
inner core temperature.
The control automatically compensates for
this temperature difference. However, the
slab item in the View menu displays the
actual measured temperature, so it
is normal to view slab temperatures that
exceed the melt or idle temperature settings.
Melt operation
The snow melting system operates the
heating equipment to heat the slab from
a cold start or from the idle temperature
to reach the melt temperature setting to
melt snow or ice.
Melt operation can be triggered automatically
using the Pavement Snow and Ice Sensor,
the Aerial Snow Sensor or manually by
pressing a button. The melt temperature
setting affects calculated targets such as
the slab target and boiler target.
Surface temp. = 35˚F (1.7˚C)
Slab outdoor reset
Core (sensor) is warmer.
Decreasing air temperature
Slab surface temperature is constant.
Increasing slab core temperature