Single-zone snow melt control installation and operation manual | 27
Away key
Disable the snow melting system with the
Away Key. To turn on the Away Key, go to
the Display menu.
• Select AWAY KEY.
• Select ON.
To activate the Away Override (once the
Away Key has been activated).
• Touch “Going Away” on the screen.
• Select PERM (permanent) or a number of
days using the or arrow. Range is 1
to 180 days.
• Press the home button to accept the
setting or leave the screen
untouched for several seconds.
• “Away” is displayed on the home screen
until the number of days expires.
• Touch “Cancel Away” to cancel at any time
Slab protection
In a hydronic snow melting system, the
boiler or heating plant capacity may be
much larger than the load of the snow
melting zones. This can result in large
temperature differentials between the
supply water temperature and the slab,
creating large tensile stresses on
the slab.
Concrete is weak to tensile forces and when
repeatedly exposed to tensile loads the
concrete may crack. This may be prevented
by selecting the Protect Slab setting in the
System menu to On. The control measures
and limits the temperature differential
between the supply water and the slab.
Application modes
The snow melting control can operate either
an electric or a hydronic snow melting
system. A hydronic system can be further
categorized as either boiler or pulse width
modulation (PWM) zone operation as well
as whether the boiler plant is dedicated or
non-dedicated for the snow melting system.
A dedicated boiler only provides heat from
the snow melting system. A non-dedicated
boiler provides heat for the snow melting
system in addition to the space heating and/
or domestic hot water system. The control
requires that one of the following Application
Modes is selected in the System menu:
• PWM: Pulse width modulation
• BOIL: Boiler operation
• ELEC: Electrical operation
Tensile stresses
