I.C.E. HTDM Food Process Unit User Manual

Page 32

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6. Low Limit. When a temperature below this set point is

detected, after a 3-minute internal time delay, the ICECON II
controller will de-energize J1-5 and J1-3 and lock out on
“Low Limit Error”.

Combustion Set Points

Located across the bottom of the main screen of the ICECON
application are the six combustion set points. Each point has
three parameters that describe each point. The “Fan” box contains
a number that controls the cycle time of the solid-state relay and

triac control signal. This number will determine the speed at
which the combustion fan will rotate when firing at the
corresponding firing point.

The fan rotation speed is indicated by the “RPM” box. This value
is read in from the tachometer sensor as the combustion points are
configured. This value is used by the software as a reference to
ensure that the correct fan speed is maintained. Once configured

the RPM values must maintain a 200-rpm separation between points
and increase as you move from left to right across the screen.

The “Valve” box contains the valve set points. This will
represent actual DC voltage being sent to the modulating gas
valve. These points must increase as you transition form left to
right across the main screen. The valve functioning range is 2 to
10 VDC.

Altering Combustion Set Points

Calibrating the Tachometer

Before altering any points the main firing valve should be
switched to the closed position. When adjusting combustion points
it is possible to override the internal stepping functions.

To begin setting up the combustion curve access the “Tools” pull
down menu and select the “System tune” function. This gives
direct access to the combustion curve set points. The first point
(low fire) is displayed. To override the system and force the
system to low fire press the “Send” button. The combustion fan
will adjust to the appropriate speed and the modulation gas valve
will track to the correct voltage. It is important to notice that

the valve voltage does not correspond to the voltage that was
displayed on the main screen, it is in fact double. This is just
how it is at this time so live with it. When the main screen is