Dometic Elite Control Series, Installation And Operating Manual

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11
EN
Elite Control Operation
7 .1 .4 Reversing-Valve Operation (DX
Systems Only)
COOL mode or HEAT mode is determined by the
position of the reversing valve. The reversing valve is
programmed to automatically toggle in these situations:
• When the system is running and an opposite cycle is
needed to maintain the temperature, the reversing
valve will toggle to the opposite position to initiate
the opposite cycle and reduce the starting surge of
the compressor.
• When a cooling or heating cycle is initiated after the
system has been OFF for less than five minutes.
• When a cycle is interrupted by changing the display
mode to OFF or changing the set point from the
display panel.
To reduce reversing-valve noise, unnecessary valve
toggling is limited by default. Program the minimum
compressor staging delay (parameter P-3) to five
minutes or greater, to eliminate valve toggling. Refer to
“Programming the Control” on page 14.
I When the system is powered up, a power-on-reset
always initiates a valve toggle.
7 .1 .5 De-icing Cycle (DX Systems Only)
DX systems have a de-icing cycle option to prevent ice
buildup on the evaporator coil during extended periods
of cooling operation. Installation variables, such as
grille sizes, length of ducting, insulation, and ambient
temperatures, determine the runtime required to achieve
the set point.
Factors that substantially increase the runtime include
operating the system with hatches and doors open and
programming an unrealistic set point (e.g. 65 °F/18 °C).
Such situations can cause the evaporator to form ice on
warm humid days.
De-icing is accomplished by closely monitoring the room
air temperature in 10-minute intervals during a cooling
cycle. Depending on the parameter value and the change
in room temperature during these monitoring intervals,
the control performs various actions to prevent ice from
forming or to melt ice that has already formed. This is
accomplished by short compressor shutdown periods
combined with a one-speed increase in the fan speed,
and by periodic HEAT mode cycles with the fan turned off.
The de-icing cycle algorithm initiates periodic
compressor shutdowns every 10 minutes if the inside
temperature is at or below 69 °F (20 °C). The lower the
temperature, the longer the compressor shutdown will
last. In addition, the de-icing cycle algorithm will perform
brief reverse cycle runs (with the fan purposely turned
off) if the cooling cycle runs for 40 minutes without any
cooling progress or if the cooling cycle runs for more
than 60 minutes, regardless of cooling progress.
The parameter setting for the de-icing feature
depends on whether you are using the
optional inside air temperature sensor or the
display built-in temperature sensor. Installation of an
optional inside air temperature sensor (located in the
return air path) greatly increases the effectiveness of the
de-icing feature, and this option should be considered
whenever the display sensor cannot read the room
temperature accurately.
For additional details on parameter settings and
navigation options, refer to “Selecting a Parameter” on
page 16 and “Navigation Tree” on page 24.
7 .2 Choosing the Control Operation
The four Mode indicators represent the different modes
of the control: COOL, DEHUMIDIFICATION, HEAT, and
AUXILIARY HEAT. Refer to “Using the Control Display
Panel” on page 13.
8 Choosing the Control Operation
1. Press and release the Mode button to select a
mode. Refer to “Available Modes and Options for
Operation” on page 12.