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7
Thermostat Control
Thermostat sequence of operation is outside the scope of this
guide. However, the operation of the Pearl Economizer Controller
is directly tied to the thermostat's decision to enable Heating,
Cooling or Ventilation. These decisions are based on thermostat
configuration, user set points, operating schedules, Demand
Response signals, and Occupancy sensors which are all fully
supported by Pelican thermostats. Setup and management of the
thermostat and all economizer and ventilation functions are
provided through an integrated Web-App.
Economizer Control
The economizer sequence provides cool outside air to satisfy
room cooling demand either by itself or in combination with
mechanical cooling stages. The proprietary algorithm maximizes
the use of free cooling and minimizes the use of mechanical
cooling.
1.
Configurable limits – High Temperature Limit, Minimum
Temperature Differential, and Fixed Enthalpy Limit restrict the
economizer from operating when set.
a. High Temperature Limit – If set, the economizer will be
disabled if the outside temperature (
OAT
) exceeds this value.
If left unset, the system will automatically adjust the high limit
based on the room temperature.
b. Minimum Temperature Differential – The economizer will
only be enabled if the outside temperature (
OAT
) is at least
this many degrees below the room temperature. This
should be configured based on the location's climate zone.
The default is 2°F.
