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Economizer
Economizer is used to reduce the energy consumed by the cooling systems, by using low external air
temperatures to assist in the chilling process. When outdoor temperatures are lower relative to indoor
(room) temperatures, the system utilizes the cool outdoor air as a free cooling source.
The outdoor temperature (Teconomizer) triggering the activation of the economizer, can be measured
by the temperature sensor connected to T1,0 terminals (technician parameter P08="05") or by setting
a temperature value manually through communication - AV#129 "TEconomizerEffective".
When getting the temperature through communication, terminals T1,0 can be used for any other
functionality like External sensor/Soft start in heat sensor/Deicing in cool/Door switch/Key tag.
Whenever there is demand for cooling and the outdoor temperature conditions allow the operation of
the economizer, it will operate together with the regular cooling system and will not replace it.
Economizer will start and run as long as both of the following conditions are satisfied:
Teconomizer temperature < Room temperature -
Cool differential band
2
Room Temperature > Set point temperature
Room Temperature < Set point temperature -
Cool differential band
2
1.
2.
Economizer will stop when the following condition is satisfied:
1.
Temperature
Set point
Cool differential band
ON
OFF
Economizer
Room Temp.
Room Temp.
Teconomizer
Indication for the Economizer operation:
When Economizer is active, the “Cool” symbol will appear (or flash when active)
on display and the “Fan” symbol will flash.
Economizer
active
