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11
Table 4. Alert Codes
Error
Code
Message
Type
Condition and
Email Notification
Description
Thermostat Display
Text
System Action
Action to Clear /
Recovery Condition
551
Critical
Lost communication
Problem (Zoning
Control)
A pop-up display will
appear indicating
communication error.
Indoor temp is displayed
as “--” on the home
screen.
inside
0
1
When any zone sensor
loses communication
with the damper control
module, the entire
system will go into
central mode.
Once communication is
reestablished the device will return
to normal zone operations.
Any lost communication between
the zone sensor and damper
control module will result in the
applicable error code being
displayed 542, 543, 544 or 545 at
the thermostat.
Check wiring between damper
control module and the zone
sensor reporting error code 551.