Delta T Alerts And Utility Saver Switches; Data Logs - Honeywell Prestige 2.0 THX9421 Manual

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THX9321 PRESTIGE 2.0 AND THX9421 PRESTIGE
This tells you if the system is performing above or below
expected standards which would normally go unnoticed,
and may cause unnecessary energy use. It can also detect
and warn about problems early, before heating or cooling
equipment fails.
There are three alerts each for the heating and cooling
system. They occur when:
• the system is not operating
NOTE: The thermostat displays an alert when the
system does not reach a Delta T of 5 F after
the thermostat calls for a reasonable period
of time.
• the system is operating below the minimum Delta T
limit
• the system is operating above the maximum Delta T
limit
Delta T Alerts are displayed for basic failures including no
heating or no cooling that may be related to bad igniter,
bad flame sensor, bad gas valve, bad draft motor, bad
blower, bad contactor, bad startup capacitor, dead
compressor, etc.
Delta T Alerts are also displayed for performance related
issues such as dirty air filter, blocked registers, loss of
refrigerant, dirty a-coil, frozen a-coil, cracked heat
exchanger, dirty burners, burners need adjustment, etc.
Alerts are displayed to the user on the home screen. See
Fig. 161 for an example.
Fig. 161.
When the user presses the alert for more information, the
Notification screen is displayed, prompting them to
perform some basic troubleshooting and, if the problem
persists, contact their dealer. See Fig. 162 as an example.
Fig. 162.
68-0311—07
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IAQ WITH EIM
Alerts are also recorded in the Alerts Log. See "Data Logs"
beginning on page 90.
Delta T Alerts and Utility Saver
Switches
For systems that might be interrupted by a utility saver
switch (conventional cooling and heat pumps in the heat
and cool mode), the thermostat will ask if a utility saver
switch is installed and provide an option to the user to turn
off diagnostics temporarily while power is interrupted by
the utility company. Diagnostics can be turned off for 1-14
days.

Data Logs

The Data Logs collect system information that can help
point a service technician in the right direction when
troubleshooting.
When accessing the Data Logs, the installer can turn off
each log, delete current log entries, and save Data Logs to
a memory stick via the USB port. See "Using the Data
Logs" beginning on page 93 and "To save a Data Log to a
memory stick" beginning on page 94 for more
information.
Data Logs include the Alerts Log, User Interactions Log,
and Performance Logs.
90
Fig. 163.
Fig. 164.