Introduction; Air Handler Interface Display Assembly; 24Vac Fuse - Trane ACONT900AC43UA Service Manual

Air Handler

Introduction

Air Handler Interface Display Assembly

The indoor user Interface Display Assembly will display:
• The Unit Model & Serial Number (Normal Display)
• System Status - Mode of Operation; Heating,
Cooling, Fan or OFF.
• Requested Airflow (CFM) when the thermostat is
calling
• Blower RPM
• Indoor Unit's Alert Codes
• Unit Test Cycle
• Blower Motor Speed (RPM) when operating
• Last Four Alerts
• Replacement Part List
• Personality Module Serial Number
• Stand alone operation, with a 24 Volt thermostat
• Exit

24VAC Fuse

The on-board 24VAC automotive type fuse is in series
with the 24 Volt A.C. terminal R. The fuse will protect
against short circuit conditions external to the control.
If the fuse opens, the control remains powered and will
turn on its Fault LED. If the system is running, it will
shut down all operation.
AH - A 2
An air handler's auxiliary heat will turn off at once.
There will be a several second delay before the indoor
blower is shut down. The User Interface Assembly will
display CHECK FUSE under indoor alerts.
The air handler can operate using the Communicating
System or with 24VAC thermostat inputs. The air
handler control will default to the communicating
system operation on initial power-up, and will ignore
any 24VAC input signals while in that state. The control
mode can be changed to 24VAC at the User Interface.
The control will operate the indoor blower motor and
electric heat contactors.