Siemens 125-1957 - Manual (Page 42)

APOGEE Heat Pump Controller – Multi-Stage Owner's Manual
32 Siemens Building Technologies, Inc.
Ordering Replacement Parts
If a controller is not operating correctly, order a new controller. The product number for
ordering a replacement controller is the controller product number preceded by an "R". The
replacement product numbers for accessories are the same as new product numbers:
Unit Vent Controller – 0 to 10V Output 540-509
CE Compliant Unit Vent Controller – 0 to 10V Output 550-509
Preventive Maintenance
Most controller components are designed so that, under normal circumstances, they do not
require preventive maintenance. Periodic inspections, voltage checks, and point checks are
normally not required. The controller's rugged design makes most preventive maintenance
unnecessary. However, devices that are exposed to dusty or dirty environments may require
periodic cleaning to function properly.
Safety Features
The controller board stores the controller's address, applications and point values. In the
event of a power failure or a reset, these values are retrieved from the controller's permanent
memory and are used by the controller unless overridden by a field panel. If one of the
following conditions occurs, the controller will activate safety features present in its fail-safe
mode.
• Sensor
failure.
• Loss of power. Upon controller power loss, communication with the controller is also
lost. The controller will appear as failed ( *F* ) at the field panel.
Controller LEDs
To determine if the controller is powered up and working, verify that the Basic Sanity Test
(BST) Light Emitting Diode (LED) is flashing ON/OFF once per second. The controller
contains eleven LEDs located on the circuit board. See the Controller LED indicators section
of Chapter 1, Product Overview for more information about LEDs.
NOTE: The TX and RX LEDs indicate communication over the FLN.