Tracer, Zn.520, Diagnostics – Trane LO User Manual
Page 79
UNT-IOM-6
79
Tracer
®
ZN.520
Table 30. Tracer
®
ZN.520 Diagnostics
Diagnostic
Fan
Other Outputs (Note 1)
Condensate overflow
Off
Valves Closed, Fresh air damper Closed, electric heat Off,
Baseboard heat Off
Low temperature detection
Off
Valves Open, Fresh air damper Closed, electric heat Off,
Baseboard heat Off
Low air flow - fan failure
Off
Valves Closed, Fresh air damper Closed, electric heat Off,
Baseboard heat Off
Space temperature failure
Off
Valves Closed, Fresh air damper Closed, electric heat Off,
Baseboard heat Off
Entering water temp failure
On
Valves Enabled (Note 2), Fresh air damper
Enabled (Note 2), electric heat Enabled (Note 2), Baseboard
heat Off
Discharge air temp low limit
Off
Valves Open, Fresh air damper Closed, electric heat Off,
Baseboard heat Off
Discharge air temp failure
Off
Valves Closed, Fresh air damper Closed, electric heat Off,
Baseboard heat Off,
Fresh air temp failure
On
Valves Enabled, Fresh air damper Minimum position
3
, electric
heat Enabled, Baseboard heat Enabled
Relative humidity failure
On
Valves Enabled, Fresh air damper Enabled, electric heat
Enabled, Baseboard heat Enabled
Generic 4-20ma failure
On
Valves Enabled, Fresh air damper Enabled, electric heat
Enabled, Baseboard heat Enabled
CO
2
Input failure
On
Valves Enabled, Fresh air damper Enabled, electric heat
Enabled, Baseboard heat Enabled
Maintenance required
On
Valves Enabled, Fresh air damper Enabled, electric heat
Enabled, Baseboard heat Enabled
Local fan mode failure
On
Valves Enabled, Fresh air damper Enabled, Electric Heat
Enabled, Baseboard heat Enabled
Local setpoint failure
On
Valves Enabled, Fresh air damper Enabled, electric heat
Enabled, Baseboard heat Enabled
Invalid unit configuration
Off
Valves Disabled, Fresh air damper Disabled, electric heat
Disabled, Baseboard heat Disabled
Normal power up
On Valves Enabled, Fresh air damper Enabled, Electric heat
Enabled
Note 1: The generic binary output (TB4-1, TB4-2) state is unaffected by all unit diagnostics.
Note 2: When the entering water temperature is required but not present, the Tracer
®
ZN.520 controller
generates a diagnostic to indicate the sensor loss condition. The controller automatically clears the
diagnostic once a valid entering water temperature value is present (non-latching diagnostic). When the
entering water temperature sensor fails, the controller prohibits all hydronic cooling operation, but allows
the delivery of heat when heating is required. In the Cool mode, all cooling is locked-out, but normal fan
and outdoor air damper operation is permitted.
Diagnostics