VEC100 Generic Rooftop Unit (RTU) Controller - Verasys - LIT-12013648 - LC-SBH200-0 - Building automation software - Verasys System - 4.0

Verasys Alarms Summary Technical Bulletin

Brand
Verasys
Product name
Verasys System
Document type
Technical Bulletin
Document number
LIT-12013648
Version
4.0
Revision date
2021-04-01
Product status
Active
Language
English
Table 1. VEC100 Generic RTU Controller Critical alarms summary
Description Cause
Unit Locked Out Due to APS

This alarm indicates that the current fan status or the current value of the duct static pressure is not in line with the supply fan command.

If Air Proving Switch Setup is set to Fan Status Device, this alarm indicates that the fan status mismatches the fan command.

If Air Proving Switch Setup is set to Duct Static Pressure Sensor, this alarm indicates that the duct static pressure is less than the minimum required 0.05 in. W.C. to turn on the supply fan, or that the duct static pressure value is unreliable.

Unit Locked Out Due to High Duct P This alarm indicates that the current value of the duct static pressure is greater than the maximum allowed duct static pressure value.
Table 2. VEC100 Generic RTU Controller Service Priority alarms summary
Description Cause
Outdoor Air Temperature Sensor Failure This alarm indicates that the current OAT value is unreliable.
Return Air Temperature Sensor Failure This alarm indicates that the current RAT value is unreliable.
Supply Air Temperature Sensor Failure This alarm indicates that the current SAT value is unreliable.
Main Controller Calibration Error This alarm indicates that an error occurred during the calibration of the controller.
Unit Shutdown Due to Air Proving Switch This alarm indicates the air proof loss state. If Air Proving Switch Setup is set to Fan Status Device, this alarm indicates that the fan status mismatches the fan command. If Air Proving Switch Setup is set to Duct Static Pressure Sensor, this alarm indicates that the duct static pressure is less than the minimum required 0.05 in. W.C. to turn on the supply fan, or that the duct static pressure value is unreliable.
MAT Sensor Failure This alarm indicates that the current mixed air temperature value is unreliable.
Table 3. VEC100 Generic RTU Controller Service alarms summary
Description Cause
Duct Pressure Sensor Failure This alarm indicates that the current duct static air pressure value is unreliable when the supply fan operates at variable speed.
Not Economizing – No Supply Air Sensor This alarm indicates an SAT sensor fault that affects the economizer functionality. It indicates that the SAT value is unreliable, which disables economizer mode and causes the sequencer to operate in mechanical state.
Fan Runtime Alarm This totalization alarm indicates that the supply fan reaches the run hours that the user defines. It indicates the need for service activities.
SAT High Temp Alarm This alarm indicates that the SAT value is greater than the high limit that the user defines for the cooling state of the controller. It indicates ineffective cooling.
SAT Low Temp Alarm This alarm indicates that the SAT value is less than the low limit that the user defines for the heating state of the controller. It indicates ineffective heating.
Dirty Filter This alarm indicates that the dirt content on the filter reaches the maximum limit. It indicates the need for service activities, such as filter replacement.
Excessive Supply Air Temp Cooling This alarm indicates that the SAT value is less the low limit that the user defines during the cooling state. It causes the system to decrease the cooling output from the current value and monitor the change.
Excessive Supply Air Temp Heating This alarm indicates that the SAT value is greater than the high limit the user defines during heating state. It causes the system to decrease the heating output from the current value and monitor the change.