A2L Sensor - Johnson Controls - LIT-12011950 - Building automation software - Smart Equipment Controller - 5.0

Smart Equipment Controls Sequence of Operation Technical Bulletin

Brand
Johnson Controls
Product name
Smart Equipment Controller
Document type
Technical Bulletin
Document number
LIT-12011950
Version
5.0
Revision date
2024-06-06
Product status
Active
Language
English

Setpoints and related data

The setpoints and related data include the following items:
  • A2L Leak Detector Alarm (A2LLeakAlarm)
  • A2L Leak Detector Alarm-Lockout (A2LLeakAlarm-LO)

Inputs

The input for the A2L Sensor is the RDS (Refrigerant Detection System) binary input.

Outputs

The outputs include the following items:
  • Supply Fan goes to a fixed speed of 50%
  • All heating and cooling outputs are turned off

Operation

When the RDS Sensor binary input (BI) reads 0VAC, it is considered an alarm condition. When the BI reads 24VAC, it is considered the normal condition.

When an alarm is detected, the unit shuts down any cooling and heating outputs. The supply fan also turns on at 50%, if it was not already on. Heating and cooling remains off and the supply fan remains on as long as the RDS sensor is in the alarm condition, plus an additional 5 minutes after the sensor returns to the normal condition. If the alarm happens three times within two hours, the unit performs a lockout and requires a reset (ResetLO) to go back to normal operation.