Setpoints - Johnson Controls - 24-9890-1397 - T612DFH-4 - T612DFH-4+PIR - T612DFH-4 and T612DFH-4+PIR Thermostat Controllers with Fan Control and Occupancy Sensing Capability

T612DFH-4 and T612DFH-4+PIR Thermostat Controllers with Fan Control and Occupancy Sensing Capability Installation Guide

Product
Thermostats > Thermostat Controls > T612DFH-4 and T612DFH-4+PIR Thermostat Controllers with Fan Control and Occupancy Sensing Capability
Document type
Installation Guide
Document number
24-9890-1397
Document revision
B
Revision date
2021-01-07
Product status
Discontinued

The Standby setpoints are under the same limitations and restrictions as the Occupied and Unoccupied setpoints. Standby setpoints reside between the corresponding Occupied and Unoccupied setpoint values.

The installer must be certain that the difference between the Standby and Occupied values can be recovered within a timely fashion to ensure occupancy comfort. In addition, the difference between the two values must be large enough to warrant maximum energy savings.

Hotel and lodging applications can benefit from the addition of an entry door switch wired to one of the binary inputs of the thermostat controller. When a door contact is used and configured, the Standby timer and its configuration are no longer active or used. The occupancy toggle between Occupied and Standby is then dictated by both the door contact and the PIR sensing device used. If movements are detected by the PIR sensor and the door is closed, the room is considered occupied. The thermostat controller switches back to Standby mode only if the door switch toggles open/closed. Motion is ignored when the door switch indicates an open door.

PIR occupancy functionality is dictated by both the Standby timer and Unoccupied timer configuration value and movements present in the area.

Figure 1. Increasing Room Temperature Setpoints
Figure 2. Unoccupied Timer Set to 6 Hours and Standby Timer Set to 2 Hours