Install Instructions
Table Of Contents
- Contents
- Section 1: About the controllers
- Section 2: Installing the controllers
- Section 3: Changing the room setpoint
- Section 4: Configuring the controllers
- Section 5: Balancing airflow
- Section 6: Application drawings
- Section 7: Sequences of operation
- Section 8: System integration and networking
- Appendix A: K-factors
- Index
Illustration 7–5 Time proportional reheat operation
Room temp increase
HTG SP-2F
HTG SPAN
loop %
0
100
10
HTG %
Reheat
Floating reheat
If the controller is configured for floating reheat, it controls two binary triac outputs to drive
the inputs of a tri-state actuator connected to a valve. If the Reheat loop is less than 30%, the
valve is driven closed. If the loop is greater than 70%, the valve is driven open. If the loop is in
between 30% and 70%, no valve action is taken.
See the topic Floating reheat on page 49 for an application drawing.
Illustration 7–6 Floating reheat operation
HTG %
DRIVE
OPEN
DRIVE
CLOSED
loop %
0
100
70
Reheat
30
HTG SP
HTG SPAN
-2F
Room temp increase
NO ACTION
Balancing airflow sequence
Balancing airflow is the process of calibrating the internal airflow sensor to a known
standard. In the field, airflow is measured with an airflow hood or other measuring
instrument and then compared to the airflow measurements from the sensor in the
controller. The balancing process uses an STE-8001 or STE-8201 as the technicians setup
tool for initiating the balancing sequence and entering actual flow measurements.
When the balancing sequence starts, all other functions of the controller are locked out.
SimplyVAV Section 7: Sequences of operation
Revision G 61