Duct static pressure reset
A supervisory sequence for one air handler. It lowers the supply duct static pressure setpoint while the zones it serves are satisfied, and raises it when they report starved airflow. A lower static pressure lets the supply fan slow down; BOPTEST’s own controls hold every floor at a constant 400 Pa.
Written in our own words from the behavior of the Modelica Buildings Library’s generic trim and respond block as its multizone air handler supply fan sequence uses it. The parameter values are our choices for BOPTEST. It runs once per floor, fed by that floor’s five zone request sequences.
Interface
Section titled “Interface”| Point | Type | Meaning |
|---|---|---|
nReqPre |
integer input | Static pressure reset requests from the zones on this air handler |
u1FanOn |
boolean input | The supply fan is running |
dpSet |
real output, Pa | Duct static pressure setpoint |
Behavior in brief
Section titled “Behavior in brief”- Fan off:
dpSet= 400 Pa, at once. - Start delay: after the fan starts, 400 Pa for 600 s plus one 120 s update period.
- Updates on a 120 s grid: trim by −12 Pa, or, when requests exceed 2, respond by +15 Pa per extra request (capped at +32 Pa). The setpoint stays within [50, 400] Pa.
- A stopped fan resets the stored setpoint.
Validation
Section titled “Validation”- 6 scenarios from the independent reference model: start delay and trim down to the floor, ignore/respond/cap, the ceiling, saturation and release, request changes between updates, a fan stop and restart.
- A 20-block hand-built graph passes all 6; 11 deliberate mistakes each fail at least one.
How it did
Section titled “How it did”- Muse Spark: 3 of 3 first try (high effort, with the loop rule in the prompt).
- On BOPTEST with zone requests v2 and the plant reset, 10 hours: energy −24.1 %, thermal discomfort −42.1 %, CO2 discomfort +17.4 %, on one window it was tuned on. See Runtime results.
Full spec: specs/ahu_static_pressure_reset/spec.md