NIST APAR4 – Heating coil valve command is frequently fully open (Mode 1 – Heating)
Applicable Systems
NISTAPAR: APAR4
Primary: AHU, RTU, MUA, ERV
Objective/Method/Outcome
Objective: Indicates that the heating coil valve is frequently fully open while the unit is in Mode 1 (Heating). This rule is a warning and indicates that the system may be out of control. If APAR3 is active, this rule is suppressed.
Method: Check if the HCV is fully open for over 8 occupied hours per week while the unit is in Mode 1 (Heating) and if APAR3 is active.
Outcome: An insight is generated when the HCV is fully open for over 8 occupied hours per week while the unit is in Mode 1 (Heating).
The movement tolerance of the HCV. This is used to define when the valve is open – everything above the formula (100 – HCV Error Threshold) is considered saturated.
2 (%)
Acceptable Hours per Week
60
The amount of time that this error is allowable for the unit per week. Anything more than that time is considered a fault.