Service manual

System control Si18-201
154 Main Functions
3.28.6 Control Based on Relative Flow Rate Instruction
Purpose of the
Function
This function operates the motorized valve based on the relative flow rate instruction sent from
the outdoor unit.
Outline This function distributes the relative flow rate instruction sent from the outdoor unit to each room
unit in connection, and obtain the amount of change in the target motorized valve flow rate.
"
Base on absolute flow rate QR sent from the outdoor unit, the corrected flow rate value for
each room unit is obtained with the following equation.
QRDA = QR × KSQA / (
Σ
KSQRU +
β
R ×
Σ
KSQRT)
QRDB and QRDC are obtained in the same way.
QRDA = QR × (
β
R × KSQRA) / (
Σ
KSQRU +
β
R ×
Σ
KSQRT)
In case of the room A unit does not operate, QRDA can be obtained with the following
equation.
QRDB and QRDC are also obtained in the same way.
"
The target flow rate of motorized value (QAMK) is corrected using this function.
Σ
QRA =
Σ
QRA + QRDA
Σ
QRB =
Σ
QRB + QRDA
Σ
QRC =
Σ
QRC + QRDA