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EWWQ090G ÷ EWWQ720L - R410a - Water-cooled scroll chillers
EWLQ090G ÷ EWLQ720L - R410a - Condenser less
EWHQ100G ÷ EWHQ400G - R410a - Heat pump scroll chillers
Water cooled scroll chillers & heat pump
Operation
Manual
EWWQ - EWLQ - EWHQ
Water cooled scroll chiller &heat
pump
D-EOMWC01203-15EN
Operation Manual
39
The Return Reset may affect negatively the chiller operation when operated with
variable flow. Avoid to use this strategy in case of inverter water flow control.
5.2 Unit/Circuit Start-up
In this section, starting and stopping sequence of the unit will be described. All HMI status will be
briefly described to allow a better understanding of what is going on into the chiller control.
5.2.1 Prepare the unit to start
In order to let the unit start all the enable signals has to be changed to enable. The list of enabling
signals are:
Local/Remote Enable signals = Enable
Keypad Chiller Enable = Enable
BMS Chiller Enable Setpoint = Enable
These items will be now discussed. Each unit is equipped with a Local/Remote selector. It is
installed on the unit switchbox and can be positioned on three different positions: Local, Disable,
Remote as shown in the following picture:
0
0
SR
T
AS
LWT SP
LWT SP - MR
MR
Heat Pump Mode
SR
T
Evap
T
AS
LWT SP
LWT SP + MR
MR
Chiller Mode
Evap
T
Cond
T