EWWQ090G ÷ EWWQ720L - R410A - Water-cooled scroll chillers
EWLQ090G ÷ EWLQ720L - R410A - Condenser less
EWHQ100G ÷ EWHQ400G - R410A - Heat pump scroll chillers
EWAQ-
- R410A - Air-cooled scroll chillers
EWAQ-
- R410A - Air-cooled scroll chillers
EWYQ-
- R410A - Air-cooled scroll heat pumps
Air and Water cooled scroll chillers & heat pump
Operation
Manual
EWWQ - EWLQ - EWHQ
EWAQ - EWYQ
Air or Water cooled scroll chiller &
heat pump
D-EOMHW00107-15EN
Operation Manual
49
MR
Max Reset
AS
Active Setpoint
LWT SP
LWT Target
MROAT-C
Max Reset OAT Cooling
SROAT-C
Start Reset OAT Cooling
MROAT-H
Max Reset OAT Heating
SROAT-H
Start Reset OAT Heating
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:
OAT
AS
LWT SP
LWT SP - MR
MR
Heat Mode
MROAT-C
OAT
AS
LWT SP
LWT SP + MR
MR
Cool Mode
SROAT-C
SROAT-H
MROAT-H