Daikin EWADC12C-XL [174/304] Unit mode selection

Functional Control ESIE10-01

2–26 Part 2 – Functional Description

2.2.2 Unit Mode Selection

The operating mode of the unit is determined by set points and inputs to the chiller. The Available

Modes Set Point determines what modes of operation can be used. This set point also determines

whether the unit is configured for glycol use. The Control Source Set Point determines where a

command to change modes will come from. A digital input switches between cool mode and ice mode

if they are available and the control source is set to 'local'. The BMS mode request switches between

cool mode and ice mode if they are both available and the control source is set to 'network'.

The Available Modes Set Point should only be changeable when the unit switch is off. This is to avoid

changing modes of operation inadvertently while the chiller is running.

Unit Mode is set according to the following table.

Note: An "x" indicates that the value is ignored.

Glycol

Configuration

If the Available Modes Set Point is set to an option ‘w/Glycol’, then glycol operation should be enabled

for the unit. Glycol operation should only be disabled when the Available Modes Set Point is set to

‘Cool’.

Control Source

Set Point

Mode Cool/Ice

Input

BMS Cool/Ice

Request

Available Modes

Set Point

Unit Mode

xxxCoolCool

x x x Cool w/Glycol Cool

Local Off x Cool/Ice w/Glycol Cool

Local On x Cool/Ice w/Glycol Ice

Network x Cool Cool/Ice w/Glycol Cool

Network x Ice Cool/Ice w/Glycol Ice

x x x Ice w/Glycol Ice