Daikin REYQ8-48PY1B, Service Manual

Page: 151 / 477

SiBE37-701_B Other Control
Function 140
5. Other Control
5.1 Backup Operation
If any of the compressors goes wrong, disable the relevant compressor or the relevant outdoor
unit from operating, and then conduct emergency operation only with operational compressors
or outdoor units.
"Emergency operation with remote controller reset" and "Emergency operation with outdoor unit
PCB setting" are available
(1) Emergency operation with remote controller reset
[Operating method]
Reset the remote controller. (Press the ON/OFF button for 4 seconds or more.)
[Details of operation]
Disable the defective outdoor unit from operating, and then only operate other outdoor
units.
(On systems with 1 outdoor unit, this emergency operation is not available.)
(2) Emergency operation with outdoor unit PCB setting
[Setting method]
Make setting of the compressor, "the operation of which is to be disabled", in field setting
mode (setting mode 2).
(For detail of the setting method, refer to page 231.)
[Details of operation]
Disable the compressor with "operation disable setting" made from operating and only
operate other compressors.
(On the system with 1 compressor "REYQ8PY1", this emergency operation is not
available.)
5.2 Demand Operation
In order to save the power consumption, the capacity of outdoor unit is saved with control
forcibly by using “Demand 1 Setting” or “Demand 2 Setting”.
To operate the unit with this mode, additional setting of “Continuous Demand Setting” or
external input by external control adaptor is required.
5.3 Heating Operation Prohibition
Heating operation is prohibited above 24°C outdoor air temperature.
Operating method
Applicable model
(1) Emergency operation with
remote controller reset
(Auto backup operation)
(2) Emergency operation with
outdoor unit PCB setting
(Manual backup operation)
REYQ8 ~ 16PY1 –
Backup operation by the
compressor
REYQ18 ~ 48PY1
Backup operation by the
outdoor unit
Backup operation by the
outdoor unit
Set item Condition Content
Demand 1 Mode 1 The compressor operates at approx. 60% or less of rating.
Mode 2 The compressor operates at approx. 70% or less of rating.
Mode 3 The compressor operates at approx. 80% or less of rating.
Demand 2

The compressor operates at approx. 40% or less of rating.