AIREDALE CR12 - Operating Limits; Control Device Adjustment

Commissioning Checklist
Operating Limits
Standard Variable Speed Head Pressure Control
Minimum Ambient Air DB °C -20°C
Maximum Ambient Air DB °C +48
Optional On / O󰀨 Head Pressure Control
Minimum Ambient Air DB °C -0°C
Maximum Ambient Air DB °C +48
(1) For conditions outside those quoted, please contact Airedale.
(2) Low ambient kits are available for applications with ambient temperatures below those quoted, please contact Airedale.
Control Device Adjustment
Standard AC Type Fans
When the condenser is matched to an Airedale indoor unit, head pressure control is provided by the indoor unit.
Unmatched condensers are supplied with a head pressure control device which can be either:
1 Variable speed control (standard)
2 On/O󰀨 pressure switch (optional)
The control device is factory pre-set.
To check the setting connect a pressure gauge with scale reading up to at least 45bar to the pressure tapping located in
the outlet manifold of the condenser and watch the operation of the fan as the pressure changes. If the settings require
adjustment, follow the instructions set out below and check new settings as explained above.
SET POINT Potentiometer position (%)
% 20 30 40 50 60 70 80 90 100
Range 0 - 45 barg
barg 9 13.5 18 22.5 27 31.5 36 40.5 45
DIFF Potentiometer position (%)
% 5 10 15 20
Range 0 - 45 barg
barg 2.3 4.5 6.8 9.0
Variable Speed Control
The fan speed is controlled via alteration of the supply voltage which corresponds to a particular condensing pressure.
The output voltage from the controller varies between a maximum of 95% and a minimum of 40% of the mains voltage
(ie 220 Volts down to approximately 90 Volts on a 230 Volt supply) as the condensing pressure varies within a band of 5
Bar.
The control system is suitable for temperatures down to -20°C.
The pressure set point corresponding to the maximum output voltage can be adjusted by means of a potentiometer
internal to the case of the controller.
Factory setting: Set = 26 barg (58%) - Standard Thermostatic Expansion Valve
= 22 barg (49%) - Optional Electronic Expansion Valve
Di󰀨erential = 5 barg (11%)
To adjust the set points, nd the required setting below and adjust the relevant potentiometer:
Before carrying out any work, ensure that the isolator is switched o󰀨.
CAUTION
CR12 - CR165 50/60Hz CONDENSERS
30 Condenser Technical Manual 6666879 V2_02_2020
Technical