Condensing Units
CU/CFCU
Condensing Units
19
Installation & Maintenance Manual : 6259626 IM V1.6.0 04/16
Commissioning
GENERAL
The following commissioning information is based on a complete matched Airedale
system using R407C.
PRE-START CHECKS
Once the whole system has been installed it is most important that the following pre-start
checks are made:-
GENERAL
1
The unit condition is satisfactory.
2
All pipework is complete and insulated where necessary.
ELECTRICAL
1
All electrical connections (both mains and control) are properly terminated.
2
The power supply is of the correct voltage and frequency.
3
External fuses/circuit breakers are of the correct rating.
4
The units are properly earthed in accordance with current regulations.
5
All pipework is earth bonded as required.
6
Check that there is a supply to the crankcase heater (if fitted) and ensure this is
switched on for a minimum of 2 hours prior to the unit operation.
REFRIGERATION
1
The unit condition is satisfactory.
2
All pipework is complete and insulated where necessary.
3
All fans are able to rotate freely.
4
The system has been evacuated correctly.
5
Check the operation of the high and low pressure switch settings (if fitted). These
should be as follows:-
HIGH PRESSURE SWITCH - 27 Bar ( 400 psi ) - CUT OUT
LOW PRESSURE SWITCH - 0.5 Bar ( 7 psi ) - CUT OUT
2.5 Bar ( 37 psi ) - CUT IN
6
The low pressure switch is automatically reset. The high pressure switch must be
reset by either switching the unit off/on at the isolator, or de-energising the
compressor signal from the indoor unit.
FAN SPEED / HEAD
PRESSURE CONTROL
The head pressure control (if fitted), allows control to be achieved in ambients down
to -20°C.
CUS/CUHS 1 - 4
Head pressure can be controlled by setting the fan speed to the desired range and
operating in the Cut off mode, whereby the voltage output to the fan is varied between
0-100%.
To adjust the fan speed, turn the slot headed screw on the transducer to the
desired output.
DEFROST CONTROL
(CU.1-4)
Defrost is controlled by a factory set defrost timer via a coil temperature sensor.
