Airedale Condensing Units (CU) 3kW - 80kW - Manual (Page 25)

Condensing Units
CUS 15 - 60 / HCU 20 – 30D
Chillers & Condensing Units
Installation & Maintenance:Part No: 6259592 IM 07/14
25
Maintenance Requirements
SAFETY WARNING : Ensure that ALL power to the unit is switched OFF before carrying
out any servicing or maintenance task.
ACCESS CUS 15 - 30D
Access to the compressors is via removable covers at the control panel end of the
unit. The low covers allow access to the compressors whilst the upper doors allow
access to the control panel.
Access is gained to the fan(s) from the top of the unit.
CUS 40 - 60D
Access to the compressors is via removable covers at the opposite end to the control
panel. In both cases there are removable covers which can be lifted off or hinged back
depending upon their location.
SERVICE CHECKS -
THREE MONTHLY At every service visit the following checks should be carried out:-
FAN AND MOTOR
ASSEMBLY 1 Examine the fan and motor assemblies for lateral and end play in the
bearings.
2 Examine the electrical gland plate to ensure that no water is entering the
motor.
3 Examine the fan blades for damage and corrosion.
REFRIGERATION
CIRCUITS 1 Check the suction and discharge pressures using a service gauge manifold
and compare them with the commissioning sheet. If there is any significant
variation, then the fault should be found and corrected. Refer to the
troubleshooting section.
2 Check that the high and low pressure switches are cutting out the
compressors at the correct settings.
High pressure switch cut-out 27.6 bar
Low pressure switch cut-out 0.5 bar
Low pressure switch cut-in 2.5 bar
Low pressure switch differential 2.0 bar
Ensure that both switches stop the compressor.
3 Ensure the fan head pressure controller is controlling the head pressure at
the required setting as shown on the commissioning sheets.
The gauges can then removed from the system. Do not forget to replace the security
caps on the schraeder valves.
CONDENSER COIL Clean the condenser coil with a stiff bristled hand brush. If dirt has accumulated over a
long period, or tends to be greasy or sticky, then it may be necessary to use a water
hose or chemical pressure hose. Take care not to damage the fins and comb out if
they have become damaged in any way.
IMPORTANT:- DO NOT USE STEAM FOR CLEANING CONDENSER COILS OTHERWISE
DAMAGE OR DANGER MAY RESULT FROM EXCESSIVE INTERNAL PRESSURES.