Airedale Condensing Units (CU) 3kW - 80kW - Manual (Page 4)

CUS 15 - 60 / HCU 20 – 30D
Condensing Units
Chiller & Condensing Units
Installation & Maintenance:Part No: 6259592 IM 07\14
4
Description
INTRODUCTION The condensing units comprise a compact housing incorporating all the necessary
components and associated controls required.
The multiple condenser fan and motor assemblies provide an even airflow across the
condenser coils and then discharge vertically upwards. The condenser coils are in a
“V” formation on units in the range CUS 15 to 30D and in a twin vertical formation on
units in the range CUS 40 to 60D and HCU 20 to 30D.
COMPRESSORS CUS 15 - 30D AND HCU 20 - 30D
Three phase hermetic scroll compressors are used in this range of condensing units.
They are fitted with an internal thermal protector to protect the compressor from
damage against high motor winding and discharge gas temperatures.
CUS 40 - 60D
Three phase fully hermetic twin scroll compressors are used enabling each of the two
circuits to operate at 50% or 100% duty according to demand. Each twin compressor
is fitted with a thermistor protector module to protect the compressor from an overheat
condition.
REFRIGERATION Each circuit is fitted with a liquid line shut-off valve to allow for isolation of the
condensing unit during service or maintenance, and this is fitted with a schraeder
access connector to facilitate connection of a service gauge manifold.
The suction line connection is capped and sealed ready for customer connection.
A large capacity filter drier is supplied loose for on-site installation.
A manual high pressure and automatic low pressure cut-out switch is fitted on each
circuit for system safety.
All units are configured to operate without pump-down.
CONTROL PANEL
The control panel is equipped with the necessary MCB’s, contactors and other items
to provide fully automatic safe operation. It is divided into mains and control sections
thereby ensuring voltage integrity between mains (400/230V) and controls (24V).
OPTIONS 1. When specified, the condenser fan is electronically speed controlled to ensure
that a stable head pressure can be achieved during all seasons.
2. A weatherproof mains isolator can be fitted to ensure mains isolation of the
electrical panel during adjustment and maintenance.
3. A soft start option may be fitted to compressors on the CUS 15 to 25D range.
This consists of a resistor bank which is inserted in the compressor circuit for 0.3
of a second to reduce current inrush.
4. In atmospheres where high corrosion is anticipated phenolic coated aluminium
finned coils can be supplied.
5. A large open mesh coil protection guard can be supplied for sites where coil
damage might be a problem (HCU20-30D only).
6. Compressors can be supplied charged with Ester oil suitable for use with the
environmentally friendly refrigerant R407C.