GEA Aircooled Condensing Units - GEA Happel Belgium

Specification
GEA Aircooled Condensing Units
C-Range
Components are mounted on a rigid galvanised steel base and enclosed by plastic
coated metal side sections and top lid. The base has plastic coated steel channel
feet to assist in transporting and sitting the unit. The feet have holes for securing the
unit in position when installed. The coil and fan(s) are mounted vertically so that air is
drawn through the coil and discharged horizontally through a plastic-coated wire fan
guard. The fan(s) and guard(s) are mounted on a galvanised steel diaphragm. The
compressor and electrical components are mounted in a sealed compartment at the
end of the unit.
Access to this compartment is by a removable panel fitted with a door interlocked
mains isolator. If required, additional access to this area and to the fan(s) can be
provided by removing the lid and side panels, which are held in place by self-tapping
screws.
The refrigerant pipe work between the compressor and condenser is fitted with a
vibration eliminating connector. The compressor suction pipe work is looped to
prevent vibration damage. Condenser liquid and compressor suction pipes terminate
as stub connections protruding through a recessed, galvanised service panel. The
compressor is protected by HP/LP switches, and condenser pressure is controlled by
a fan switch. HP/LP service tapings are on the compressor valves. The Condensing
Units are normally delivered with a 5 psig holding charge of nitrogen.
An electronic fan speed controller is fitted as standard and selects the optimum
condenser fan speed based upon the refrigerant condensing pressure as sensed by
a local transducer. Using this option ensures reliable expansion valve operation
under external winter ambient conditions as low as -30 °C.
The winter start kit is fitted as standard to allow positive refrigeration system start up
under low ambient conditions, this includes a timer to override the low pressure
switch for up to 5 minutes, until sufficient low side operating pressure is reached.
When used in conjunction with the GEA Denco C3-05 AH11 controller this function is
provided within the micro processor controls.
The compressor(s) are compliant scroll type running on R407C or R134a, are
complete with isolation valves, crankcase heater, and oil level sight glass. The
compressor is provided with an electrical contactor. For details of compressor sizes
fitted to each Condensing Unit, refer to the tables.
Condenser coils are constructed from three rows deep 3 / 8 " o/d copper inner grooved
tubes with aluminium fins spaced at 14 per inch.
The Condensing Units are normally wired for direct starting from the Air Handling
Unit's controls. A four (4) core 3 phase and neutral cable is required for the power
supply, which is normally supplied from the MCB’s within the Air Handling Unit. For
Standard (single compressor) units, a four (4) core cable is required between the Air
Handling Unit and Condensing Unit for control signal and alarms, whilst for V.R.F.
(twin compressor) units a seven (7) core cable is required. The HP/LP switches have
normally open contacts for use when alarm signals are required. These alarms are
connected into the microprocessor controls using the additional cores in the signal
cable.
Signal cables must be segregated from cables carrying mains potential. For long
cable runs provision must be made for voltage drop.
4 PR-2007-0346-GB • Subject to modifications • Status 05/2007