The DRX series units, with single direct expansion cooling circuit, use air for cooling in the condensing stage, and are therefore combined with the DROU air-cooled outdoor condensing units.
Refrigerant circuit – DRX
Unit featuring a refrigerant circuit complete with the following components:
– direct expansion coil
– low pressure switch
– electronic expansion valve
– pressure transducer and temperature probe for electronic valve
– shut-off valves for connection to outdoor unit
– connections available from top or bottom
DROU
Unit supplied pre-charged with refrigerant and factory tested. Unit featuring a refrigerant circuit complete with the following components:
– filter-drier
– liquid indicator
– safety pressure switch to control high discharge pressure (manual reset)
– liquid receiver
– external connections with valves
The Row-DENCO air-conditioning unit is an innovative and efficient system for managing hot spots in data centers, guaranteeing low energy consumption and possibility to be used with HIGH DENSITY racks that generate extremely high loads, up to and over 40 kW/m² per rack. The use of the latest generation EC fans with brushless motors ensures excellent performance in terms of low power consumption and low noise. N+1 dynamic management of the EC fans to optimise consumption and cooling system redundancy are available as standard.
On the Row-DENCO versions, the units are positioned in rows of RACKS, with a layout so as to create cold aisles, where the cool air from the Rack Cooler is delivered, and hot aisles, where the air heated by the electronic equipment housed in the RACKS is discharged. These are individual units installed between the Racks in a row, so as to absorb the local heat load of the servers.
On Row-DENCO versions, the air to be cooled is taken in at the rear of the unit directly from the data center hot aisle (35 °C), giving considerable benefits in terms of both energy efficiency and cooling capacity, before being cooled and then delivered into the cold aisle (18-20 °C), in other words, at the front of the same rack where the air is taken in.
Row-DENCO indoor unit
Structure
Extremely compact structure that reduces overall dimensions, made from galvanised
steel plate with RAL9002 epoxy powder coating. The panelling is coated with an innovative double layer of plastic, is lined on the inside with special soundproofing material.
Fans
The use of latest generation 225 mm diameter radial fans with EC brushless motors
ensures excellent performance and low power consumption. N+1 dynamic management of EC fans is featured as standard, allowing operation at reduced flow-rate to optimise power consumption. Moreover, in the event of a fault on one fan, the other fans are operated at maximum speed to ensure the same cooling performance.
The fan section has been designed to allow rapid replacement in the event of faults,
thus reducing system downtime.
Filters
Regenerable polyester fibre filtering media (G2 efficiency) treated with synthetic resins, supported by a frame with protective metal mesh. The filtering media is flame retardant.
Air-Sources Heat Exchanger
Finned coil with large frontal surface area, made from mechanically expanded tubes and aluminium fins with hydrophilic treatment and high heat transfer area. The coil is placed upstream of the fans for optimum air distribution.
Electrical Panel
Built and wired in compliance with IEC 204-1/EN60204-1 standards, complete with fan contactor and overload protection.
Microprocessor Control System
The microprocessor, by managing the compressor for the direct expansion unit and the
modulating 3-way valve for the water chiller, controls cooling capacity and operating
alarms, with the possibility of connection to supervisory systems.
Outdoor condensing unit
For direct expansion versions, the DROU outdoor condensing unit combined with the
DRX indoor unit, is aircooled with axial-flow fans, fitted with INVERTER-DRIVEN HERMETIC SCROLL compressor for operation on R-410A refrigerant, mounted on rubber vibration dampers, complete with oil pre-charge, supplied with oil separator to ensure correct lubrication even at minimum speed, and fitted with thermal protector.
Structure
Powder coated metal plate base panelling and inside structure. Non-flammable closed cell polyethylene foam thermal insulation and soundproofing on the inside.
Inverter-Driven compressors
High efficiency hermetic scroll compressor with brushless DC motor, complete with
thermal protector, with electronic capacity control managed by INVERTER. This ensures unit operating efficiency even at part loads, which represent more than 75 % of normal operating time, meaning effective overall average energy savings of up to 50 % compared to traditional ON/OFF technology. Mounted on rubber vibration dampers, complete with sump heater, oil charge and oil separator to prevent migration of the gas charge and ensure lubrication of the compressor sump during operation at minimum speed. Complete with thermal protector and sump heater installed as standard on all versions.
Electrical panel
Power and control electrical panel constructed in accordance with IEC 204-1/
EN60204-1, complete with control and terminal blocks for connection to the power supply and auxiliary controls.