Airedale DeltaChill FreeCool 110kW - 1080kW - Manual (Page 8)

DELTACHILL
™
Chillers
8
Chillers
Technical Manual : 7022932_V1.9_11/2013
General Description
Standard Features
Construction The base is fabricated from galvanised steel to ensure a rigid, durable,
weatherproof construction.
The superstructure is manufactured from galvanised sheet steel coated with epoxy
baked powder paint to provide a durable and weatherproof finish.
Standard unit colour is Light Grey (RAL 7035).
Compressors and evaporator are mounted on a rigid galvanised heavy-duty sub frame.
Fully weatherproofed electrical panels are situated at one end of the unit.
Evaporator Stainless steel high efficiency brazed plate heat exchanger(s) will allow optimum heat
transfer between media. Each heat exchanger is insulated with closed cell polyurethane
foam to Class 1 fire rating.
A pad heater is fitted to the single evaporator and will protect against freeze up in
ambient temperatures as low as -20°C.
Internal water pipework is trace heated.
Connections for External Trace Heating (230V/500W available).
Free Cooling Coil The DeltaChill Free Cool chiller has been designed to provide the cooling load required
whilst optimising energy efficiency at all times and as such will take advantage of free
cooling whenever available. If the free cooling available cannot satisfy the required full
cooling load, direct expansion cooling is used to supplement the output.
The Free cool coil is manufactured from copper tube and aluminium fins.
Free Cooling Operation In high ambients where free cooling is not available the fan speed modulates in the
conventional manner to maintain a constant head pressure. Free cooling is initiated
wherever the outdoor ambient is 1°C less than the return water temperature.
The condensing temperature is constantly monitored and intelligently kept within the
compressor envelope to allow the fans to run as fast as possible and therefore achieve
the most free-cooling without having a negative impact on compressor integrity.
In ambients where the free cooling coil is capable of satisfying the full cooling demand,
the condenser fans are modulated to provide the desired duty. The condenser fans are
capable of being modulated between 25-100% of airflow to maintain the supply
water temperature.
During periods where the condenser fan speed has been reduced to a minimum, the
supply water temperature will then be controlled by the 3 way valve.
Condenser Fan & Motor -
AC Axial fan assemblies with finger proof grille and incorporating external rotor ac motor
technology, capable of highly accurate discreet speed control, discharges air vertically.
The fans offer maximum performance while keeping sound levels to a minimum.
Lifting Eye Bolts Lifting eye bolts shall be fitted to the unit.