Airedale TurboChill FreeCool 200kW - 1830kW - Manual (Page 19)

19 Chiller Technical Manual 7525355 V1.1.0_04_2013
Introduction
Chillers TurboChill™ Air Cooled and FreeCool
Condenser
Large surface area microchannel coil(s) (ideally positioned to optimise airflow and heat transfer) shall be manufactured
a “V-block” arrangement. This “V-block” arrangement has a lower airside pressure drop making the fans run more
efficiently. The coils have freeflowing liquid drains that enables us to reduce the amount of subcooling done in the coil,
leaving more area for heat eachange.
R134a Leak Detection System
A factory calibrated leak detection system shall be fitted as standard to units containing circuits carrying > 300kg / circuit
of refrigerant to comply with F-gas legislation, however the leak detection system can be supplied as an optional extra
with refrigerant charges <300kg.
A dedicated refrigerant sensor shall be fitted within each compressor enclosure and will raise an alarm on detection of
refrigerant gas.
Maintainable Dual Pressure Relief Valve
An auto resetting pressure relief valve assembly shall be provided per evaporator circuit, opening on pressure rise
above 10.3 barg. The dual shut-off valve assembly incorporates 2 pressure relief valves which can be individually
shut off via a 3 way valve. This allows the maintenance of individual pressure relief valves without any requirement for
refrigerant evacuation.
In accordance with EN13136:2001, pressure relief valves have been sized to ensure that in the event of fire they can
prevent excessive build-up of pressure within the evaporator. EN13136:2001 section 6.2.1 has been used to size valves
accordingly.
Fire is a hazard that these units have not been designed to operate under. However, the inclusion of various safety
devices ensures that any damage due to fire is limited via the release of pressure in the form of gas discharge.
If concerns of the ability of the pressure relief valve to discharge in the event of a fire >107°C exist, then it is the
responsibility of the end user to protect the pressure relief valve assembly from excessive external temperatures.
This must however allow the pressure relief valve to discharge effectively and not act as a ‘choke’ (offer any resistance)
when discharging.