AIREDALE TurboChill TCC11R04G-01, Техническое руководство

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Introduction
Chillers TurboChill™ R1234ze Air Cooled and FreeCool
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Chiller Technical Manual 7752785 V1.12.0_10_2018
Condenser
Large surface area microchannel coil(s) (ideally positioned to optimise airflow and heat transfer) shall be manufactured
as 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 enable us to reduce the amount of subcooling done in the coil,
leaving more area for heat exchange.
R1234ze(E) Leak Detection System
A factory calibrated leak detection system shall be fitted as standard to units
A dedicated refrigerant sensor shall be fitted within each compressor enclosure and will raise an alarm on detection of
refrigerant gas.
Actuated Suction Ball Valve(s)
To protect the compressors against liquid migration, actuated suction line ball valves shall be fitted. This protects the
compressors when there is no cooling demand by keeping the refrigerant in the evaporator, even if water is still flowing
through the unit. This option also serves as a means of isolating the majority of the system refrigerant charge in the
evaporator, upon a leak being detected.
Refrigerant Isolation
To maintain the functionality of the refrigerant partial pump down and isolation strategy in the event of a power failure.
This 24V actuator will be connected to a single phase permanent supply so that in the event of a power failure the
evaporator is isolated.
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.
Rupture discs are also fitted on systems with a refrigerant circuit charge larger than 300kg in line with EN 378-
2:2008+A2:2012 clause 6.2.6.5.
In accordance with EN13136:2013, 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. EN13136:2013 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.
Ensure single phase power supply is connected permanently to ensure that the system will isolate
refrigerant and ventilate the compressor housing in the event of a leak being detected. A UPS
permanent supply is required.
CAUTION