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OTHER VERSIONS
The following versions all incorporate energy efficiency features that make a valuable contribution to
enabling compliance with the European Energy Performance of Buildings Directive and the 2006
amendments to Part L of the UK Building Regulations.
Heat pump version (HP)
Heat pump versions are provided with a 4-way reversing valve and can produce hot water up to 45-50°C.
They are always supplied with a second thermostatic valve and a liquid receiver to optimise the efficiency of
the refrigerant cycle in heating and in cooling. The microprocessor is set for automatic defrost (for operation
in severe ambient conditions) and for Heat/Cool change over by digital input.
Free cooling version (FC)
The Free Cooling option is a system designed to give important energy savings, when the cooling system is
operating continuously and when ambients are low. Free cooling units use low temperature ambient air to
cool down the water in the system. In some situations, chilled water can be produced without any
mechanical refrigeration (compressors) with consequent large reduction of power consumption. The Free
Cooling system comprises:
Free cooling coil: Heat exchanger made of copper tubes and aluminium fins, with bleed
valves.
Microprocessor control: The “heart” of the system; it allows correct control of all parameters, leading
to high efficiencies over a range of ambient conditions.
3 way valve: An ON/OFF 3 way valve that opens/closes the free cooling circuit,
depending on the signal coming from the microprocessor control.
Head pressure control: Maintains the correct condensing pressure in the refrigerant circuit when
ambient temperatures are low. In Free Cooling systems, this effect is
achieved by partially closing refrigerant circuits in the condensing coil with
solenoid valves: this reduces the heat transfer capacity and maintains a
suitable condensing pressure.
Heat Recovery Version
A version that includes heat recovery by the addition of a de-superheater heat exchanger located between
the compressor and condenser, is also available. This de-superheater can be fitted to both chiller and heat
pump versions, however, in the heat pump it must be used only when in cooling mode. In heating mode the
water circuit must be isolated. The de-superheater is capable of generating 50°C hot water for domestic use
(washing etc) and can recover up to 25% of the energy removed in cooling by this manner. Such units make
a valuable contribution to energy efficiency.