Higher COPs for close-control air conditioning

More efficient close-control air-conditioning units from Mitsubishi Electric uses R410A.
Mitsubishi Electric has upgraded its PFD close-control air-conditioning system with the launch of R410A versions with a 20%-plus increase in COP. These inverter-driven units qualify for Enhanced Capital Allowances. Philip Ord, product marketing manager, explains, ‘On paper, the change in refrigerant takes the PFD units from a COP of 2.57 to 33.0. In reality, at temperatures of between 20 and 25°C they will deliver COPs of 3.83 to 4.14.’ PFD units can consistently control temperature to within 1 K and can achieve total ly sensible cooling of up, depending on conditions. Inverter drives reduce starting current to 10 A, compared with up to 100 A for other systems. The new models offer 28 or 56 kW of cooling and 31.5 or 63 W of heating. Pipe runs are increased to 150 m, and goose-neck oil traps are not required. Units can be fitted with a soft-start intelligent-inverter kit that can reduce starting current to 5 A for a 10 hp model and increase system efficiency by up to 8%.
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