Standard equipment - Casing made of galvanised steel metal with polyester paint, white colour RAL 7035. Thermal insulation 10 mm thick, fire classification M1. - Self-supporting frame and access panels to the electric panel, compressors, fans, etc. Outdoor circuit - Axial 2-speed fans directly coupled to the motor. Watertight motor class F, IP54 and internal thermal protection. Dynamically balanced propellers and outdoor protective grille. - Coil with copper pipes and aluminium fins. Indoor circuit - Centrifugal fans coupling by pulleys and belts. Two double-intake turbines, with an impeller with front-curved blades. Greased spherical bearings, with no maintenance required. Two electric motors with tensioner, class F, IP55 and internal thermal protection. - Reusable air filters, assembled on a frame. - Coil with copper pipes and aluminium fins. - Condensates drain pan in galvanised steel. Cooling circuit - Hermetic scroll-type compressor with sound insulation, assembled on antivibration mounts. Control of phase equilibrium and the direction of rotation. - Crankcase heater (heat pump units). - Four-way cycle reversing valves (heat pump units). - Anti-acid dehydrator filters. - Thermostatic expansion valves with external equalisation. Gas burner - Natural gas or propane gas burner designed in accordance with the standards in force in compliance with the Gas Directive 90/396 EEC. - Output control with proportional actuator 0-10V performed by the burner’s own control. - Condensation boiler with premixing and modulation technology that allows performance close to 105% with regard to the lower heating value (LHV). - Combustion chamber in stainless steel AISI 430 and pipes for the hot gas exchanger and the smoke outlet manifold in stainless steel with a low carbon AISI 304L content to guarantee a high resistance to condensation. - The recovery pipes have a flat design and grooves to increase turbulence thus increasing the heat transfer coefficient and therefore reducing the fuel consumption. Protections - High and low pressure pressostats. - Compressor discharge temperature control. - Non-return valve built into the compressor. - Klixon in the compressor. - Differential pressostat for control of air flow. - Main door switch. - Magnetothermic protection switches for the compressor power line and fan motor. - Automatic switch in the control circuit.