The Small Y (PUMY) series is designed to achieve excellent energy efficiency values in both summer (EER) and winter (COP) operation. The entire range enjoys COP values close to 4, allowing them to be used even in regions where current regulations impose more restrictive performance limits.

The new Small Y (PUMY) is able to ensure heating mode operation in an even wider temperature range today ( -20°C to +15°C).

The design of the Small Y (PUMY) series allows the use of a direct expansion coil increased in both exchange surface area and density; the simultaneous adoption of the Heat Inter Charger subcooling circuit, a technology first introduced in units of this series, ensures high performance and high energy efficiency in cooling.

Thanks to the use of the LEV KIT and the dedicated Branch Box (available in 3- and 5-connection versions), it is now possible to connect the entire range of indoor units of the residential and commercial series whose stylistic canons are perfectly matched in those contexts (residential facilities and hotels) where design and elegance are decisive elements in the choice of indoor units.

The Branch Boxes are designed to give the system the highest possible configuration flexibility. Thus, systems equipped entirely with CITY MULTI VRF units, systems consisting exclusively of Residential/Commercial Series indoor units, or mixed systems in which the two types of units coexist can be realized.

Small Y (PUMY) allows maximum installation flexibility due to increased piping geometric limits.

The compressor adopts a pre-heating AC system. The routine is performed by monitoring refrigerant temperature and compressor temperature. The AC-type control makes it possible to decrease the power consumption in stand-by phase, which benefits seasonal efficiency.

Decree 2037/2000/EC sanctioned the banning of HCFC(R22) refrigerants in virgin form as of 1/1/2010. So in the event of a failure or simple leakage of refrigerant from an R22 air conditioner, it will no longer be possible to replenish the charge. The simplest and most advantageous solution, especially in the case of medium-small systems, is the complete replacement of the air conditioner for the following reasons:

• New generation air conditioners with R410A are much more efficient and therefore have reduced electrical consumption;
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• They are quieter and provide better air filtration;
• Availing of tax deductions for the replacement of the winter air conditioning system, it is possible to minimize the payback time of the investment.

The critical factor in replacing an existing air conditioner using R22 fluid with a new one with R410A refrigerant fluid is the chlorine and mineral oil residues that remain in the piping where the R22-containing air conditioner was installed: these residues are highly detrimental to the new air conditioner to be installed and, without a thorough remediation operation, would cause the oil to deteriorate and/or the refrigerant circuit to clog, resulting in system malfunction. In addition, the diameters and thicknesses of the piping may not match the diameters of the new units. The Small Y (PUMY) series of outdoor units have Mitsubishi Electric Replace Technology which allows reuse of existing piping without reclaiming, even for diameters with different cross sections. Thanks to an exclusive HAB oil and special compressor friction reduction technology, it is possible for most of our air conditioners to reuse old piping, saving on installation time and costs, material, and with maximum environmental friendliness.

The fan has an improved design that allows for better air distribution, increasing efficiency.

The Small Y (PUMY) range in sizes 4.5-5-6 HP can be combined with the hydronic modules Ecodan® HYDROBOX and IDROTANK, making it possible to create mixed systems (DHW, radiant or air heating and air cooling). Connection to the hydronic modules Ecodan® HYDROBOX and IDROTANK enables the Small Y (PUMY) series to produce hot water up to 55 °C. Thanks to the Branch Box (with 3 or 5 connections), it is now possible to independently manage the two distribution systems (WATER and AIR) as well as the production of domestic hot water.

The fans are able to better cleave air and control wind disturbance by ensuring high head at low sound impact. In fact, they are able to ensure, at the same noise value, 10% more outdoor airflow than the previous version. Small Y (PUMY) can operate in "low noise" mode by lowering the sound level by 2 dB. By connecting an external timer or switch, this mode can be associated with a predefined time slot.