Mitsubishi Electric PLA-ZM Series



 Mitsubishi Electric PLA-ZM Series – Ceiling Cassette Air Conditioner Review

Overview

The Mitsubishi Electric PLA-ZM series represents the latest generation of ceiling cassette air conditioners designed for commercial environments such as offices, retail stores, and restaurants. With advanced inverter technology, uniform 4-way airflow, and a high energy rating, the PLA-ZM range remains one of the most efficient ceiling cassettes on the UK market.

Technical Performance

Each unit in the PLA-ZM lineup delivers cooling capacities from 3.5 kW to 14 kW and heating up to 16 kW, depending on configuration.
Energy performance ratings reach A++ for cooling and A+ for heating (tested to EN14825:2024).
Airflow distribution achieves 15 m horizontal throw in all four directions, ensuring consistent temperature without drafts — ideal for open-plan offices and meeting rooms.

 Inverter Technology and Compressor Design

The series uses Mitsubishi’s Poki-Pokii DC Scroll inverter compressor, which modulates output between 20 % and 120 % of nominal load. This adaptive control allows precise temperature regulation and up to 35 % energy savings compared to fixed-speed models.
The inverter PCB uses intelligent power factor correction for smoother current draw, reducing start-up current by 50 %.

 Low-Noise Operation

Sound levels are among the lowest in its class:

• Indoor unit: 28 – 36 dB(A) (depending on mode)

• Outdoor unit: 46 – 50 dB(A)

The improved cross-flow fan and insulated drain pan contribute to silent performance — crucial for workspaces or hospitality zones.

 Air Quality and Filtration

Each PLA-ZM unit is equipped with Nano-Platinum filters and an optional Plasma Quad+ module, removing 99 % of airborne particles down to PM 2.5.
An integrated “i-see” 3D sensor scans the room for occupancy and temperature distribution, automatically adjusting airflow direction and volume for maximum comfort.

 Control and Connectivity

The system integrates with Mitsubishi’s PAR-WT50R-E wired controller or optional Wi-Fi MELCloud module.
Users can monitor consumption data, temperature trends, and maintenance status via smartphone.
Compatibility with BMS protocols (Modbus/BACnet) enables seamless integration into building management systems.

 Installation and Maintenance

The cassette fits standard 600×600 mm ceiling grids, simplifying retrofit projects. Drain-pump lift height: 850 mm.
Service panels are fully removable for easy filter replacement and coil access.
Refrigerant line lengths: up to 75 m, vertical separation: 30 m, making the system flexible for multi-storey buildings.

 Verdict

The Mitsubishi Electric PLA-ZM series sets a benchmark for commercial comfort and energy efficiency in the UK. Its quiet performance, adaptive inverter, and intelligent controls make it ideal for London offices and retail environments seeking reliable year-round climate control.