Marine air conditioners 48V DC
Air conditioning from the onboard batteries
48V is the voltage chosen by those designing the boat to minimize the use of the generator. It is the typical architecture of large boats and electric or hybrid boats, often equipped with lithium storage systems, where onboard energy is a resource to manage, not just to produce.
Blue-Airco 48V DC marine air conditioners are self-contained, variable-speed units, designed to integrate with these system configurations. Powered directly by the battery bank, a properly sized installation can air-condition cabins and onboard spaces using stored energy while reducing reliance on the genset.
With equal power, the switch from 24V to 48V halves the absorbed current. This makes it possible to reduce cable sizes, limit line losses, and simplify system integration, especially when multiple units are installed on board.
Thanks to the BLDC compressor, which modulates power, and the ECO function, they offer high comfort, optimized consumption, and silent operation.
The 48V DC range belongs to the Evolution Line, the most advanced line of Blue-Airco variable speed air conditioners: high-performance compressor, optimized heat exchangers, and faster EEV control for up to 15% higher efficiency compared to the previous generation.
They are designed, produced, and tested in Italy.
48V DC air conditioners are ideal for…
Large boats, electric and hybrid boats, and projects built around a 48V system, often with lithium batteries.
They are the choice for those who start from energy management, with the goal of reducing — or eliminating, with a properly sized system — the use of the generator for onboard comfort and keeping currents low despite the installed power.
For smaller boats or with lower voltage systems, 12V systems (small boats) or 24V systems (medium and medium-large sizes) are indicated.
The advantages of 48V DC Blue-Airco marine air conditioners
Independence from the generator
Air conditioning is powered directly by the 48V battery bank, without conversion to alternating current. With a properly sized system, onboard comfort no longer depends on starting the generator: quiet nights at anchor, no noise and no vibration.
Reduced currents for the same power
At 48V, the 18,200 BTU/h unit draws 19.8 A, compared to 39.6 A for the corresponding 24V version. Half the current means lower gauge wiring, reduced line losses, and less demanding protections: an advantage that increases with the size of the boat and the number of installed units.
Compatibility with electric and hybrid systems
On boats equipped with a 48V battery bank, often based on lithium technology, the air conditioning is connected directly to the storage system, without external conversions.
Modulated consumption and ECO mode
Power follows the actual environmental demand. In ECO mode, consumption drops to about 190–200 W depending on the model: it is the mode designed for prolonged nighttime use, when it is important to make the battery energy last.
Soft start without current spikes
Inverter technology eliminates start-up peaks, an important requirement for managing storage systems and their BMS.
Evolution Line efficiency
High-performance compressor, optimized heat exchangers, and faster EEV control ensure up to 15% higher efficiency compared to the previous generation: every watt saved is additional autonomy.
Reliability in the marine environment
The titanium heat exchanger offers very high resistance to corrosion and erosion and contributes to the reliability of the unit under typical marine usage conditions.
Compact and versatile
The monoblock design, with an adjustable fan, facilitates onboard integration and simplifies installation compared to more complex systems.
Made in Italy
Design, production, and testing are managed in Italy, with great attention to construction quality and the needs of the marine environment.
Technical specifications
All 48V DC units share an architecture designed for continuous use in marine environments, even under severe conditions (seawater up to 45 °C for cooling and down to 4 °C for heating):
Supply voltage: 48V DC.
Variable speed inverter technology with BLDC compressor and fan.
Titanium heat exchanger/condenser practically immune to marine corrosion.
Electronic expansion valve (EEV) for precise regulation of refrigerant flow under all operating conditions.
Multifunction 2.4″ capacitive touch display included; 3.5″ display available as an option.
ECO mode with very low consumption.
Soft start with elimination of current peaks.
Advanced installer menu and USB port to simplify installation, maintenance, and diagnostics.
Evolution Line connectivity (coming soon): bidirectional MQTT interface and local web server via Wi-Fi to monitor and control temperature, setpoint, mode, fan speed, on/off status, and alarms directly from a browser, with no app or cloud required.
Available models
The 48V DC range includes two models, both in the Evolution line. All models operate at 48V DC.
| Model | Max cooling capacity | Max power absorbed | Max current | ECO mode | Weight |
|---|---|---|---|---|---|
| SDC10V48E | up to 10,700 BTU/h (3.1 kW) | 670 W | 14.0 A | 4,500 BTU/h · 200 W · 4.2 A | 23 kg (50.7 lb) |
| SDC18V48E | up to 18,200 BTU/h (5.3 kW) | 950 W | 19.8 A | 5,000 BTU/h · 190 W · 4.0 A | 28 kg (61.7 lb) |
All capacity, power, and current values reported in the table refer to cooling operation. The 48V DC units are currently available with R410A refrigerant. New versions specifically designed for R-454C refrigerant are under development and will be available soon. Both units are reversible and can also operate in heating mode via heat pump. The values shown refer to tests carried out in tropical conditions, with sea water at 32 °C. For the complete specifications of each model, download the relevant datasheet.
Materials to download
Let's design your system together
Our technical support is free: we help you with 48V sizing and integration with the battery bank.