Wall-Mounted Multi-Split Systems: Smart Climate for the Entire Apartment

Wall-Mounted Multi-Split Systems: Efficient Climate Control for Multi-Room Apartments and Homes

When it comes to air conditioning three, four, or five rooms simultaneously, property owners face a dilemma: cover the building facade with a "garland" of outdoor units or find a more elegant engineering solution. Wall-mounted multi-split systems are the answer to this challenge. This is a technological compromise that allows connecting from 2 to 5 indoor wall modules to one powerful outdoor unit, preserving the facade aesthetics and ensuring an individual microclimate in each zone.

What is a Wall-Mounted Multi-Split System and How Does It Work?

Unlike a classic split system (one outdoor unit — one indoor unit), a multi-split system represents a complex refrigerant distribution network. The heart of the system is a high-power outdoor inverter unit equipped with electronic expansion valves (EEV) for each connection port.

The key feature lies in the intelligent distribution of performance. If only one indoor unit is on, the system directs the entire flow of freon to it, running at minimum RPMs. If all units are on, the compressor accelerates, and the electronics dose the refrigerant proportionally to the requests of each room. This allows achieving high seasonal energy efficiency (SEER), often exceeding the indicators of individual split systems.

"Free Match" Architecture

Most modern systems presented at Eurosanteh (for example, from Haier, Gree, or Mitsubishi Electric) support "Free Match" technology. This means you are not obliged to buy a ready-made set. You select one outdoor unit of the required capacity (e.g., 8 kW) and complete it with indoor wall units of different capacities:

• For the bedroom (10-15 m²): Quiet low-power unit (7000 BTU).
• For the living room (25-30 m²): High-performance unit (12000 or 18000 BTU).
• For the study: Standard unit (9000 BTU).

This avoids overpaying for excess power where it is not needed.

Advantages and "Pitfalls": An Honest Expert View

Choosing between installing several separate air conditioners and one multi-split system is always a search for balance. Let's consider the "pros" and "cons" that salespeople often stay silent about.

Why Choose a Multi-Split System?

• Facade Aesthetics (Face Control): In many new residential complexes in Chisinau, strict rules apply: one apartment — one place for an air conditioner. A multi-split is often the only legal way to cool the entire apartment.
• Less Noise and Vibration: One large inverter compressor operating at medium speeds creates less acoustic noise and structural vibration transmitted to the walls than 3-4 separate outdoor units working in resonance.
• Single Service Point: The service engineer needs to service and clean only one outdoor unit, which simplifies annual maintenance.

Devil's Advocate: What You Need to Know Before Buying

We are obliged to warn you about technical risks:

• "All or Nothing" Principle: If the compressor or control board of the outdoor unit fails, all indoor units will stop working simultaneously. In the case of separate split systems, you would lose only one zone.
• Complexity and Cost of Installation: This is the most important point. Running long lines (freon pipes) from one point to all rooms requires wall chasing, routing communications through ceilings or floors. The cost of installing a multi-split system is usually 30-50% higher than installing separate "back-to-back" units.
• Single Operation Mode: All units in the system must work either for cooling or for heating. You cannot turn on heat in one room and cooling in another (this is possible only in expensive 3-pipe VRF systems, but not in domestic multi-splits).

Brand Choice: Overview of Market Leaders in Moldova

At Eurosanteh store, we have gathered a portfolio of brands that have proven their reliability in our climate conditions (hot summers and humid winters).

Mitsubishi Electric: The Standard of Reliability

The Japanese giant offers MXZ series systems. This is premium class equipment. Key advantages — incredibly quiet operation, highest energy efficiency (A+++), and the ability to work for heating at very low temperatures. Indoor units of Premium and Design series (in black, silver, or red) will become an interior decoration.

Gree and Haier: Price/Quality Leaders

Chinese manufacturers #1 in the world. Their multi-split systems (e.g., Gree Free Match or Haier Super Match) offer premium segment functionality for reasonable money. Inverter compressors, Wi-Fi control in standard configuration, self-cleaning systems, and availability of spare parts make them sales hits for apartments and small businesses.

Inventor and Other Budget Solutions

If the budget is limited, brands like Inventor offer reliable "workhorses". They might be slightly noisier than flagships or have simpler plastic, but they cope excellently with the main task of cooling and heating.

Technical Nuances: What to Consider When Designing?

Purchasing a multi-split system starts not in the store, but at the stage of rough renovation.

1. Line Length and Recharging

Each outdoor unit has a limit on the total length of lines (usually up to 60-80 meters for powerful models) and length to each unit (up to 20-25 meters). If lines are longer than the factory standard, Eurosanteh installers are obliged to perform system recharging with freon strictly by weight. Violation of this rule will lead to power loss and compressor failure.

2. Drainage Removal

Since indoor units are often located far from external walls, condensate removal becomes task #1. It often requires the use of special drainage pumps or routing drainage into the sewage system through a trap (siphon) so that odors do not penetrate the room.

3. System Power Supply

Unlike regular air conditioners, where power is often supplied to the indoor unit, in multi-split systems power (220V) is usually brought to the outdoor unit. A control cable is laid between the outdoor and indoor units. It is critical to consider this when wiring.

Tip from Eurosanteh Engineers: When selecting a system, always consider the simultaneity coefficient. If the total area of rooms requires 12 kW of cooling, but you know you will never turn on air conditioners in all rooms at full power simultaneously (e.g., living room during the day, bedrooms at night), you can take a 10 kW outdoor unit. This will save budget and increase inverter operation efficiency. Permissible overload on indoor units is usually up to 130% of the outdoor unit's nominal value.

FAQ: Frequently Asked Questions About Wall-Mounted Multi-Splits

Can I buy the outdoor unit and one indoor unit first, and buy the rest later?

Yes, this is possible. Free Match technology allows connecting units in stages. The main thing is to lay lines to all future installation points in advance during renovation and preserve them (seal the ends) so that moisture and construction dust do not get inside.

What happens if I turn one unit on heating and another on cooling?

The system will go into "Mode Conflict" error. Priority is usually given to the unit that was turned on first. For everything to work correctly, switch the entire system either to "Winter" mode (Heat) or "Summer" mode (Cool). In ventilation mode, units can work independently.

How economical are they in winter?

Modern inverter multi-split systems are very efficient. The SCOP coefficient can reach 4.0-5.0. This means that for 1 kW of electricity consumed, you receive 4-5 kW of heat. This is 4-5 times more profitable than an electric heater. However, at temperatures below -15°C, efficiency drops unless a special low-temperature model is chosen (e.g., Mitsubishi Zubadan).

Glossary

Multi-Split System

An air conditioning system consisting of one outdoor unit and several (2-5) indoor units connected in parallel.

Inverter

Compressor control type that smoothly regulates power rather than turning it on/off, ensuring temperature precision and energy savings.

Line (Freon Pipe)

Copper insulated pipes connecting the units, through which refrigerant circulates.

Simultaneity Coefficient

A parameter allowing connection of indoor units with total capacity exceeding the outdoor unit's nominal value to the outdoor unit, counting on the fact that they will not work at peak simultaneously.