The best air conditioning system is usually a wall-mounted split unit for single domestic rooms, and a multi-split or ducted system for larger commercial spaces or domestic multi-room properties. However, the ideal setup also depends on factors such as property type, room layout, energy efficiency goals, and installation options.
This guide will walk you through the most common types of air conditioning used in UK homes and commercial spaces, what they are, how they compare, and which might suit your needs best. From compact home gyms to open-plan commercial spaces, we’ll help you find the right system for your space, budget, and comfort.
Summary: What’s the Best Air Conditioning System?
The best air conditioning system for you depends on a number of different factors, including:
- Property type: Home, office, shop, or warehouse?
- Number of rooms: Single room or multi-zone?
- Installation options: Can external units be fitted?
- Energy efficiency goals: Do you want to reduce running costs?
- Smart controls: Do you need app or remote access?
Let’s dive into the different type, their pros, cons and where they’re best suited.
Quick Comparison Table of Different Types of Air Conditioning Systems
Here’s a quick comparison of the main air conditioning systems. This table gives you a high-level view of how each type stacks up in terms of suitability, efficiency, and installation, so you can quickly see which might be the best fit for your home or business.
| Table System Type | Best For | Installation Needed | Energy Efficiency | Appearance | Typical Use |
|---|---|---|---|---|---|
|
Split Wall AC Units
|
Single rooms in homes or offices
|
Yes (indoor & outdoor units)
|
★★★★☆
|
Compact wall-mounted
|
Bedrooms, lounges, studies
|
|
Wall-Mounted Multi-Split Systems
|
Multiple rooms, zoned control
|
Yes (usually 1 outdoor, multiple indoor units)
|
★★★★★
|
Discreet wall units
|
Homes, apartments, offices
|
|
Ceiling Cassette Systems
|
Larger, open-plan or commercial areas
|
Yes (ceiling-mounted)
|
★★★★☆
|
Flush, ceiling-integrated
|
Shops, offices, restaurants
|
|
Ducted Systems
|
Whole-building, seamless cooling
|
Yes (extensive install)
|
★★★★★
|
Hidden ductwork
|
New builds, large homes, commercial spaces
|
|
Portable Units |
Temporary or emergency use only |
No |
★★☆☆☆ |
Bulky, hose to window (in some cases) |
Rentals, short-term fixes |
Full Comparison of the Types of Air Conditioning Systems
1. Split Wall AC Units – Best for Single Rooms
Split systems are the most popular choice for individual rooms. They consist of one indoor unit mounted to the wall and one outdoor unit to expel heat. Quiet, efficient, and compact, they’re ideal for year-round comfort.
Pros
- Highly energy efficient
- Quiet operation
- Ideal for regular use in homes or offices
- Available with smart controls and eco modes
Cons
- Needs a suitable external wall for the outdoor unit
- Higher upfront cost compared to portable options
Best for: Bedrooms, lounges, studies, and home or garden offices
2. Wall-Mounted Multi-Split Systems – Best for Zoned Control
Multi-split systems allow several indoor units to connect to a single outdoor condenser, offering independent control in each room. These systems are discreet and perfect for buildings needing targeted cooling across multiple areas.
Pros
- Zoned temperature control across multiple rooms
- Only one external unit needed
- Energy efficient and quiet
- Flexible for growing setups
Cons
- Requires slightly more planning for indoor placement
- May incur higher installation cost than single splits
Best for: Homes, apartments, and offices with two or more rooms to cool
3. Ceiling Cassette Systems – Best for Open-Plan Areas
Ceiling cassette systems are fitted into suspended ceilings and deliver 360° airflow, making them an excellent choice for commercial or open-plan spaces. They’re unobtrusive and powerful, with smart options available.
Pros
- Flush to the ceiling for a clean look
- Even airflow across the room
- Quiet and space-saving
- Suitable for large or high-traffic areas
Cons
- Requires ceiling void for installation
- Installation can be more involved in retrofits
At Eaglereach, even when more involved retrofitting is required, we always handle the process with care and precision to minimise disruption.
Best for: Shops, offices, restaurants, and open-plan commercial spaces
4. Ducted Systems – Best for Seamless, Whole-Building Cooling
Ducted systems use concealed ductwork to deliver air through discreet vents in each room. They’re the most seamless option, providing whole-building comfort with minimal visible hardware.
Pros
- Unobtrusive and integrated design
- Consistent temperature control throughout
- Smart zoned options available
- Quiet and highly energy efficient
Cons
- Sometimes best suited to new builds or major refurbishments
- Higher initial investment compared to other systems
Best for: New builds, large homes, and commercial properties needing full-property coverage
5. Portable Air Conditioners – Best for Short-Term or Unusual Situations
Portable units are standalone and plug into a standard socket. Warm air is expelled via a hose through a window or door.
Pros
- No installation needed
- Can move between rooms
- Lower upfront cost
Cons
- High running costs
- Noisy operation
- Poor efficiency
- Hose must vent through a window or wall
Eaglereach’s expert view: While portable models seem convenient, they’re often a false economy. Unless you’re dealing with short-term use or listed building restrictions, a fixed unit offers better comfort and control.
What Makes a System Efficient?
Energy efficiency is typically measured using the British Thermal Unit (BTU) rating. A 12,000 BTU unit is suited to spaces of around 25–35 m². For smaller rooms like a home office, a 9,000 BTU unit may be more appropriate.
To maximise energy savings, look for:
- A high energy efficiency rating (EER/SEER)
- Smart features like remote control or app access
- Sleep mode for overnight use
- User-friendly controls that simplify usage
Pro tip from Eaglereach: Oversized or undersized units will incur higher costs in the long run. Always size your air conditioning unit based on accurate measurements and usage patterns.
Features Worth Considering for Your Air Conditioning Setup
Beyond system type, the right features can make a big difference to day-to-day comfort, energy use, and control. Here are some of the most useful options to look for when choosing your air conditioning setup:
- Smart controls: Control your air con remotely or by voice
- Quiet modes: Essential for bedrooms or meeting rooms
- Sleep mode: Adjusts temperature gradually overnight
- Dehumidification: Removes excess moisture, especially helpful in UK summers
- Heat pump option: Provides both heating and cooling
Is Air Conditioning Worth It in the UK?
Despite our traditionally mild climate, UK summers are getting hotter. Air conditioning isn’t just about cooling, modern systems also purify air, remove moisture, and provide warmth in winter.
Professionally installed systems can even reduce energy bills by offering a more efficient alternative to electric or gas heating.
How Much Does It Cost to Run Each System?
Running costs vary by system type, energy efficiency, and how often you use it. Based on average UK usage, here’s what to expect:
- Split Wall Units: Around 20–35p per hour, or £1.60–£4 per day for 8 hours of use
- Ceiling Cassette Systems: Around 30–50p per hour
- Multi‑Split Systems: Roughly 30–50p per hour across all rooms combined
- Ducted Systems: Typically 40–60p per hour
To compare different system types in more detail, including cost-saving tips and how they stack up against electric or gas heating, see our full guide on running costs.
Final Thoughts
Choosing the right system depends on your building type, usage, design preferences and efficiency goals. Each style, from split wall units to full ducted systems, has its own advantages, installation needs, and cost profiles.
We’ve covered the key differences in system types, installation ease, and energy performance. You also know what running costs to expect and where to go for deeper insights.
At Eaglereach Mechanical, we help you make smart choices, install to precision and keep things running smoothly even after installation. Whether you’re equipping one room or planning full-property installation, we offer free consultations and bespoke recommendations.
Ready to get started? Contact us today to arrange a free site survey or speak with one of our engineers about the ideal system for your space.
FAQs
Which type of air conditioner is the most energy-efficient?
Split and multi-split systems typically offer the best energy efficiency, especially when sized correctly and used with smart controls.
Which AC unit is cheapest to run?
Fixed split units are generally cheaper to run than portable models due to higher efficiency ratings.
Which AC brand is most reliable?
Brands like Daikin, Mitsubishi, and Panasonic consistently perform well. Eaglereach recommends based on the space, usage, and support network in your area.
Do portable units need to vent out a window?
Yes, most portable models must expel hot air via a hose. If this isn’t possible, a fixed system may be more suitable.
