Split Air Conditioning (Single & Multi Split)

What is split air conditioning?

Split air conditioning is a system in two halves: an indoor unit in the room and an outdoor unit outside, connected by pipework. A single split connects one indoor unit to one outdoor unit. A multi-split connects several indoor units to one outdoor unit (Mitsubishi Electric). Climate Flow Limited installs and services single and multi-split systems for homes and small commercial spaces across London and surrounding areas.

The indoor unit sits in the room and cools or heats the air there. The outdoor unit sits outside and lets the heat out.

Single split or multi-split: which suits your space?

A single split suits one room, such as a bedroom, home office, living room or garden office. A multi-split suits a home or premises with more than one room that needs cooling, because several indoor units share one outdoor unit.

The survey decides which one fits: how many rooms need cooling, where each indoor unit can go, and where the outdoor unit can sit with a route for the pipework back to each room. For a larger open space or a building with many rooms, a cassette system (an indoor unit set into the ceiling), a ducted system (an indoor unit hidden in the ceiling space, sending air to the rooms through ducts) or a VRF system (variable refrigerant flow, one outdoor unit serving many indoor units) may suit better, and the survey is where that is decided.

Can a split system heat as well as cool?

Daikin describes its wall-mounted range as heating and cooling through all seasons. Whether a particular model heats, and how it suits your room, is set out in the manufacturer's documentation and checked at the survey.

Where does the outdoor unit go?

The outdoor unit needs a place outside where it can let the heat out. The same Daikin range is designed to go on a roof, on a wall or in a garden. Where it goes on your property is decided at the survey, together with the route the pipework takes back to the indoor unit. If you live in a flat, it is worth checking with the freeholder, and with your local planning authority, before an outdoor unit goes on the building.

What does a split system installation involve?

A split system installation follows the same sequence whether it is one room or several. Someone needs to be on site to give access to each room and to the outside wall or roof.

1. Survey. An engineer looks at the rooms, the walls, where the outdoor unit can go and the route for the pipework.
2. Quote and layout. You get a quote showing the system, the unit positions and the pipe route.
3. Installation. The indoor unit goes on the wall, the outdoor unit goes on its bracket or base, and the pipework and cabling run between them.
4. Commissioning and handover. The system is tested and you are shown how to use the controls.

Signs your split system needs attention

A split system that is struggling usually shows it in one of these ways:

• the room is not cooling or heating the way it used to;
• water is dripping from the indoor unit;
• there is a new noise, rattle or smell;
• the indoor unit shows an error code or a flashing light;
• the outdoor unit does not run when the system is switched on.

Do not open the refrigerant circuit or add refrigerant yourself. In UK law it is illegal to work on F gas equipment (equipment holding fluorinated refrigerant gas, the gas that carries heat around the system) without the correct qualifications (GOV.UK, qualifications to work with F gas).

How often does a split system need servicing and leak checks?

Air conditioning holding F gas of 5 to 50 tonnes CO2 equivalent (a measure that combines how much refrigerant the system holds with how strongly that gas warms the climate) must be leak checked at least once every 12 months. Hermetically sealed systems (systems whose refrigerant circuit is permanently sealed, with no joints made to be opened) have no maximum period between leak checks unless they contain F gas equivalent to 10 tonnes of carbon dioxide (GOV.UK, checking F gas equipment for leaks). Whether a split system reaches that threshold depends on its refrigerant and how much it holds, and your engineer can tell you which applies to your unit.

Installing, servicing and leak checking stationary air conditioning all need qualified engineers, and a company that works on F gas equipment operated by others must be certified by an approved body (GOV.UK, company certification to work with F gas). Climate Flow is F-Gas certified.

Where split systems are used

Single and multi-split systems suit homes and small commercial spaces. We installed a split system for a family home in London, and a Mitsubishi Electric split system for a newly refurbished retail unit in Hillingdon.

Brands we install and service

We install and service air conditioning from Mitsubishi Electric, Mitsubishi Heavy Industries, Daikin, Fujitsu, Toshiba, Panasonic and Samsung.

Arrange a survey for split air conditioning

To arrange a survey for split air conditioning at your home or premises, contact Climate Flow Limited, 2 Engineers Way, Wembley, London HA9 0JS, on 020 3488 5452. We cover London and surrounding areas, and you can see everything else we do on our services page.

This guide is general information, not a survey or a quote for your site; every system is different, so an engineer needs to see yours before any work is priced.