Air Conditioning Installation

Most air conditioning in UK homes and small offices is a split system: an indoor unit and an outdoor unit, joined by refrigerant pipes, a drain and a cable.

Indoor units can be wall-mounted (the most common), floor-standing consoles, or ceiling cassettes for offices with suspended ceilings. Split air conditioning installation is quieter than a portable unit because the compressor sits outside.

For offices, shops and restaurants, the electrical side is planned with our commercial electrical installation service.

Yes, most modern split systems can. They are reversible, which makes them air-to-air heat pumps: in heating mode the system takes heat from the outside air and releases it indoors, even on cold days. That makes them a useful way to heat a home office, garden room or extension that is hard to reach with the central heating.

An air-to-air system heats the air in the room only. It does not provide hot water or feed radiators; that needs a different type of heat pump.

Air conditioners are rated by cooling output, in kilowatts (kW) or as a BTU rating. A unit that is too small never quite cools the room; one that is too big switches on and off frequently and controls humidity poorly. The right size depends on room size and ceiling height, sun and glazing (south and west-facing rooms, bi-folds and roof lights), insulation (loft rooms heat up quickly) and how the room is used. Typical wall-mounted units for bedrooms and small offices start at around 2.5 kW of cooling. We size each room at the survey.

• Indoor unit: High on a wall where the air can spread, not blowing straight onto a bed or desk, and near an outside wall to keep the pipe run short.
• Outdoor unit: On wall brackets, a solid ground base or a flat roof, with clear space for airflow and servicing.
• Pipe run: Pipes, drain and cable pass through a small core-drilled hole and run in neat trunking, within the manufacturer's length limits.
• Condensate drainage: Cooling takes moisture out of the air. It drains by gravity to an outside drain or waste pipe, or through a small condensate pump.
• Noise and neighbours: Outdoor units hum while running, so we place them away from neighbours' windows where possible, on anti-vibration mounts.

Any marks on the wall can be made good through our painting service.

It depends on the property and where the outdoor unit goes. Indoor units do not need planning permission, but an outdoor unit changes the outside of the building. Some installations on houses need no application, within limits on size, position and noise; others need permission. Extra controls apply to:

• Flats and maisonettes: You will usually need the freeholder's consent, and often planning permission.
• Listed buildings: Listed building consent is normally needed.
• Conservation areas: Units facing the street are more likely to need permission.

We check the position at the survey; where there is any doubt, confirm with your council before installation.

Most systems need their own electrical supply from the consumer unit, with a local isolator by the outdoor unit. A new circuit is notifiable work, so it is installed through our domestic electrical installation service and certified through one of the routes the building regulations allow.

The refrigerant pipework is pressure-tested, evacuated to remove air and moisture, and then charged. This refrigerant work is carried out by an F-gas certified engineer, as the law requires, because refrigerant gases must not be released into the atmosphere.

• Clean the filters: They lift out of the indoor unit and can be vacuumed or rinsed, as often as the manufacturer recommends.
• Keep the outdoor unit clear of leaves, plants and stored items.
• Regular service: An engineer cleans the coils and drain, checks for refrigerant leaks and tests the controls. Manufacturers commonly recommend a yearly service.

A unit that drips indoors or smells musty usually needs its drain or filters cleaned.