How Long Does Air Conditioning Installation Take?

For most homes in Surrey, a single split system (one outdoor unit serving one indoor unit) is a one-day job. A qualified two-person team will usually arrive in the morning and have you cooling that afternoon.

A multi-split system serving three or four rooms typically takes one to three days, because each indoor unit needs its own pipe run, drainage and electrical connections back to the outdoor condenser. Ducted whole-home systems are a different scale of job: expect a week or more, and they are usually planned around decorating or building work because of the ductwork in ceilings and voids.

The visit follows a fairly predictable rhythm. First, the engineers protect the work areas with dust sheets and confirm the agreed positions for the indoor and outdoor units. Next they mount the indoor unit(s) on the wall and fix the outdoor condenser to a wall bracket or ground feet.

Then comes the part that takes the most time: running the refrigerant pipework, drainage and cabling between the units, usually through a neat core-drilled hole in the wall. Once everything is connected, the system is pressure-tested and vacuum-evacuated to remove moisture and air before the refrigerant is released. Finally the engineers commission and test the system, run it in both cooling and heating, and show you how to use the controller. F-Gas regulations require that refrigerant handling is done by a certified engineer, so this stage is not rushed.

The biggest factor is the number of indoor units and how far each one sits from the outdoor condenser. Long pipe runs across a house, or routes that go up through floors and lofts, add hours. Property type matters too: a modern home with easy cavity access is quicker than a solid-wall Victorian terrace needing careful core-drilling and tidy external trunking.

Other things that affect timing include outdoor-unit access (a first-floor or awkward rear position may need scaffolding or a longer lift), the electrical supply (a new dedicated circuit adds time), and the weather. A well-surveyed job rarely overruns; most delays come from surprises that a proper site survey beforehand would have caught.

Not much, but a few things help the day run smoothly. Clear access to the walls where units will be mounted and to the outdoor condenser position, and move any furniture or fragile items out of the way. If the route passes through a loft or cupboard, make sure it is reachable.

You should also have settled the unit positions at the survey stage rather than on the day, and checked whether your install needs planning permission. Many domestic installs are permitted development where the outdoor unit meets MCS 020 noise limits (no louder than 42 dB(A) at the neighbour's window), but conservation areas, listed buildings, flats and Article 4 areas usually need consent first. In heritage-rich parts of Surrey, sorting this out before the day saves the most time of all.

Immediately. Once the system is commissioned and tested at the end of the install, it is ready to run that same day, in both cooling and heating modes. An air conditioner is a reverse-cycle air-to-air heat pump, so the same unit that cools you in July will warm a room efficiently in winter.

Your engineer will register the warranty, leave you the controller instructions, and explain the annual service that keeps the warranty valid and the running costs low. There is no curing or settling period to wait out, you simply switch it on.