Most wall splits want their own electrical supply. If the consumer unit has a spare way and the cable route is short, a new circuit is often a high-hundreds illustration in 2026, sometimes less on a very simple run, added to the air conditioning install. If the board is full, obsolete, or cannot take the load, replacing the consumer unit moves the electrical bill into the high hundreds or the low thousands on its own. That work in a dwelling is for a Part P competent person who can certify it. This is not a wiring tutorial. Refrigerant work remains a separate F-gas task. The electrician and the air conditioning installer need one plan.
A spare way, or a board that has to go
The survey looks at the board, the main fuse, the earthing and the route to the outdoor isolator and the indoor unit. A modern board with space is the kind case. A rewireable fuse board, a board with no spare ways, or signs of overheating is the expensive case, because the safe answer is often a new consumer unit rather than a clever extra. Manufacturers specify the supply. The competent person designs it. Do not buy a breaker online and do not run a flex from a socket as a permanent feed. Quotes should separate electrical certification from the heat pump price so you can see it. Ask whether a spare way exists before you compare brands. Outdoor isolators need a sensible, weatherproof position.
A short, straightforward new circuit from a healthy board is commonly in the low to high hundreds as an illustration, depending on cable route, floors and whether decoration is included. A consumer unit replacement, bonding upgrades and a long run to a garden office can land in the high hundreds to low thousands. London parking and occupied houses add time. Those figures move with what the electrician finds, not with the air conditioning logo. Two heat pump quotes can match while the electrical allowances differ by a board change. Ask both to assume the same board, or to survey it. On a healthy board, a simple route is often a high-hundreds illustration or below in 2026. A new consumer unit can cost as much as a chunk of the install. Permanent splits are not specified to plug into a normal socket.
Part P, the certificate and the F-gas visit
In England, notifiable electrical work in the home, including many new circuits, should be done by a person registered to self-certify under a competent person scheme, or by an application through building control. GOV.UK Approved Document P is the building regulations guidance. You want a certificate at the end, especially in a rental or a sale. New circuits in dwellings are building regulations electrical work. The F-gas company may employ that electrician or may ask you to appoint one. Either model works if the isolator position, the start date and the certificate are agreed. Ask who signs the electrical certificate. The F-gas installer does the electrics only if they are also the competent person, or they bring one. Garden offices and outbuildings are where undersized existing cables hide. Survey them. Do not extend a lighting circuit because it is nearby. Energy Saving Trust describes the air-to-air heat pumps that need this supply.
Frequently asked questions
Can the air conditioning plug into a normal socket?
Permanent splits are not specified that way. Expect a dedicated supply designed and certified by a competent person.
How much is a new circuit compared with the unit?
On a healthy board, often a high-hundreds illustration or below in 2026 for a simple route. A new consumer unit can cost as much as a chunk of the install.
Does the F-gas installer automatically do the electrics?
Only if they are also the competent person for the electrical work, or they bring one. Ask who signs the electrical certificate.
Core buying guides
Start with these high-intent guides, then dig into the rest of the library.
Related guides
Sources and further reading
How this guide was prepared
This guide was written by the Local AC Installers Editorial Team. We compare official guidance, legislation and established consumer information, separate general information from project-specific advice, and show publication dates and sources. We do not accept installer accreditation claims at face value.