Most split air conditioners contain an F-gas refrigerant such as R32. Under the GB F-Gas rules, installing, servicing or removing one must be done by a certified engineer working for an F-Gas certified company. Small domestic units often fall below the size where regular leak checks are legally required, but they still need careful installation. Monobloc and portable units come sealed, so they don't need an F-Gas installer. Always ask to see the installer's certificates.
What are F-gases, and does my air conditioner use them?
F-gases are fluorinated greenhouse gases. Many are used as refrigerants, the fluid that carries heat between the indoor and outdoor units. If you have a split air conditioner, it almost certainly contains one.
The most common in new domestic units is R32. Older systems often use R410A. Both are much stronger greenhouse gases than carbon dioxide if they leak. R410A is roughly three times as potent as R32, which is a big reason the industry has moved away from it.
The rules measure refrigerant in tonnes of CO2 equivalent, not just kilograms. That is the weight of refrigerant multiplied by its global warming potential. It matters for leak checks, covered below.
Some newer appliances use natural refrigerants such as R290 (propane). These aren't F-gases, but they are flammable, so they need their own care when installed and serviced.
What do the F-Gas regulations say?
In Great Britain, F-gases are controlled by the Fluorinated Greenhouse Gases Regulations 2015 together with the retained version of EU Regulation 517/2014. Together, these are usually called the GB F-Gas regulations. They aim to cut emissions by preventing leaks and phasing down the most harmful gases.
For homeowners, the main points are:
- Certified people
- Only certified engineers may install, service, repair or decommission most split systems.
- Certified companies
- Businesses doing this work for others need a company F-Gas certificate too.
- No venting
- Refrigerant must be recovered, never released into the air.
- Leak checks
- Required at set intervals for larger systems, based on CO2 equivalent.
- Phasing out high-impact gases
- Rules limit high-impact refrigerants like R410A in many new small splits.
Who is allowed to install or service a split air conditioner?
An engineer who holds the right F-Gas personal certificate, working for a company that holds an F-Gas company certificate. Both are needed for paid work in your home.
The personal certificate shows the engineer has been trained and assessed in handling refrigerant safely. The company certificate shows the business has certified staff, the right tools and proper procedures. Connecting the pipework, pressure testing, pulling a vacuum and releasing or adding refrigerant all count as work covered by the rules.
The same applies at the end of a unit's life. Removing an old split system means recovering the refrigerant first, so it should be done by a certified engineer too. The refrigerant then goes for recycling or destruction, not into the air.
The electrical side is separate. A new dedicated circuit is notifiable under Part P of the Building Regulations, so it must be done by a registered electrician or approved through building control.
Can I buy and fit a DIY or pre-charged split unit myself?
Be careful. DIY split kits with pre-charged, quick-connect pipes are sold online, but the rules restrict how they can be sold and fitted.
In broad terms, the regulations say equipment like this, which isn't hermetically sealed and is charged with F-gases, should only be sold to end users where there is evidence it will be installed by a certified company. Some sellers ask for this, some say a certified installer is needed to keep the warranty, and some say little. The details are technical, so check GOV.UK or ask the seller in writing before you buy.
Even when the joints are designed for DIY, quick connectors can leak if they aren't tightened correctly, and there is no vacuum or pressure test to prove the joints are sound. A slow leak reduces performance over months and releases a greenhouse gas. Many certified installers won't take on a unit someone else has partly fitted, so ask first if that's your plan.
Do monobloc and portable air conditioners need an F-Gas installer?
No. Monobloc and portable units come factory-sealed, with all the refrigerant inside one casing. Installing them involves no work on the refrigerant circuit.
A portable unit just needs a socket and a window outlet for the hose. A through-the-wall monobloc needs two holes cut through the wall and sometimes a dedicated circuit, but no refrigerant pipework. They are less efficient and noisier than split systems, because all the noisy parts sit inside the room. If you only need occasional cooling in one room, that trade-off may be fine.
If a sealed unit develops a refrigerant fault later, any repair that opens the circuit still needs a certified engineer.
Does a home air conditioner need regular leak checks?
Often not, legally, but it is worth having it serviced anyway. Mandatory leak checks apply when a system holds refrigerant above certain thresholds measured in CO2 equivalent, starting at 5 tonnes for systems that aren't hermetically sealed.
For R32, that threshold works out at roughly 7kg of refrigerant. For R410A, it is roughly 2.4kg. Many single-room domestic splits hold well under these amounts, so they usually fall below the legal threshold. Larger multi-split systems, or older R410A units, may not. Your installer can tell you the charge from the unit's rating plate and whether leak checks apply.
Where checks are required, the interval depends on the size of the charge, with larger systems checked more often. An annual service still makes sense for small units. It catches small leaks, blocked drains and dirty coils before they cut efficiency.
What paperwork should I keep?
Keep everything your installer gives you, even if your unit is below the leak-check threshold. It helps with warranty claims, servicing and selling the house.
- Installation record
- Unit model, refrigerant type, charge and any refrigerant added.
- Installer's details
- Engineer's name and company F-Gas certificate number.
- Commissioning results
- Pressure test and vacuum readings, if provided.
- Warranty registration
- Many manufacturers need it registered and serviced to honour warranties.
- Service records
- Each visit, any leaks found and refrigerant added or recovered.
- Electrical certificate
- For a new circuit, plus building control notification.
Why does using a certified installer matter?
Because a split system only works properly, safely and efficiently if the refrigerant circuit is sealed and charged correctly. It also protects your warranty and keeps you on the right side of the rules.
A leak means lower cooling and heating output, higher running costs and eventually a failed compressor. Manufacturers commonly require installation by an F-Gas certified company, and an uncertified job can void the warranty. Enforcement in England sits with the Environment Agency, which can take action over breaches. Penalties mostly target businesses, but buying and fitting equipment the wrong way can still cause problems.
The GB rules apply in England, Scotland and Wales, though enforcement is done by different agencies. Northern Ireland follows the EU F-gas rules. The GB rules have also been under review, so check GOV.UK for the current position.
How do I check an installer's F-Gas certification?
Ask for two things before you agree to the work: the engineer's personal F-Gas certificate and the company's F-Gas certificate number. A genuine installer will give you both without fuss.
Company certificates are issued by approved certification bodies, and the certificate says which one. Most bodies have an online register or will confirm a number if you contact them. Check that the company name and address match the business quoting you, and that the certificate hasn't expired.
Each installation gets one fixed price agreed before work starts.
Questions
Can an electrician install air conditioning without F-Gas certification?
An electrician can do the electrical connection, but not the refrigerant work on a split system. Connecting the pipes, testing and releasing the refrigerant needs F-Gas certification. Some installers, like us, hold both, so one visit covers the whole job.
Is R32 being banned?
Not in domestic split systems at the time of writing. R32 has a much lower impact than R410A, which is why it replaced it in most new units. Future rules may push towards lower-impact refrigerants, so check the latest GB guidance.
Can my existing R410A air conditioner still be serviced?
Yes. Existing R410A systems can still be serviced and repaired by certified engineers. The restrictions mainly affect new equipment being placed on the market, not units already installed in homes.
Who is responsible for leak checks in a rented home or office?
Usually the operator, meaning whoever has control over the system. In a business that's often the owner or tenant running the equipment. For rented homes, it depends on the tenancy, so landlords should make it clear in writing.
What happens to the refrigerant when an old unit is removed?
A certified engineer recovers it into a special cylinder before the unit is disconnected. It is then recycled, reclaimed or destroyed. It should never be cut out or vented, which is illegal and harmful.
Do heat pumps follow the same F-Gas rules?
Air-to-air heat pumps are split air conditioners in practice, so the same rules apply. Air-to-water heat pumps that contain F-gases are covered too, although many modern models are sealed monobloc units and some use natural refrigerants.