F-Gas certification explained: what it means and why it matters

Every NexusAC install is carried out by an F-Gas certified engineer. Here's what that certification actually covers, and why it isn't optional.

What is F-Gas certification?

F-Gas certification is a legal qualification required for anyone in the UK who installs, services, or decommissions equipment containing fluorinated greenhouse gases — including the refrigerant used in air conditioning and heat pump systems. It's not a badge of quality on top of the legal minimum; it is the legal minimum for this work.

Why it's a legal requirement, not a nice-to-have

It's illegal for anyone without F-Gas certification to connect, vacuum, or release refrigerant gas lines. This isn't just red tape — refrigerant gases are potent greenhouse gases if released into the atmosphere, so improperly handled installs cause real environmental damage on top of the legal risk to whoever did the work.

What a certified engineer actually does differently

• Vacuums the lines properly before charging, removing moisture and air that would otherwise damage the system or reduce efficiency.
• Handles refrigerant recovery and disposal correctly rather than venting it, which is both illegal and environmentally damaging.
• Commissions the system properly — checking pressures, flow rates and performance — rather than just connecting pipes and switching it on.
• Issues an F-Gas certificate confirming the work was done to standard, which you should keep with your system's documentation.

How to check an engineer actually holds it

Ask directly for their F-Gas or REFCOM certification number before work starts — a legitimate engineer will have this readily available. Every engineer in the NexusAC network is verified before they're sent to a job, and every quote includes commissioning and your F-Gas certificate as standard, not as an add-on.

Commercial systems have extra requirements on top

Commercial installations carry additional F-Gas obligations beyond the install itself — regular leak checks (every 3, 6 or 12 months depending on refrigerant volume) and a compliance logbook recording every service and repair. See our guide on planning permission and regulations for more on how domestic and commercial rules differ.