What is CO₂ equivalent (tCO2e)?

CO₂ equivalent expresses the global warming potential of a refrigerant charge in terms of how many tonnes of CO₂ would have the same warming effect. It’s calculated as: charge (kg) × GWP ÷ 1000 = tonnes CO₂e. For example, 3.5 kg of R410A (GWP 2088) = 7.3 tCO₂e.

How often do I need F-Gas leak checks?

Under the F-Gas Regulation (retained in UK law post-Brexit): below 5 tCO₂e = no mandatory checks, 5-50 tCO₂e = annual checks, 50-500 tCO₂e = six-monthly checks (or annual with leak detection), above 500 tCO₂e = quarterly checks (or six-monthly with leak detection).

What is the GWP of common heat pump refrigerants?

R410A = 2088 (most common current ASHP refrigerant), R32 = 675 (increasingly used in new heat pumps), R290 (propane) = 3 (very low GWP, growing in use), R134a = 1430 (older systems). The industry is transitioning to lower-GWP options under the F-Gas phase-down schedule.

What records do I need to keep?

For systems containing 5+ tCO₂e, you must maintain an F-Gas logbook recording: refrigerant type and quantity, dates and results of leak checks, any refrigerant added or recovered, the identity of the certified technician, and details of any leaks found and repaired.

Who can work on F-Gas systems?

Only personnel holding a valid F-Gas certificate (Category I-IV as appropriate) can install, maintain, service, repair, or decommission F-Gas equipment. Companies must hold an F-Gas company certificate. This applies to air conditioning, heat pumps, and refrigeration systems containing fluorinated greenhouse gases.

TradeCalculator

F-Gas Calculator — CO&sub2; Equivalent & Leak Checks

Calculate CO&sub2; equivalent from refrigerant type and charge weight. Determine F-Gas leak check frequency thresholds and record-keeping requirements.

Refrigerant Type

Select refrigerant (GWP shown)

Charge Weight per Unit

Refrigerant charge per unit

Number of Units

Number of units on site

How We Calculate This

This calculator determines the CO&sub2; equivalent of a refrigerant charge and the resulting F-Gas Regulation compliance requirements including leak check frequency thresholds.

Calculations

CO&sub2; equivalent: Charge (kg) × GWP ÷ 1000 = tCO&sub2;e
Leak check thresholds: 5, 50, 500 tCO&sub2;e
Annual leak estimate: Charge × leak rate (%)
Phase-down: GWP ≥ 2500 banned in new equipment

Frequently Asked Questions

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Last updated: March 2026

All calculations are estimates. Verify with your supplier.