Question 1

What is the difference between GWP and ODP?

Accepted Answer

GWP (Global Warming Potential) measures a refrigerant's 100-year warming impact relative to CO2=1. R-410A has GWP=2088, R-32 has GWP=675. ODP (Ozone Depletion Potential) measures stratospheric ozone destruction relative to R-11=1. Most modern refrigerants have ODP=0, but R-22 has ODP=0.055 and is regulated under the Montreal Protocol.

Question 2

Which refrigerants are banned under EU F-Gas regulations?

Accepted Answer

The EU F-Gas Regulation (2014 and 2024 revision) bans refrigerants with GWP≥2500 (e.g., R-404A: GWP=3922) in new equipment from 2020. From 2025, GWP≥150 refrigerants are restricted in small hermetic refrigeration equipment. R-32 (GWP=675), R-1234yf (GWP=4), and R-290 (GWP=3) are leading alternatives.

Question 3

What are the alternatives to R-22?

Accepted Answer

R-22 (HCFC, ODP=0.055) replacement options include: ① R-407C (GWP=1774, near drop-in properties), ② R-410A (GWP=2088, higher-pressure system required), ③ R-32 (GWP=675, mildly flammable A2L). For lower GWP, R-454B (GWP=467) is gaining traction. None are true drop-ins — oil change and system modifications are required.

Question 4

What are the pros and cons of natural refrigerants?

Accepted Answer

Natural refrigerants have negligible GWP and ODP. CO2 (R-744): GWP=1, requires transcritical cycle and high pressures (~13 MPa), highly efficient at low temperatures. Ammonia (R-717): GWP=0, toxic (B2L), excellent thermodynamic efficiency — dominant in industrial refrigeration. Propane (R-290): GWP=3, flammable (A3), charge-limited but widely used in domestic appliances.

Refrigerant Selection & Environmental Properties Tool

COP Index (Simplified Carnot Basis)