R404A vs R449A UK: Commercial Refrigeration Replacement Guide
R449A (Opteon XP40) is one of the two leading drop-in replacements for R404A in UK commercial refrigeration. With R404A’s GWP of 3,922 driving up prices under F-Gas quota restrictions, R449A (GWP 1,397) offers a 64% GWP reduction with similar performance and A1 safety class.
R404A vs R449A: Key Properties
- GWP: R404A 3,922 | R449A 1,397 (64% lower)
- Safety: Both A1 non-flammable
- Temperature glide: R404A ~0.5°C | R449A ~5.2°C — must charge as liquid
- Capacity: Very similar at medium temperatures; slight reduction at very low temps
- Efficiency: R449A typically 3–5% better COP than R404A
- Discharge temp: R449A runs 3–6°C higher — verify compressor limits
- Oil: POE oil required; flush system when changing from R404A
R449A vs R448A
R449A is preferred for supermarket display case retrofits; R448A for cold stores and walk-ins. GWP and performance are nearly identical. Follow your OEM’s recommendation for the specific equipment.
Retrofit Procedure: R404A to R449A
- Recover all R404A using certified recovery equipment
- Flush system oil — remove alkylbenzene/mineral oil, replace with POE
- Pressure test and evacuate to 500 microns
- Charge R449A as liquid (siphon/inverted cylinder)
- Adjust TXV — R449A’s zeotropic properties usually require TXV adjustment
- Monitor discharge temp; update labels and F-Gas records
Servicing existing R404A systems? R404A 10.9 kg from Refrigerant Gas Supplies Ltd — F-Gas compliant, next-day UK delivery. Contact us for trade account pricing.
Frequently Asked Questions
Is R449A a true drop-in for R404A?
Equipment-compatible but zeotropic — must be charged as liquid and TXV adjustment is typically needed. A POE oil flush is recommended. Not zero-work but far simpler than a full system redesign.
Does R449A need different recovery equipment?
Standard A1 HFO-blend rated recovery machines (most from 2018+) are compatible. Check your machine’s approved refrigerant list.
How much R449A vs R404A by weight?
Typically 90–95% of the R404A charge weight. Always verify with OEM conversion data for the specific equipment.