R448A Refrigerant UK: Solstice N40 Guide for Commercial Refrigeration

R448A (Solstice N40) is a low-GWP HFO/HFC blend with a GWP of about 1,387 – roughly 65% lower than R404A. It is one of the most widely adopted R404A replacements for UK supermarket and commercial refrigeration, working across both low and medium temperature. This guide covers its properties, retrofit suitability and handling.

What is R448A?

R448A is a blend of R32, R125, R134a, R1234yf and R1234ze. The inclusion of HFO components gives it a much lower GWP than R404A while maintaining strong efficiency, which is why it is favoured by major food retailers transitioning away from high-GWP gases.

R448A key properties

Property	Value
GWP	~1,387
Safety class	A1 (non-flammable)
Temperature glide	Moderate (~5K)
Application	LT and MT commercial refrigeration
Replaces	R404A, R507A, R22

Why choose R448A?

• Around 65% lower GWP than R404A, easing F-Gas quota exposure.
• Good energy efficiency, often improving on R404A in medium temperature.
• A1 non-flammable, so standard handling (no A2L charge-limit calculations).

Compare it directly with R449A and the other options in our R404A replacements guide.

Retrofit and handling notes

• Change oil to POE when retrofitting from R404A and confirm oil return.
• Moderate glide – charge as liquid and recover/recharge fully after a leak.
• Replace the filter-drier and recheck expansion device sizing.
• Recover all R404A first; never mix refrigerants.

Buying refrigerant in the UK

Refrigerant Gas Supplies Ltd supplies F-Gas compliant refrigerant to certified UK engineers, including R404A for existing systems – browse the full refrigerant gas range. F-Gas certification is required to purchase.

Frequently asked questions

What is R448A used for?

R448A is used in low and medium temperature commercial refrigeration as a low-GWP replacement for R404A, R507A and R22, especially in supermarkets.

What is the GWP of R448A?

R448A has a GWP of about 1,387, around 65% lower than R404A.

Is R448A a drop-in for R404A?

R448A is a recognised R404A retrofit, but it typically requires an oil change to POE, a new filter-drier and component checks. Always follow manufacturer guidance.

Is R448A flammable?

No. R448A is classified A1 – non-flammable – so it uses standard handling without A2L charge-limit calculations.