Makro stores retrofit to Solstice N40

Wholesale retailer Makro has replaced the high-GWP refrigerant R404A with Honeywell's Solstice N40 (R448A) at two of its Spanish stores.

Makro, part of the Metro Group, has more than 2,700 employees at 37 stores across Spain and boasts almost 1 million registered users.

Contractor Catri carried out the retrofit at the Leganés store, Madrid, and the move has resulted in a number of benefits, including:

• R448A shows improved performance compared to R404A
• Lower energy consumption in both low and medium temperature systems
• A reduced GWP – 66% lower than R404A, giving lower emissions as well as lower maintenance costs due to the lower GWP tax in Spain
• Retrofit was completed without incident, with R448A a direct replacement of R404A

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José María de Santos, refrigeration manager at Makro, said: “N40 performance is good and set points were achieved immediately after retrofit.  We will continue to monitor and measure energy consumption for a long period to have reliable data about savings and consider them for future plans.”

Rafael Matarranz, manager at Catri, said: “It was a real challenge to make the conversion in the planned time, working shifts and with up to 60 technicians in the plant. The easy handling of R448A, the fact that it is a direct replacement and the excellent operational strategy defined for the job together with Makro, helped in minimising the time.”

Refrigerated stock from the medium temperature cabinets and cold rooms, were moved to a nearby Makro logistics centre, whilst the products from the low temperature cabinets and walk-in freezers were kept in 2 x 13m long refrigerated trucks.

Simple adjustment of all refrigeration controls saw the expansion valves closed by one turn, with superheat settings adjusted to meet the demands of the system.

Even though the discharge temperature of R448A is very close to that of R404A, due to the extreme peak temperatures in summer Makro decided to add extra mitigation in both low and medium temperature with ChillBooster in both condensers.

Following the success of the project in Leganés, the Makro store in Santander was also  retrofitted from R404A to R448A.