The MLZ (left) and MTZ are both cleared for use with R407A and R407F

DENMARK: The lower GWP refrigerants R407A/F have been validated for use in Danfoss Maneurop reciprocating MTZ compressors and Danfoss scrolls MLZ.

The qualification plan encompasses Optyma Plus new generation and Optyma Slim Pack ranges for the end of February 2015.

R407A and R407F are both blends of R134a, R125 and R32 in different composition.  R407A is 40% R134a, 40% R125, 20% R32 and R407F is 40% R134a, 30% R125 and 30% R32.

Although not promoted as long-term replacements, R407A and R407F provide a lower GWP alternative to R404A in new and replacement systems. R404A is to be banned in Europe and is coming under increasing pressure worldwide due to its large GWP of 3922.

R407A has a GWP of around 2107 and the greater percentage of R32 gives R407F a slightly lower GWP at 1824.

Neither are “drop-in” replacements but R407A is compatible with the same oils, elastomers and plastics as R404A, the refrigerant it is designed to replace, but exhibits an increased compressor discharge temperature and greater glide. R407F has a similar cooling capacity to R404A and improved energy efficiency. Like R407A, R407F is fully compatible with the POE lubricants used in an R404A system and, in many cases, the original oil can be used.

Further details on R407A and R407F can be found in our review of R404A replacements R404A – the alternatives and in these separate Linde pdf documents for R407A and R407F.

Danfoss and its partner wholesalers can provide assistance to installers and OEMs in the selection and retrofit when switching to the new refrigerants with specific guidelines and selection tools.

Application guidelines and instructions for the MLZ and MTZ compressors are available at