Case studies

CA Warehouse Mansfields / Great Britain

Planning / Implementation / Main components: International Controlled Atmosphere Storage and SRS Frigadon with support of Re-phridge
Refrigerant: Propene (R 1270)
System start-up: 2008

The British fruit grower Mansfields stores apples and cherries in a controlled atmosphere so that they will be available in top quality all year round regardless of when they were picked. For refrigeration the family company uses a secondary refrigerant system with propene (R 1270). Re-phridge provided the specialist support for the safe application of the hydrocarbon refrigerant.


Mansfields wanted an efficient, HFC-free refrigeration system for the warehouse in Chartham near Canterbury.


The refrigeration experts International Controlled Atmosphere Storage and SRS Frigadon designed a propane secondary refrigerant system with an output of 1,150 kW. Five air-cooled factory-assembled packages charged with altogether 90 kg propene provide refrigerating energy for the secondary circuit at a temperature of -9°C. A brine mixture of water and salt is used as the secondary refrigerant. The circuit is filled with 30,000 l and works at an operating pressure of only 1.5 bar to cool the heat transfer fluid down to -3°C. The brine is pumped to the 36 controlled atmosphere cold storage rooms which are kept at a constant air temperature of -0.5°C and 1.5°C. The secondary refrigerant also cools the preparation and loading areas. The system design minimises the quantity of refrigerant and guarantees an ESEER (European Seasonal Energy Efficiency Ratio) of more than 4.2, although based on local conditions the real seasonal cooling COP (coefficient of performance) is around 6.

Technical data:


Type of system Secondary Refrigerant System
Refrigerant: Propene (R 1270)
Refrigerant charge 90 kg
Secondary refrigerant


Evaporating temperature

- 3 °C

Condensing temperature 0 °C
Cooling capacity 1.150 kW
Main components Five air-cooled factory-assembled packages, forced and natural convection brine coils
Special features / Comments The brine coils in the warehouses are defrosted by Off Cycle Defrost. This entails interrupting the refrigeration process so that the brine absorbs heat from the ambient air which is used for defrosting. This method prevents the products being cooled from absorbing unnecessary heat and saves energy.

SRS Frigadon Ltd
Mark Varney
6 Church Green, Atherstone on Stour
Stratford on Avon, CV37 8NE
United Kingdom
Phone: +44 1789 450 982
Fax: +44 1789 450 207
Mail: This email address is being protected from spambots. You need JavaScript enabled to view it.

Daniel Colbourne
PO Box 4745
Stratford-upon-Avon, CV37 1FE
United Kingdom
Phone: +44 (0)1789 26 82 85
Mail: This email address is being protected from spambots. You need JavaScript enabled to view it.