This choice of R-427A was motivated by the successful experience at the Géant Casino in Gap[1]. The low investment required in terms of this fluid confirmed their choice and allows them to keep the equipment in service without needing to replace the parts (compressors, exchangers, piping, regulators, electrical supply, etc.).
This conversion was carried out by Johnson Control Grand Est in collaboration with Climalife for its offer of all-encompassing solutions: supply of the R-427A, recuperation bottles, oil and treatment of the recuperated R-22.
The challenge of this operation was to avoid closing the hypermarket and to carry out the conversion in less than 48 hours despite the harsh weather conditions.
As a result, Johnson Control Grand Est called in Climalife’s services team to strengthen its operational team and provide adapted equipment.
To ensure the smooth running of the operation, a retrofit preparation phase was implemented according to the following method:
- One month before the retrofit, a sample of the oil was taken for a Periodic Diagnosis of Oil (DPH), after which the Johnson Control team drained the Shell Clavus SD2212 semi-synthetic oil from the six Bitzer compressors and replaced it by Mobil EAL ARCTIC 46 Polyolester oil.
- For a period of 1 month the equipment functioned with the R-22 and Mobil EAL 46 oil to clean and evacuate the semi-synthetic oil present in the installation.
- 5 days before the conversion, another oil sample was taken for DPH, 2nd draining and change of the electro valves, manual valves, hoses, and dehydrator cartridges to avoid possible leaks with the POE – HFC pair.
- Weekend of 30 & 31 January 2010: retrofit, Climalife’s Services team works alongside the Johnson Control team according to the specifications defined by Géant Casino.
The hypermarket aisles are empty and their contents stored in refrigerated trucks to respect the cold chain. The installation has been shut down. The team recuperates the R-22 by segmentation of the circuit, which makes it possible to isolate zones and consequently to change the valves, seals and filters that could not be changed while the installation was pressurised.
The recuperation times for the Profroid condensing unit were longer than expected: it was impossible to directly connect up to the condenser to rapidly recuperate the liquid and low exterior temperature phase (-8°C).
To facilitate the transfer and decrease the pressure in the recuperation bottles, they were stored in a cold room before and during the operation.
The installation was then fully drained down.
The R-427A was then introduced and the equipment started up again. The compulsory labels identifying the fluid contained in the installation were apposed as per the regulations in force.
After having lowered the temperature of the glass units and checked that the system was functioning correctly, the aisles were restocked and everything was ready for the hypermarket to reopen its doors on the Monday. Finally, another oil sample was taken for DPH.
Géant Casino, in agreement with Johnson Control, will ask Climalife to regenerate the R-22 as set down in European regulation no. 1005-2009, since the analysis of the product has confirmed this possibility. These regenerated quantities will allow Géant Casino to maintain the existing installations that require it and will simplify the planning of other due conversions.
The Géant Casino management and the CSA research and development department were satisfied with the operation and congratulated Johnson Control for the way in which the specifications were respected.
The partnership between Climalife and Johnson Control ensured the efficient preparation of the retrofit operation in a given time and made it possible to manage the challenge by rotating the teams. This success was down to excellent cooperation between qualified technicians.
Description of the installation
PROFROID Condensing Unit with 6 Bitzer Compressors.
Reference: CR6 CH 300 XC.
Original fluid refrigerant: R-22, original oil used: SHELL Clavus SD2212
|
|
Before the conversion |
After the conversion |
|
Refrigerating power |
65 kW |
65 kW |
|
Type of compressor |
BITZER 6F50.2Y hermetic accessible pistons |
|
|
Evaporation/condensation temperature |
-12°C / +40°C |
-15°C / +40°C |
|
Evaporation/condensation pressure |
2.3 b / 14,5 b. |
2,2 b / 14,5 b |
Installation Technician: Johnson Control Grand Est, Dijon: Thierry Montaron
Géant Casino: After Sales Operating Manager France: Yves Brisson
Research Consultancy: Cooling System Assistance: M. Gaudin
Photos: Climalife
Author : E Kugener
[1] (see case study ‘450 Kw of direct refrigeration reconverted for a Casino‘ on climalife.dehon.com/technical references, the first retrofit carried out in France with the R-427A.