ReFreeX ™ refrigeration method
We use new, patented and improved "ReFreeX" refrigeration method. Why "ReFreeX"?
- "ReFreeX" refrigeration method reduces refrigerant charge in system by up to 80%;
- Using of "ReFreeX" reduces electrical power consumption by up to 50%;
- Less lubricating oil in the system;
- Expansion of refrigerant is controlled by pulsing solenoid valve - no TEV required;
- There is no need to obtain sertificates for liquid receiver;
- Completely digital control of refrigeration system;
- System can be controlled via remote computer - from your home, office or anywhere else where the internet access point is available.
Up to 50% reduction of electrical power consumption during cold weather period
In conventional refrigeration systems, the operation principle of which is based on mechanical thermoexpansion valves (TEV), in order to keep the cycle within the working range of TEV, it is necessary to maintain high temperature of condensation(about 40 C) to ensure that proper amount of refrigerant is present in the liquid side of the system. This is crucial, since drop in liquefied refrigerant amount will reduce the capacity of the system, leading to high electricity consumption.
Assuming standard condensation temperature of 40 C (it should be slightly higher than ambient air temperature during hot summer days), the required condensation pressure will be 18.5 bar for R404A refrigerant. Obviously, the higher pressure is being created by the compressor, the higher is power consumption. During periods when the ambient temperature is lower, we could potentially have our condensation temperature and pressure decreased, requiring less work of compressor, however this is impossible due to technical limitations of TEV-based system that were previously described, as with decrease of condensation pressure such phenomenon as self-regulation effect will occur, leading to capacity and efficiency COP(coefficient of performance – ratio between power consumption and cooling power provided by the system) losses.
Contrary to conventional systems, mechanical TEVs aren’t utilized in ReFreeX, being substituted with digitally-operated pulsing solenoid valves, essentially removing the technical limitations described above. Such change makes system adaptive to the environment it operates in, and condensation temperature(hence condensation pressure) is constantly being adjusted to ambient air temperature, making it possible to obtain higher cooling capacity with less power consumption, drastically increasing the COP.
In order to illustrate this more clearly, let us give an example. For instance, we assume a system with following parameters: compressor Bitzer 4PCS-10.2Y-40P, refrigerant R404A, temperature of evaporation of -10 C, superheating 7 K, condensation temperature 45C. At such conditions we can obtain as much as 21.6 kW of cooling capacity with 10,9 electricity consumption. That leaves us with COP of only 1,98.
Let us keep the same input parameters, with a minor alteration – decrease of condensation temperature to 30 C. As a result, condensation pressure drops to 14 bar, cooling capacity increases to 29.7kW, power consumption decreases to 9.37, what results in 50% increase of efficiency with COP being equal to 3,17.
If we make one step further and decrease condensation temperature by another 10 degrees (to 20*C), pressure of condensation will be just 11 bar, cooling capacity will increase to 35.1 kW while electricity consumption will drop to 7.96. COP = 4,41 (almost 2.5 times as higher than initial)
And, finally, at condensation temperature of 10*C liquid saturation pressure magnitude will be 8 bar, with 40.4 kW cooling capacity and 6.5 kW electricity consumption. The COP is 6.24, which means three times as higher efficiency if compared to conventional TEV-based system(keeping the same condensation temperature and pressure regardless of conditions change)
Calculations are based on official "Bitzer" software.
Refrigerant charge reduced up to 80%
Additionally, when mechanical TEV is utilized, similar phenomena occur on evaporator’s side, since heat load in a cold-room is variable (loading/unloading, machine and personnel operation, door opening, etc). In order to compensate for such fluctuations, a liquid receiver is used, ensuring required refrigerant flow through the TEV. In ReFreeX method refrigerant expansion begins right after the solenoid, and refrigerant superheating is being controlled and measured by electronic controller. Therefore, a liquid receiver in such system will be redundant, and thus, it isn’t installed, reducing the refrigerant charge by up to 80%.