The currently valid regulation EU 517/2014 accounts for the extended use of flammable refrigerants of classes A2 and A3 in practice.
The Institute of Air Handling and Refrigeration supports clients implementing these refrigerants in their products.
Therefor a test bench for load simulation of compressors of up to approx. 25 kW fuelled with propane was developed and produced in 2019 and brought into service in 2020.
Two scenarios of use are possible at the test bench:
1. Power measurement according to DIN EN 13771-1: According to DIN EN 13771-1 and DIN EN 12900, refrigeration capacity, drive power, CoP, volumetric efficiency and quality grade can be determined for a predefined characteristic use map of single-stage compressors – especially for the flammable A3 refrigerant propane! The refrigerants A2/L: R452B, R32, R1234yf, R1234ze are also approved.
2. Load cycle test LTT500: The thermal/mechanic long-term behaviour and the interaction between compressor, refrigerant (A1, A2/L and A3) and oil can be tested under predefined changeable loads within the characteristic use map and during the exceedance of legitimate operation parameters (on/off cycles, reduced overheating, oscillation, liquid inside of the compressor etc.). The load cycle test LTT500 is carried out with variably increasing stress levels 1 … 6.
- according to the standard procedure of the Institute of Air Handling and Refrigeration over approx. 500 h or
- according to the individual demands of clients.
- Basis of comparison: compressor parameters at suitable characteristic map reference points according to DIN EN 13771-1 (refrigeration capacity, drive power, CoP, volumetric efficiency and quality grade)
Efficiency and effect of propane (and others) can be analysed using
- semi-hermetic and
- hermetic compressors (Types: reciprocating piston, eccentric piston, scroll)