General guidelines for the installation and maintenance of refrigeration systems with propane and propene
- For pipe joints, soldered and welded connections (permanently sealed to EN378-1) are preferred.
- Do not use capillary tubes, use metallic pipe joints or suitable, flexible refrigerant lines. Note: Flexible refrigerant lines must be checked for tightness, for example, according to German regulations (BGR 500), every 6 months.
- Perform soldering work only under a protective charge. Use dried nitrogen. Do not use R290 and R1270 as protective charge!
- Use heat exchangers, expansion valves, other control devices, pressure cut-outs and safety pressure cut-outs especially designed for R290 and R1270.
- For indoor installations, switch on room ventilation prior to charging refrigerant.
- Due to their low liquid density, the maximum possible refrigerant charge (relative to the weight) is much lower than with R22 or R404A.
- Max. charged amount per 1 dm3 of volume (liquid temperature 20°C, vessel volume 90%):
- R22 -> 1.09 kg // R404A -> 0.96 kg
- R290 -> 0.45 kg // R1270 -> 0.46 kg
- Immediately after commissioning, check pipelines for abnormal vibrations (danger of rupture). If required, take additional safety measures.
- When using suction side cleaning filters, change filter cartridges after approx. 100 operating hours. For disposal information, see the following section.
Maintenance work
Danger of spark formation due to unintended switching operations or overheating of the oil heater during oil change.
Prior to interventions in the refrigerant circuit, interrupt the power supply on the main switch!
Observe special regulations for storage and transport of flammable gases.
When performing maintenance work indoors, always switch on room ventilation!
Danger of spark formation, when discharging electrostatic charges!
Take measures against electrostatic charging of non-metallic components, tools, auxiliaries and clothing! For example: Wear suitable antistatic clothing, use spark-free tools. If necessary, perform additional earthing of conducting parts.
- A regular inspection of the safety devices (at least once a year) is prescribed.
- In case of repair, R290 and R1270 can be extracted and reused if the system does not contain non condensable gas and no other contamination is present. Before recharging the system, flush with dried nitrogen, install a new filter drier and evacuate
- Transferring or draining (flaring) R290/R1270 may only be performed while observing the required safety precautions. Avoid air penetration into the circuit!
- Used driers or block filter cartridges contain residual amounts of flammable R290 or R1270. Flush with nitrogen and guarantee suitable disposal.
Fire hazard!
The used oil contains a relatively large amount of dissolved refrigerant.
Pack used oil safely. Dispose of in an environmentally friendly manner.
- Hydrocarbons, for example propane, R290 or propene, R1270 and low-fluorinated flammable refrigerants, for example R1234yf, dissolve very well in refrigeration compressor oil at room temperature. This also applies to blends containing these substances.
- Used oil from such systems may still contain relatively high percentages of dissolved flammable gases even at atmospheric pressure. These components gas out.
- Observe during storage and transport:
- Fill used oil into pressure resistant vessels.
- Fill vessels with nitrogen as a protective gas and close them.
- Mark them, e. g. with the warning sign "flammable substance" W021 from ISO7010.
- In case of compressor replacement:
- Keep compressor completely sealed (close shut-off valves!).
- Extract the refrigerant.
- Charge the compressor with a protective charge (dried nitrogen) (excess pressure of 0.2 .. 0.5 bar).
- Make sure that the logo "Attention Risk of Fire" (ISO7010 W021), Marking of the propane/propene compressors is attached to the compressor readily visible.