Compressor Return Procedure For A2L Systems; Lubrication And Oil Removal - Emerson Copeland 4MF-13X Application Manuallines

major portion of the oil may still be in the system. While this may not affect the reliability of the
replacement compressor, the extra oil will add to rotor drag and increase power usage.

6.6.2 Compressor return procedure for A2L systems

Compressors from A1-refrigerant systems can be sent back to Emerson for diagnosis with closed
suction and discharge valves and the oil filling inside. However, the refrigerant should be removed
first. In addition, the warning sticker with the flammable symbol should be removed so that the
compressors are not misdeclared on receipt at the factory.
For all systems with A2L refrigerants, if a compressor has to be returned to the manufacturer for
analysis, the refrigerant and the oil have to be removed completely. For the shipping process, all
compressor connections must remain open and warning stickers for flammable refrigerant must be
placed on the shipping box.
▪ During the entire working procedure continuously check if the ambient atmosphere is flammable.
If a flammable atmosphere is detected, ensure proper ventilation of the working space and
immediately cut-off the power supply.
▪ Resume working after the atmosphere is no longer dangerous.
▪ Recover the refrigerant from the system using a suitable recovery unit. During this action, the
compressor crankcase heater could be energized – immediately de-energize in case a flammable
atmosphere is detected.
▪ Recover to 3 mbar absolute pressure or lower. For best results and to recover also the refrigerant
dissolved in the oil, run the recovery unit two or three times as necessary.
▪ Flush the whole system with oxygen-free dry nitrogen.
▪ Disassemble the compressor on the discharge and suction valves or with a cutting tool. Drain and
recover compressor oil properly. Purge the compressor with dry nitrogen again for a few minutes.
▪ The compressor should be returned free of oil and with connections open – do not close
connections with valves or plugs.
▪ Collect and secure the oil properly. Provide information about the quantity of oil drained from the
compressor and its colour. Ideally, send a good picture.
▪ Dispose of the oil according to local rules and regulations.
▪ Use a proper cardboard box package when preparing the compressor for shipment. Place
warning icons
the box: "Warning! Flammable A2L refrigerant compressor for analysis".
▪ The compressor must be kept in the upright position – mark the box accordingly.
▪ If more than one compressor have to be returned, each compressor must be packed individually.
NOTE: Check with the transport company that all the requirements that apply to such
shipments are complied with.
6.7

Lubrication and oil removal

WARNING
Air/A2L flammable refrigerant mixture! Flammable and explosive
atmosphere! Fire and explosion hazard! When removing oil from an A2L
refrigerant system, use suitable recovery unit and recycling bottles also for oil
disposal as A2L refrigerant may still be solved in the oil.
CAUTION
Chemical reaction! Compressor destruction! Do not mix up ester oils with
mineral oil and/or alkyl benzene.
The compressor is supplied with an initial oil charge. The standard oil charge for use with Stream
4M* & 6M* compressors is a polyolester (POE) lubricant Emkarate RL 32 3MAF. See nameplate for
original oil charge shown in litres. A field recharge is from 0.05 to 0.1 litre less. Oil recharge values
can be taken from Copeland Select software at www.climate.emerson.com/en-gb.
One disadvantage of POE is that it is far more hygroscopic than mineral oil – see Figure 38. Only
brief exposure to ambient air is needed for POE to absorb sufficient moisture to make it unacceptable
for use in a refrigeration system. Since POE holds moisture more readily than mineral oil it is more
difficult to remove it through the use of vacuum. The compressors supplied by Emerson contain oil
AGL_Stream_ST_A2L_A1_4M_6M_EN_Rev00
on each side and on the top of the box. Mention the following message on
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