Preparation And Work Procedure; Disassembling System Components; Replacing A Compressor; Compressor Replacement - Emerson Copeland YB45K1E Application Manuallines

6.2

Preparation and work procedure

A work procedure shall be provided in the preparation stage. All maintenance personnel and others
working at the site shall be instructed on the nature of the work being carried out.
If any work is to be conducted on the refrigeration systems or any associated parts, appropriate fire
extinguishing equipment shall be provided. Dry powder or CO
appropriate. Confirm that appropriate fire extinguishing equipment is available near the work area.
Prior to starting to work on systems containing flammable refrigerants, safety checks are necessary
to ensure that the risk of ignition is minimized.
Work shall be undertaken under a controlled procedure so as to minimize the risk of flammable gas
or vapour being present while the work is being performed.
Avoid working on systems filled with flammable refrigerant in a confined space.
6.3

Disassembling system components

When disassembling system components please follow the main steps described hereunder:
1. For A1 refrigerant systems (R404A, R407A, R407F, R448A, R449A, R407C, R513A, R134a and
R450A), recover refrigerant and evacuate system using a recovery unit and vacuum pump. All
the refrigerant shall be recovered to avoid significant release.
2. For A2L refrigerant systems (R454C, R455A, R454A and R1234yf), recover refrigerant and
evacuate system using an A2L-dedicated recovery unit and vacuum pump. Ensure that the outlet
of the vacuum pump is not close to any potential ignition source and that ventilation is available.
3. Flush system with inert gas (dry nitrogen). Compressed air or oxygen shall not be used for purging
refrigerant systems.
4. Disassemble components with a cutting tool.
5. Drain, recover and dispose of compressor oil as appropriate.
Figure 17: Tube connecting areas
To reconnect:
▪ Recommended brazing material: Silfos with minimum 5 % silver or silver braze used on other
compressors.
▪ Due to the different thermal properties of steel and copper, brazing procedures may have to be
changed from those commonly used.
NOTE: Since the discharge stub contains a check valve, care must be taken not to overheat
it to prevent brazing material from flowing into it.
6.4

Replacing a compressor

CAUTION
Inadequate lubrication! Bearing destruction! For systems with a refrigerant
accumulator, exchange the accumulator after replacing a compressor with a
burned-out motor. The accumulator oil return orifice or screen may be plugged
with debris or may become plugged. This will result in starvation of oil to the
new compressor and a second failure.
Remove refrigerant and oil completely from the replaced compressor.

6.4.1 Compressor replacement

In the case of an A2L-refrigerant compressor replacement, the oil has to be drained out of the
compressor and the compressor should be flushed with dry nitrogen. DO NOT close the stubs with
plugs.
AGL_Ref_ST_YBK1E_EN_Rev03
To disconnect:
▪
Using a pipe cutting tool, cut off the suction and discharge
lines in such a manner that the new compressor can easily be
re-connected into the system.
▪
Heat joint areas 2 and 3 slowly and uniformly until the braze
material softens and the tube end can be pulled out from the
fitting.
fire extinguishers are considered
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