HOMCOM 823-052V70 Manual page 15

12. Cabling:
• Check the cabling to ensure it is not exposed to conditions that could cause wear,
corrosion, excessive pressure, vibration or other environmental impacts.
• Consider the effects of ageing and continuous vibration from sources like
compressors or fans.
13. Detection of flammable refrigerants:
• Never use potential ignition sources when searching for refrigerant leaks.
• Avoid using a halide torch or any detector that involves a naked flame.
14. Removal and evacuation:
Follow standard procedures when accessing the refrigerant circuit for repairs or
other purposes.
When dealing with flammable refrigerants, adhere to best practices due to their
flammability. The following steps should be followed:
• Remove refrigerant.
• Purge the circuit with inert gas.
• Evacuate the circuit.
• Purge again with inert gas.
• Open the circuit through cutting or brazing.
Refrigerant charge should be recovered into appropriate recovery cylinders. For
appliances with flammable refrigerants, the system needs to be purged with
oxygen-free nitrogen to ensure safety.
This purging process may need to be repeated multiple times. Do not use
compressed air or oxygen for purging refrigerant systems.
For appliances with flammable refrigerants, purging should involve breaking the
vacuum in the system with oxygen-free nitrogen. Continue filling until reaching the
desired working pressure, then vent to the atmosphere and subsequently evacuate
the system to create a vacuum. Repeat this process until no refrigerant remains in
the system. Before starting any brazing operations on the pipes, the system should
be vented down to atmospheric pressure using the final charge of oxygen-free
nitrogen
Make sure the vacuum pump outlet is located away from potential ignition sources
and ensure proper ventilation is in place.
15. Charging procedures
In addition to standard charging procedures, it is important to follow these steps:
• Take precautions to prevent contamination of different refrigerants when using
charging equipment. Use short hoses or lines to minimise refrigerant volume
retained in them.
• Store cylinders in the proper position as instructed.
• Make sure the refrigerating system is properly grounded before charging it with
refrigerant.
• Label the system when charging is complete, if it hasn't been done already.
• Exercise extreme caution to avoid overfilling the refrigerating system.
Before recharging the system, perform a pressure test using the suitable purging
gas. After charging is complete but before commissioning, conduct a leak test on
the system. Also, remember to perform a final leak test before leaving the site.
16. Decommissioning
Before this procedure, the technician must know how to use the equipment
properly. Recover refrigerants safely before starting. Take oil and refrigerant
samples for analysis before reusing the recovered refrigerant. Ensure there is
electricity available before starting.
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