Carrier NDK33BN0KB, Operation & Service Manual

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62-61753-21 8-9
8.5.2 Removing The R-452A Refrigerant Charge
BEFORE USING THIS REFRIGERANT UNIT:

Read carefully all safety information explained in the safety manual and indicated on the
product.

Be sure that everybody who will use this procedure has been trained to use it in a safe way
R-452A refrigerant is an A1 non-flammable refrigerant blend which includes some mildly flammable
constituents.
As such, please follow all proper service and maintenance safety procedures:

In particular, ensure that proper evacuation procedure is strictly followed before performing any
“hot work”, including but not limited to brazing or welding, on these units to prevent flare up of
residual refrigerant.

In particular refrigerant must be reclaimed until equipment gauge indicates -20 inHG (-0.67bar/ -
9,82 Psia) of vacuum.

This specific risk has to be taken into account especially in case of work at height (fall risk).
To perform correctly this procedure and allow a correct R-452A recovery:
Please ensure that the ambient temperature around the unit is at minimum 20°C:
Before intervention makes sure the Start-Stop function is off.
Refer to the Unit operation manual.
After any operation on the unit, do not forget to put all skin back.
In case of leak on the refrigeration circuit,
Please ensure the minimum pressure is reached thanks to the recovery machine and ensure a proper
nitrogen purge while unbrazing operation.
In case of unbrazing on the evaporator side/
Store the refrigerant in the condensing unit and apply the below procedure on the evaporator side.
For environmental, health and safety concerns this procedure MUST be followed to avoid any
leaks or refrigerant blocks.
Performing “hot work” on a unit without having properly followed this procedure may lead to per-
sonal injury.
Personal protective equipment
Before doing anything on this refrigerant unit and to avoid personal injury:
ALWAYS use tools and Personal Protective Equipment in accordance with
and follow Carrier Log-out/Tag-out procedure
Hearing protection is recommended when unit is running.