Manual for Refrigeration Servicing Technicians - UNEP - Division of ...

5
Retrofitting
General retrofitting process flows
The specific procedures are:
Retrofitting stationary RAC systems 4
MVAC retrofitting procedure 4
Retrofitting stationary RAC systems
Here are the sequential steps involved in a retrofit of a CFC or HCFC based
system.
1 - Record the system performance data prior to retrofit in order to
establish the normal operating conditions for the equipment.
Data should include temperatures and pressure measurements
throughout the system, including the evaporator, compressor
suction and discharge, condenser and expansion device. These
measurements will be useful when adjusting the system during the
retrofit.
2 - Pump down the system and recover the refrigerant before opening
the refrigeration system.
3 - Recovered refrigerant must be stored only in a specified refillable
container or cylinder and properly labelled.
4 - Recovery of refrigerant shall be done using a recovery machine
or a recovery and recycling machine, operated only by a qualified
technician.
5 - Knowing the recommended CFC or HCFC charge size for the system
is helpful. If it is not known, weigh the entire amount of refrigerant
removed. This amount can be used as a guide for the initial quantity
of replacement refrigerant to be charged into the system.
6 - The technician should exert all efforts to ensure the prevention of
refrigerant emissions during the recovery operation.
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