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10-15 TON HYDRONIC HEAT PUMP INSTALLATION GUIDE
Refrigerant Removal and Evacuation
When breaking into the refrigerant circuit to make repairs – or
for any other purpose conventional procedures shall be used.
However, for flammable refrigerants it is important that best
practice be followed, since flammability is a consideration.
The following procedure shall be adhered to:
• safely remove refrigerant following local and
national regulations;
• evacuate;
• purge the circuit with inert gas (optional for A2L);
• evacuate (optional for A2L);
• continuously flush or purge with inert gas when
using flame to open circuit; and
• open the circuit.
The refrigerant charge shall be recovered into the correct re-
covery cylinders if venting is not allowed by local and national
codes. For appliances containing flammable refrigerants, the
system shall be purged with oxygen-free nitrogen to render
the appliance safe for flammable refrigerants.
Charging procedures
In addition to conventional charging procedures, the following
requirements shall be followed.
• Ensure that contamination of different refrigerants does
not occur when using charging equipment.
• Hoses or lines shall be as short as possible to minimise
the amount of refrigerant contained in them.
• Cylinders shall be kept in an appropriate position ac-
cording to the instructions.
• Ensure that the REFRIGERATING SYSTEM is earthed
prior to charging the system with refrigerant.
• Label the system when charging is complete (if not
already).
• Extreme care shall be taken not to overfill the REFRIG-
ERATING SYSTEM.
Prior to recharging the system, it shall be pressure-tested with
the appropriate purging gas. The system shall be leak-tested
on completion of charging but prior to commissioning. A fol-
low up leak test shall be carried out prior to leaving the site.
This process might need to be repeated several times. Com-
pressed air or oxygen shall not be used for purging refriger-
ant systems. For appliances containing flammable refriger-
ants, refrigerants purging shall be achieved by breaking the
vacuum in the system with oxygen-free nitrogen and continu-
ing to fill until the working pressure is achieved, then venting
to atmosphere, and finally pulling down to a vacuum (optional
for A2L). This process shall be repeated until no refrigerant is
within the system (optional for A2L). When the final oxygen-
free nitrogen charge is used, the system shall be vented down
to atmospheric pressure to enable work to take place. The
outlet for the vacuum pump shall not be close to any poten-
tial ignition sources, and ventilation shall be available.
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