MAXA i-32V5 - Page 35

i-32V5 Air/water inverter heat pumps with axial fansi
35
Measure Completed Notes
11

• On no account use possible sources of ignion for refrigerant detecon or
leak detecon.
• Flame leak detectors or other detectors with open ames must not be used.
12

The following leak detecon processes are suitable for systems with ammable
refrigerants:
Leak detecon with electronic refrigerant detectors:
• Electronic refrigerant detectors may not have the required sensi- vity or
may need to be calibrated to the relevant range. Carry out the calibraon in
refrigerant-free surroundings.
• The refrigerant detector must be suitable for the R32 refriger- ant to be de-
tected.
• The refrigerant detector must not contain any potenal sources of ignion.
• Calibrate the refrigerant detector to the refrigerant used. Set the response
threshold to < 3 g/a, suitable for propane.
Leak detecon with liquid leak detectors:
• Liquid leak detectors are suitable for use with most refrigerants.
! Please note
Liquid leak detectors containing chlorine may react with
the refrigerant. This could result in corrosion.
Do not use liquid leak detectors that contain chlorine.
Measures to take if a leak in the refrigerant circuit occurs:
• Immediately exnguish all open ames in the vicinity of the heat pump.
• If brazing/soldering work needs to be undertaken to remedy the leak, al-
ways extract all the refrigerant from the refrigerant circuit. Purge the site
to be brazed/soldered before and during the braz- ing/soldering work with
oxygen-free nitrogen.
13

When breaking into the refrigerant circuit to make repairs – or for any other
purpose – convenonal procedures shall be used. However, it is important that
best pracce is followed since ammability is a consideraon. The following pro-
cedure shall be adhered to:
- remove refrigerant;
- purge the circuit with inert gas;
- evacuate;
- purge again with inert gas;
- open the circuit by cung or brazing.
The refrigerant charge shall be recovered into the correct recovery cylinders. The
system shall be “ushed” with OFN to render the unit safe. This process may
need to be repeated several mes. Compressed air or oxygen shall not be used
for this task.
Flushing shall be achieved by breaking the vacuum in the system with OFN and
connuing to ll unl the working pressure is achieved, then venng to atmo-
sphere, and nally pulling down to a vacuum. This process shall be repeated unl
no refrigerant is within the system. When the nal OFN charge is used, the sys-
tem shall be vented down to atmospheric pressure to enable work to take place.
This operaon is absolutely vital if brazing operaons on the pipe-work are to
take place.
Ensure that the outlet for the vacuum pump is not close to any ignion sources
and there is venlaon available.
14

In addion to convenonal charging procedures, the following requirements
shall be followed.
• Ensure that contaminaon of dierent 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 upright.
• Ensure that the refrigeraon 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 overll the refrigeraon system.
Before recharging, the system shall be pressure tested with OFN. The system
should be leak tested aer recharging but before commissioning. An addional
leak test must be performed before leaving the site.