Riello NXHM - Page 61

123
ENGLISH
12) Cabling
Check that cabling will not be subject to wear, corrosion, excessive pressure, vibration, sharp edges or any other adverse environmental
HႇHFWV7KHFKHFNVKDOODOVRWDNHLQWRDFFRXQWWKHHႇHFWVRIDJLQJRUFRQWLQXDOYLEUDWLRQIURPVRXUFHVVXFKDVFRPSUHVVRUVRUIDQV
 'HWHFWLRQRIÀDPPDEOHUHIULJHUDQWV
Under no circumstances shall potential sources of ignition be used in the searching for or detection of refrigerant leaks. A halide torch
 IRUDQ\RWKHUGHWHFWRUXVLQJDQDNHGÀDPHVKDOOQRWEHXVHG
14) Leak detection methods
 7KHIROORZLQJOHDNGHWHFWLRQPHWKRGVDUHGHHPHGDFFHSWDEOHIRUV\VWHPVFRQWDLQLQJÀDPPDEOHUHIULJHUDQWV(OHFWURQLFOHDNGHWHFWRUVVKDOO
EHXVHGWRGHWHFWÀDPPDEOHUHIULJHUDQWVEXWWKHVHQVLWLYLW\PD\QRWEHDGHTXDWHRUPD\QHHGUHFDOLEUDWLRQ'HWHFWLRQHTXLSPHQWVKDOO
be calibrated in a refrigerant-free area.) Ensure that the detector is not a potential source of ignition and is suitable for the refrigerant. Leak
detection equipment shall be set at a percentage of the LFL of the refrigerant and shall be calibrated to the refrigerant employed and the
DSSURSULDWHSHUFHQWDJHRIJDVPD[LPXPLVFRQ¿UPHG/HDNGHWHFWLRQÀXLGVDUHVXLWDEOHIRUXVHZLWKPRVWUHIULJHUDQWVEXWWKHXVHRI
detergents containing chlorine shall be avoided as the chlorine may react with the refrigerant and corrode the copper pipe-work. If a leak is
VXVSHFWHGDOOQDNHGÀDPHVVKDOOEHUHPRYHGRUH[WLQJXLVKHG,IDOHDNDJHRIUHIULJHUDQWLVIRXQGZKLFKUHTXLUHVEUD]LQJDOORIWKHUHIULJHU-
DQWVKDOOEHUHFRYHUHGIURPWKHV\VWHPRULVRODWHGE\PHDQVRIVKXWRႇYDOYHVLQDSDUWRIWKHV\VWHPUHPRWHIURPWKHOHDN2[\JHQIUHH
nitrogen (OFN) shall then be purged through the system both before and during the brazing process.
15) Removal and evacuation
When breaking into the refrigerant circuit to make repairs of for any other purpose conventional procedures shall be used, However, it is
LPSRUWDQWWKDWEHVWSUDFWLFHLVIROORZHGVLQFHÀDPPDELOLW\LVDFRQVLGHUDWLRQ7KHIROORZLQJSURFHGXUHVKDOOEHDGKHUHGWR
 Remove refrigerant;
 Purge the circuit with inert gas;
 Evacuate;
 Purge again with inert gas;
 Open the circuit by cutting or brazing.
  7KHUHIULJHUDQWFKDUJHVKDOOEHUHFRYHUHGLQWRWKHFRUUHFWUHFRYHU\F\OLQGHUV7KHV\VWHPVKDOOEHÀXVKHGZLWK2)1WRUHQGHUWKHXQLWVDIH
This process may need to be repeated several times.
Compressed air or oxygen shall not be used for this task.
  )OXVKLQJVKDOOEHDFKLHYHGE\EUHDNLQJWKHYDFXXPLQWKHV\VWHPZLWK2)1DQGFRQWLQXLQJWR¿OOXQWLOWKHZRUNLQJSUHVVXUHLVDFKLHYHGWKHQ
YHQWLQJWRDWPRVSKHUHDQG¿QDOO\SXOOLQJGRZQWRDYDFXXP7KLVSURFHVVVKDOOEHUHSHDWHGXQWLOQRUHIULJHUDQWLVZLWKLQWKHV\VWHP
  :KHQWKH¿QDO2)1FKDUJHLVXVHGWKHV\VWHPVKDOOEHYHQWHGGRZQWRDWPRVSKHULFSUHVVXUHWRHQDEOHZRUNWRWDNHSODFH
This operation is absolutely vital if brazing operations on the pipe-work are to take place.
Ensure that the outlet for the vacuum pump is not closed to any ignition sources and there is ventilation available. Ensure that the outlet for
the vacuum pump is not closed to any ignition sources and there is ventilation available.
16) Charging procedures
In addition to conventional charging procedures, the following requirements shall be followed:
 (QVXUHWKDWFRQWDPLQDWLRQRIGLႇHUHQWUHIULJHUDQWVGRHVQRWRFFXUZKHQXVLQJFKDUJLQJHTXLSPHQW+RVHVRUOLQHVVKDOOEHDVVKRUWDV
possible to minimize the amount of refrigerant contained in them.
 Cylinders shall be kept upright.
 Ensure that the refrigeration 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 overall the refrigeration system.
 Prior to recharging the system it shall be pressure tested with OFN. The system shall be leak tested on completion of charging
but prior to commissioning. A follow up leak test shall be carried out prior to leaving the site.
17) Deco mmissioning
Before carrying out this procedure, it is essential that the technician is completely familiar with the equipment and all its detail. It is recommended
good practice that all refrigerants are recovered safely. Prior to the task being carried out, an oil and refrigerant sample shall be taken.
In case analysis is required prior to re-use of reclaimed refrigerant. It is essential that electrical power is available before the task is commenced.
a) Become familiar with the equipment and its operation.
b) Isolate system electrically
c) Before attempting the procedure ensure that:
 Mechanical handling equipment is available, if required, for handling refrigerant cylinders.
 All personal protective equipment is available and being used correctly.
 The recovery process is supervised at all times by a competent person.
Recovery equipment and cylinders conform to the appropriate standards.
d) Pump down refrigerant system, if possible.
e) If a vacuum is not possible, make a manifold so that refrigerant can be removed from various parts of the system.
f) Make sure that cylinder is situated on the scales before recovery takes place.
g) Start the recovery machine and operate in accordance with manufacturer's instructions.
h) Do not overall cylinders. (No more than 80% volume liquid charge).
i) Do not exceed the maximum working pressure of the cylinder, even temporarily.
 M:KHQWKHF\OLQGHUVKDYHEHHQ¿OOHGFRUUHFWO\DQGWKHSURFHVVFRPSOHWHGPDNHVXUHWKDWWKHF\OLQGHUVDQGWKHHTXLSPHQWDUH
UHPRYHGIURPVLWHSURPSWO\DQGDOOLVRODWLRQYDOYHVRQWKHHTXLSPHQWDUHFORVHGRႇ
k) Recovered refrigerant shall not be charged into another refrigeration system unless it has been cleaned and checked.
18) Labelling
Equipment shall be labelled stating that it has been de-commissioned and emptied of refrigerant. The label shall be dated and signed.
(QVXUHWKDWWKHUHDUHODEHOVRQWKHHTXLSPHQWVWDWLQJWKHHTXLSPHQWFRQWDLQVÀDPPDEOHUHIULJHUDQW
19) Recovery
When removing refrigerant from a system, either for service or decommissioning, it is recommended good practice that all refrigerants
are removed safely.