Panasonic CS-NZ35YKE User manual

© Panasonic Corporation 2022
Order No: PAPAMY2207015CE
Indoor Unit Outdoor Unit
CS-NZ25YKE
CS-NZ35YKE
CS-NZ50YKE
CU-NZ25YKE
CU-NZ35YKE
CU-NZ50YKE
Destination
Europe
Please file and use this manual together with Wireless LAN Module Setup Instructions Order No ACXF55-3341*
WARNING
This service information is designed for experienced repair technicians only and is not designed for use by the general public.
It does not contain warnings or cautions to advise non-technical individuals of potential dangers in attempting to service a product.
Products powered by electricity should be serviced or repaired only by experienced professional technicians. Any attempt to service
or repair the products dealt with in this service information by anyone else could result in serious injury or death.
PRECAUTION OF LOW TEMPERATURE
In order to avoid frostbite, be assured of no refrigerant leakage during the installation or repairing of refrigerant circuit.
CAUTION
R32 REFRIGERANT – This Air Conditioner contains and operates with refrigerant R32.
THIS PRODUCT MUST ONLY BE INSTALLED OR SERVICED BY QUALIFIED PERSONNEL.
Refer to National, State, Territory and local legislation, regulations, codes, installation & operation manuals, before the installation,
maintenance and/or service of this product.
IMPORTANT SAFETY NOTICE
There are special components used in this equipment which are important for safety. These parts are marked by in the Schematic
Diagrams, Circuit Board Diagrams, Exploded Views and Replacement Parts List. It is essential that these critical parts should be replaced
with manufacturer’s specified parts to prevent shock, fire or other hazards. Do not modify the original design without permission of
manufacturer.

 Specifications, designs and contents in this Service Manual are subject to change without notice.
2
TABLE OF CONTENTS
PAGE PAGE
1. Safety Precautions .............................................3
2. Precaution for Using R32 Refrigerant ..............6
3. Specifications ...................................................11
4. Features.............................................................17
5. Location of Controls and Components..........18
5.1 Indoor Unit .................................................. 18
5.2 Outdoor Unit ............................................... 18
5.3 Remote Control .......................................... 18
6. Dimensions .......................................................19
6.1 Indoor Unit .................................................. 19
6.2 Outdoor Unit ............................................... 21
7. Refrigeration Cycle Diagram ...........................22
7.1 CS-NZ25YKE CU-NZ25YKE
CS-NZ35YKE CU-NZ35YKE ..................... 22
7.2 CS-NZ50YKE CU-NZ50YKE ..................... 23
8. Block Diagram ..................................................24
9. Wiring Connection Diagram ............................25
9.1 Indoor Unit .................................................. 25
9.2 Outdoor Unit ............................................... 27
10. Electronic Circuit Diagram ..............................29
10.1 Indoor Unit .................................................. 29
10.2 Outdoor Unit ............................................... 31
11. Printed Circuit Board .......................................33
11.1 Indoor Unit .................................................. 33
11.2 Outdoor Unit ............................................... 36
12. Installation Instruction.....................................37
12.1 Select the Best Location ............................. 37
12.2 Indoor Unit .................................................. 38
12.3 Outdoor Unit ............................................... 44
13. Installation and Servicing Air Conditioner
using R32 ..........................................................51
13.1 About R32 Refrigerant ................................ 51
13.2 Characteristics of R32 Refrigerant ............. 51
13.3 Refrigerant piping installation • Tools used
in services ................................................... 53
13.4 New installation, Relocation,
Repairing of Refrigerant Cycle System
The Procedures .......................................... 57
13.5 Piping installation of R32 ............................ 58
13.6 Installation, Relocation, and Service .......... 59
13.7 Repairing of refrigerant cycle /
Brazing point ............................................... 63
13.8 <Reference> Analysis method for no error
code, no cooling / no warming .................... 69
14. Operation Control.............................................71
14.1 Basic Function ............................................ 71
14.2 Indoor Fan Motor Operation ....................... 72
14.3 Outdoor Fan Motor Operation .................... 74
14.4 Airflow Direction .......................................... 75
14.5 Quiet Operation (Cooling Mode/Cooling
Area of Dry Mode) ......................................77
14.6 Quiet Operation (Heating) ..........................77
14.7 Powerful Mode Operation ...........................77
14.8 Timer Control ..............................................78
14.9 Sleep Mode Operation ...............................78
14.10 Auto Restart Control ...................................80
14.11 Indication Panel ..........................................80
14.12 +8/15°C Heat Operation .............................81
14.13 nanoe™ X Operation ...................................82
14.14 Wireless LAN Control .................................84
15. Protection Control ............................................87
15.1 Protection Control for All Operations ..........87
15.2 Protection Control for Cooling & Soft Dry
Operation ....................................................89
15.3 Protection Control for Heating Operation ...91
16. Servicing Mode .................................................92
16.1 Auto OFF/ON Button ..................................92
16.2 Heat Only Operation ...................................93
16.3 Remote Control Button ...............................94
17. Troubleshooting Guide................................. 103
17.1 Refrigeration Cycle System ..................... 103
17.2 Breakdown Self Diagnosis Function ........ 105
17.3 Error Codes Table ................................... 106
17.4 Self-diagnosis Method ............................. 108
18. Disassembly and Assembly Instructions ... 136
18.1 CS-NZ25YKE CS-NZ35YKE .................. 136
18.2 CS-NZ50YKE .......................................... 142
18.3 How to Replace Network Adaptor ........... 148
18.4 To Setup Wireless LAN Module and
Panasonic Comfort Cloud........................ 148
18.5 Outdoor Electronic Controller Removal
Procedure ................................................ 149
19. Technical Data ............................................... 151
19.1 Cool Mode Performance Data ................. 151
19.2 Heat Mode Performance Data ................. 152
20. Service Data ................................................... 153
20.1 Cool Mode Outdoor Air Temperature
Characteristic ........................................... 153
20.2 Heat Mode Outdoor Air Temperature
Characteristic ........................................... 156
20.3 Piping Length Correction Factor .............. 159
21. Exploded View and Replacement Parts
List .................................................................. 161
21.1 Indoor Unit ............................................... 161
21.2 Outdoor Unit ............................................ 167

3
1. Safety Precautions
 Read the following “SAFETY PRECAUTIONS” carefully before perform any servicing.
 Confirm the type of gas used before installation.
 Electrical work must be installed or serviced by a licensed electrician. Be sure to use the correct rating of the
power plug and main circuit for the model to be installed.
 The caution items stated here must be followed because these important contents are related to safety. The
meaning of each indication used is as below. Incorrect installation or servicing due to ignoring of the instruction
will cause harm or damage, and the seriousness is classified by the following indications.
WARNING This indication shows the possibility of causing death or serious injury.
CAUTION This indication shows the possibility of causing injury or damage to properties only.
 The items to be followed are classified by the symbols:
 Explanation of symbols displayed on the indoor unit or outdoor unit.
WARNING This symbol shows that this equipment uses a flammable refrigerant.
If the refrigerant is leaked, together with an external ignition source, there is a possibility of ignition.
CAUTION This symbol shows that the Installation Manual should be read carefully.
CAUTION This symbol shows that a service personnel should be handling this equipment with reference to the
Installation Manual.
CAUTION This symbol shows that there is information included in the Operation Manual and/or Installation Manual.
 Carry out test run to confirm that no abnormality occurs after the servicing. Then, explain to user the operation,
care and maintenance as stated in instructions. Please remind the customer to keep the operating instructions for
future reference.
WARNING
1. Do not use means to accelerate the defrosting process or to clean, other than those recommended by the manufacturer. Any
unfit method or using incompatible material may cause product damage, burst and serious injury.
2. Do not install outdoor unit near handrail of veranda. When installing air-conditioner unit on veranda of a high rise building, child
may climb up to outdoor unit and cross over the handrail causing an accident.
3.
Do not use unspecified cord, modified cord, joint cord or extension cord for power supply cord. Do not share the single outlet
with other electrical appliances.
Poor contact, poor insulation or over current will cause electrical shock or fire.
4. Do not tie up the power supply cord into a bundle by band. Abnormal temperature rise on power supply cord may happen.
5. Do not insert your fingers or other objects into the unit, high speed rotating fan may cause injury.
6. Do not sit or step on the unit, you may fall down accidentally.
7. Keep plastic bag (packaging material) away from small children, it may cling to nose and mouth and prevent breathing.
8.
When installing or relocating air conditioner, do not let any substance other than the specified refrigerant, eg. air etc mix into
refrigeration cycle (piping).
Mixing of air etc. will cause abnormal high pressure in refrigeration cycle and result in explosion, injury etc.
9.
Do not pierce or burn as the appliance is pressurized. Do not expose the appliance to heat, flame, sparks, or other sources of
ignition.
Else, it may explode and cause injury or death.
10. Do not add or replace refrigerant other than specified type. It may cause product damage, burst and injury etc.
This symbol denotes item that is PROHIBITTED from doing.

4
WARNING
11.
 For R32/R410A model, use piping, flare nut and tools which is specified for R32/R410A refrigerant. Using of existing (R22) piping,
flare nut and tools may cause abnormally high pressure in the refrigerant cycle (piping), and possibly result in explosion and injury.
For R32 and R410A, the same flare nut on the outdoor unit side and pipe can be used.
 Since the working pressure for R32/R410A is higher than that of refrigerant R22 model, replacing conventional piping and flare nuts
on the outdoor unit side are recommended.
 If reuse piping is unavoidable, refer to instruction “IN CASE OF REUSING EXISTING REFRIGERANT PIPING”
 Thickness for copper pipes used with R32/R410A must be more than 0.8 mm. Never use copper pipes thinner than 0.8 mm.
 It is desirable that the amount of residual oil less than 40 mg/10 m.
12. Engage authorized dealer or specialist for installation and servicing. If installation or servicing done by the user is defective, it will cause
water leakage, electrical shock or fire.
13. For refrigeration system work, Install according to this installation instructions strictly. If installation is defective, it will cause water
leakage, electrical shock or fire.
14. Use the attached accessories parts and specified parts for installation and servicing. Otherwise, it will cause the set to fall, water
leakage, fire or electrical shock.
15. Install at a strong and firm location which is able to withstand weight of the set. If the strength is not enough or installation is not properly
done, the set will drop and cause injury.
16. For electrical work, follow the national regulation, legistration and this installation instructions. An independent circuit and single outlet
must be used. If electrical circuit capacity is not enough or defect found in the electrical work, it will cause electrical shock or fire.
17.
Do not use joint cable for indoor/outdoor connection cable. Use the specified indoor/outdoor connection cable, refer to instruction
CONNECT THE CABLE TO THE INDOOR UNIT and connect tightly for indoor/outdoor connection. Clamp the cable so that no external
force will have impact on the terminal.
If connection or fixing is not perfect, it will cause heat up or fire at the connection.
18. Wire routing must be properly arranged so that control board cover is fixed properly. If control board cover is not fixed perfectly, it will
cause heat-up or fire at connection point of terminal, fire or electrical shock.
19.
This equipment is strongly recommended to be installed with Earth Leakage Circuit Breaker (ELCB) or Residual Current Device (RCD),
with sensitivity of 30 mA at 0.1 sec or less. Otherwise, it may cause electrical shock and fire in case of equipment breakdown or
insulation breakdown.
20.
During installation, install the refrigerant piping properly before running the compressor. Operation of compressor without fixing
refrigeration piping and valves at opened position will cause suck-in of air, abnormal high pressure in refrigeration cycle and result in
explosion, injury etc.
21.
During pump down operation, stop the compressor before removing the refrigeration piping. Removal of refrigeration piping while
compressor is operating and valves are opened will cause suck-in of air, abnormal high pressure in refrigeration cycle and result in
explosion, injury etc.
22. Tighten the flare nut with torque wrench according to specified method. If the flare nut is over-tightened, after a long period, the flare
may break and cause refrigerant gas leakage.
23. After completion of installation or service, confirm there is no leakage of refrigerant gas. It may generate toxic gas when the refrigerant
contacts with fire.
24. Ventilate if there is refrigerant gas leakage during operation. It may cause toxic gas when the refrigerant contacts with fire.
25. Be aware that refrigerants may not contain an odour.
26. This equipment must be properly earthed. Earth line must not be connected to gas pipe, water pipe, earth of lightning rod and
telephone. Otherwise, it may cause electrical shock in case of equipment breakdown or insulation breakdown.
27. Do not modify the machine, part, material during repairing service.
28. If wiring unit is supplied as repairing part, do not repair or connect the wire even only partial wire break. Exchange the whole wiring unit.
29. Do not wrench the fasten terminal. Pull it out or insert it straightly.
30. Must not use other parts except original parts describe in catalog and manual.
CAUTION
1. Do not install the unit in a place where leakage of flammable gas may occur. In case gas leaks and accumulates at surrounding
of the unit, it may cause fire.
2. Prevent liquid or vapor from entering sumps or sewers since vapor is heavier than air and may form suffocating atmospheres.
3. Do not release refrigerant during piping work for installation, servicing, reinstallation and during repairing a refrigerant parts.
Take care of the liquid refrigerant, it may cause frostbite.
4. Do not install this appliance in a laundry room or other location where water may drip from the ceiling, etc.

5
CAUTION
5. Do not touch the sharp aluminium fin, sharp parts may cause injury.
6. Carry out drainage piping as mentioned in installation instructions. If drainage is not perfect, water may enter the room and damage the
furniture.
7.
Select an installation location which is easy for maintenance.
Incorrect installation, service or repair of this air conditioner may increase the risk of rupture and this may result in loss damage or injury
and/or property.
8.
Power supply connection to the room air conditioner.
Use power supply cord 3 x 1.5 mm2 (1.0 ~ 1.5HP), 3 x 2.5 mm2 (2.0HP) type designation 60245 IEC 57 or heavier cord.
Connect the power supply cord of the air conditioner to the mains using one of the following method.
Power supply point should be in easily accessible place for power disconnection in case of emergency.
In some countries, permanent connection of this air conditioner to the power supply is prohibited.
1) Power supply connection to the receptacle using power plug.
Use an approved 15/16 A (1.0 ~ 1.5HP), 16 A (2.0HP), power plug with earth pin for the connection to the socket.
2) Power supply connection to a circuit breaker for the permanent connection.
Use an approved 16 A (1.0 ~ 2.0HP), circuit breaker for the permanent connection. It must be a double pole switch with a minimum
3.0 mm contact gap.
9. Installation or servicing work: It may need two people to carry out the installation or servicing work.
10. Keep any required ventilation openings clear of obstruction.
11.
Pb free solder has a higher melting point than standard solder; typically the melting point is 50°F – 70°F (30°C – 40°C) higher.
Please use a high temperature solder iron. In case of the soldering iron with temperature control, please set it to 700 ± 20°F
(370 ± 10°C).
Pb free solder will tend to splash when heated too high (about 1100°F / 600°C).
12.
Do not touch the sharp aluminum fins or edges of metal parts.
If you are required to handle sharp parts during installation or servicing, please wear hand glove.
Sharp parts may cause injury.
13. Tighten the flare nut with torque wrench according to specified method. If the flare nut is over-tightened, after a long period, the flare may
break and cause refrigerant gas leakage.
14. Do not touch outdoor unit air inlet and aluminium fin. It may cause injury.

6
2. Precaution for Using R32 Refrigerant
 Pay careful attention to the following precaution points and the installation work procedures.
WARNING
1.
When connecting flare at indoor side, make sure that the flare connection is used only once, if torqued up and released, the flare must
be remade. Once the flare connection was torqued up correctly and leak test was made, thoroughly clean and dry the surface to remove
oil, dirt and grease by following instructions of silicone sealant. Apply neutral cure (Alkoxy type) & ammonia-free silicone sealant that is
non-corrosive to copper & brass to the external of the flared connection to prevent the ingress on both the gas & liquid sides. (Moisture
may cause freezing and premature failure of the connection)
2.
The appliance shall be stored, installed and operated in a well ventilated room with indoor floor area larger than Amin (m2) [refer Table A]
and without any continuously operating ignition source. Keep away from open flames, any operating gas appliances or any operating
electric heater. Else, it may explode and cause injury or death.
3.
The mixing of different refrigerants within a system is prohibited. Models that use refrigerant R32 and R410A have a different charging
port thread diameter to prevent erroneous charging with refrigerant R22 and for safety.
Therefore, check beforehand. [The charging port thread diameter for R32 and R410A is 12.7 mm (1/2 inch).]
4. Ensure that foreign matter (oil, water, etc.) does not enter the piping.
Also, when storing the piping, securely seal the opening by pinching, taping, etc. (Handling of R32 is similar to R410A.)
5.
Operation, maintenance, repairing and refrigerant recovery should be carried out by trained and certified personnel in the use of
flammable refrigerants and as recommended by the manufacturer. Any personnel
conducting an operation, servicing or maintenance on a system or associated parts of the equipment should be trained and certified.
6. Any part of refrigerating circuit (evaporators, air coolers, AHU, condensers or liquid receivers) or piping should not be located in the
proximity of heat sources, open flames, operating gas appliance or an operating electric heater.
7. The user/owner or their authorized representative shall regularly check the alarms, mechanical ventilation and detectors, at least once a
year, where as required by national regulations, to ensure their correct functioning.
8. A logbook shall be maintained. The results of these checks shall be recorded in the logbook.
9. In case of ventilations in occupied spaces shall be checked to confirm no obstruction.
10.
Before a new refrigerating system is put into service, the person responsible for placing the system in operation should ensure that
trained and certified operating personnel are instructed on the basis of the instruction manual about the construction, supervision,
operation and maintenance of the refrigerating system, as well as the safety measures to be observed, and the properties and handling
of the refrigerant used.
11.
The general requirement of trained and certified personnel are indicated as below:
a) Knowledge of legislation, regulations and standards relating to flammable refrigerants; and,
b) Detailed knowledge of and skills in handling flammable refrigerants, personal protective equipment, refrigerant leakage prevention,
handling of cylinders, charging, leak detection, recovery and disposal; and,
c) Able to understand and to apply in practice the requirements in the national legislation, regulations and Standards; and,
d) Continuously undergo regular and further training to maintain this expertise.
12. Air-conditioner piping in the occupied space shall be installed in such a way to protect against accidental damage in operation and
service.
13. Precautions shall be taken to avoid excessive vibration or pulsation to refrigerating piping.
14. Ensure protection devices, refrigerating piping and fittings are well protected against adverse environmental effects (such as the danger
of water collecting and freezing in relief pipes or the accumulation of dirt and debris).
15. Expansion and contraction of long runs piping in refrigerating systems shall be designed and installed securely (mounted and guarded)
to minimize the likelihood hydraulic shock damaging the system.
16. Protect the refrigerating system from accidental rupture due to moving furniture or reconstruction activities.
17.
To ensure no leaking, field-made refrigerant joints indoors shall be tightness tested. The test method shall have a sensitivity of 5 grams
per year of refrigerant or better under a pressure of at least 0,25 times the maximum allowable pressure (>1.04MPa, max 4.15MPa). No
leak shall be detected.

7
CAUTION
1.
General
 Must ensure the installation of pipe-work shall be kept to a minimum. Avoid use dented pipe and do not allow acute bending.
 Must ensure that pipe-work shall be protected from physical damage.
 Must comply with national gas regulations, state municipal rules and legislation. Notify relevant authorities in accordance with all
applicable regulations.
 Must ensure mechanical connections be accessible for maintenance purposes.
 In cases that require mechanical ventilation, ventilation openings shall be kept clear of obstruction.
 When disposal of the product, do follow to the precautions in #11 and comply with national regulations.
 In case of field charge, the effect on refrigerant charge caused by the different pipe length has to be quantified, measured and
labelled.
Always contact to local municipal offices for proper handling.
 Ensure the actual refrigerant charge is in accordance with the room size within which the refrigerant containing parts are installed.
 Ensure refrigerant charge not to leak.
 Wear appropriate protective equipment, including respiratory protection, as conditions warrant.
 Keep all sources of ignition and hot metal surfaces away.
2.
Servicing
2-1. Qualification of workers
 Any qualified person who is involved with working on or breaking into a refrigerant circuit should hold a current valid certificate from
an industry-accredited assessment authority, which authorizes their competence to handle refrigerants safely in accordance with an
industry recognized assessment specification.
 Servicing shall only be performed as recommended by the equipment manufacturer. Maintenance and repair requiring the
assistance of other skilled personnel shall be carried out under the supervision of the person competent in the use of flammable
refrigerants.
 Servicing shall be performed only as recommended by the manufacturer.
 The system is inspected, regularly supervised and maintained by a trained and certified service personnel who is employed by the
person user or party responsible.
2-2. Checks to the area
 Prior to beginning work on systems containing flammable refrigerants, safety checks are necessary to ensure that the risk of
ignition is minimised.
For repair to the refrigerating system, the precautions in #2-3 to #2-7 must be followed before conducting work on the system.
2-3. Work procedure
 Work shall be undertaken under a controlled procedure so as to minimize the risk of a flammable gas or vapour being present while
the work is being performed.
2-4. General work area
 All maintenance staff and others working in the local area shall be instructed and supervised on the nature of work being carried
out.
 Avoid working in confined spaces. Always ensure away from source, at least 2 meter of safety distance, or zoning of free space
area of at least 2 meter in radius.
2-5. Checking for presence of refrigerant
 The area shall be checked with an appropriate refrigerant detector prior to and during work, to ensure the technician is aware of
potentially flammable atmospheres.
 Ensure that the leak detection equipment being used is suitable for use with flammable refrigerants, i.e. non sparking, adequately
sealed or intrinsically safe.
 In case of leakage/spillage happened, immediately ventilate area and stay upwind and away from spill/release.
 In case of leakage/spillage happened, do notify persons down wind of the leaking/spill, isolate immediate hazard area and keep
unauthorized personnel out.
2-6. Presence of fire extinguisher
 If any hot work is to be conducted on the refrigerating equipment or any associated parts, appropriate fire extinguishing equipment
shall be available at hand.
 Have a dry powder or CO2 fire extinguisher adjacent to the charging area.
2-7. No ignition sources
 No person carrying out work in relation to a refrigerating system which involves exposing any pipe work that contains or has
contained flammable refrigerant shall use any sources of ignition in such a manner that it may lead to the risk of fire or explosion.
He/She must not be smoking when carrying out such work.
 All possible ignition sources, including cigarette smoking, should be kept sufficiently far away from the site of installation, repairing,
removing and disposal, during which flammable refrigerant can possibly be released to the surrounding space.
 Prior to work taking place, the area around the equipment is to be surveyed to make sure that there are no flammable hazards or
ignition risks.
 “No Smoking” signs shall be displayed.
2-8. Ventilated area
 Ensure that the area is in the open or that it is adequately ventilated before breaking into the system or conducting any hot work.
 A degree of ventilation shall continue during the period that the work is carried out.
 The ventilation should safely disperse any released refrigerant and preferably expel it externally into the atmosphere.
2-9. Checks to the refrigerating equipment
 Where electrical components are being changed, they shall be fit for the purpose and to the correct specification.
 At all times the manufacturer’s maintenance and service guidelines shall be followed.
 If in doubt consult the manufacturer’s technical department for assistance.
 The following checks shall be applied to installations using flammable refrigerants.
- The actual refrigerant charge is in accordance with the room size within which the refrigerant containing parts are installed.
- The ventilation machinery and outlets are operating adequately and are not obstructed.
- If an indirect refrigerating circuit is being used, the secondary circuit shall be checked for the presence of refrigerant.
- Marking to the equipment continues to be visible and legible. Markings and signs that are illegible shall be corrected.
- Refrigerating pipe or components are installed in a position where they are unlikely to be exposed to any substance which
may corrode refrigerant containing components, unless the components are constructed of materials which are inherently
resistant to being corroded or are properly protected against being so corroded.

8
CAUTION
2.
2-10. Checks to electrical devices
 Repair and maintenance to electrical components shall include initial safety checks and component inspection procedures.
 Initial safety checks shall include but not limit to:-
- That capacitors are discharged: this shall be done in a safe manner to avoid possibility of sparking.
- That there is no live electrical components and wiring are exposed while charging, recovering or purging the system.
- That there is continuity of earth bonding.
 At all times the manufacturer’s maintenance and service guidelines shall be followed.
 If in doubt consult the manufacturer’s technical department for assistance.
 If a fault exists that could compromise safety, then no electrical supply shall be connected to the circuit until it is satisfactorily dealt
with.
 If the fault cannot be corrected immediately but it is necessary to continue operation, an adequate temporary solution shall be used.
 The owner of the equipment must be informed or reported so all parties are advised thereinafter.
3.
Repairs to sealed components
 During repairs to sealed components, all electrical supplies shall be disconnected from the equipment being worked upon prior to
any removal of sealed covers, etc.
 If it is absolutely necessary to have an electrical supply to equipment during servicing, then a permanently operating form of leak
detection shall be located at the most critical point to warn of a potentially hazardous situation.
 Particular attention shall be paid to the following to ensure that by working on electrical components, the casing is not altered in
such a way that the level of protection is affected. This shall include damage to cables, excessive number of connections, terminals
not made to original specification, damage to seals, incorrect fitting of glands, etc.
 Ensure that apparatus is mounted securely.
 Ensure that seals or sealing materials have not degraded such that they no longer serve the purpose of preventing the ingress of
flammable atmospheres.
 Replacement parts shall be in accordance with the manufacturer’s specifications.
NOTE: The use of silicon sealant may inhibit the effectiveness of some types of leak detection equipment.
Intrinsically safe components do not have to be isolated prior to working on them.
4.
Repair to intrinsically safe components
 Do not apply any permanent inductive or capacitance loads to the circuit without ensuring that this will not exceed the permissible
voltage and current permitted for the equipment in use.
 Intrinsically safe components are the only types that can be worked on while live in the presence of a flammable atmosphere.
 The test apparatus shall be at the correct rating.
 Replace components only with parts specified by the manufacturer. Unspecified parts by manufacturer may result ignition of
refrigerant in the atmosphere from a leak.
5.
Cabling
 Check that cabling will not be subject to wear, corrosion, excessive pressure, vibration, sharp edges or any other adverse
environmental effects.
 The check shall also take into account the effects of aging or continual vibration from sources such as compressors or fans.
6.
Detection of flammable refrigerants
 Under no circumstances shall potential sources of ignition be used in the searching or detection of refrigerant leaks.
 A halide torch (or any other detector using a naked flame) shall not be used.
 The following leak detection methods are deemed acceptable for all refrigerant systems.
o No leaks shall be detected when using detection equipment with a sensitivity of 5 grams per year of refrigerant or better under
a pressure of at least 0,25 times the maximum allowable pressure (>1.04MPa, max 4.15MPa) for example, a universal sniffer.
o Electronic leak detectors may be used to detect flammable refrigerants, but the sensitivity may not be adequate, or may need
re-calibration.
(Detection equipment shall be calibrated in a refrigerant-free area.)
o Ensure that the detector is not a potential source of ignition and is suitable for the refrigerant used.
o 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 appropriate percentage of gas (25 % maximum) is confirmed.
o Leak detection fluids are also suitable for use with most refrigerants, for example, bubble method and fluorescent method
agents. The use of detergents containing chlorine shall be avoided as the chlorine may react with the refrigerant and corrode
the copper pipe-work.
o If a leak is suspected, all naked flames shall be removed/extinguished.
o If a leakage of refrigerant is found which requires brazing, all of the refrigerant shall be recovered from the system, or isolated
(by means of shut off valves) in a part of the system remote from the leak. The precautions in #7 must be followed to remove
the refrigerant.

9
CAUTION
7.
Removal and evacuation
 When breaking into the refrigerant circuit to make repairs – or for any other purpose – conventional procedures shall be used.
However, it is important that best practice is followed since flammability is a consideration.
The following procedure shall be adhered to:
• remove refrigerant -> • purge the circuit with inert gas -> • evacuate -> • purge with inert gas ->
• open the circuit by cutting or brazing
 The refrigerant charge shall be recovered into the correct recovery cylinders.
 The system shall be purged with OFN to render the appliance safe. (remark: OFN = oxygen free nitrogen, type of inert gas)
 This process may need to be repeated several times.
 Compressed air or oxygen shall not be used for this task.
 Purging shall be achieved by breaking the vacuum in the system with OFN and continuing to fill until the working pressure is
achieved, then venting to atmosphere, and finally pulling down to a vacuum.
 This process shall be repeated until no refrigerant is within the system.
 When the final OFN charge is used, the system shall be vented down to atmospheric pressure to enable work to take place.
 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 close to any potential ignition sources and there is ventilation available.
8.
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 minimize the amount of refrigerant contained in them.
- Cylinders shall be kept in an appropriate position according 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 over fill the refrigerating system.
 Prior to recharging the system it shall be pressure tested with OFN (refer to #7).
 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.
 Electrostatic charge may accumulate and create a hazardous condition when charging and discharging the refrigerant.
To avoid fire or explosion, dissipate static electricity during transfer by grounding and bonding containers and equipment before
charging/discharging.
9.
Decommissioning
 Before carrying out this procedure, it is essential that the technician is completely familiar with the equipment and all its details.
 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
recovered 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 instructions.
h) Do not over fill cylinders. (No more than 80 % volume liquid charge).
i) Do not exceed the maximum working pressure of the cylinder, even temporarily.
j) When the cylinders have been filled correctly and the process completed, make sure that the cylinders and the
equipment are removed from site promptly and all isolation valves on the equipment are closed off.
k) Recovered refrigerant shall not be charged into another refrigerating system unless it has been cleaned and checked.
 Electrostatic charge may accumulate and create a hazardous condition when charging or discharging the refrigerant.
To avoid fire or explosion, dissipate static electricity during transfer by grounding and bonding containers and equipment before
charging/discharging.
10.
Labelling
 Equipment shall be labelled stating that it has been de-commissioned and emptied of refrigerant.
 The label shall be dated and signed.
 Ensure that there are labels on the equipment stating the equipment contains flammable refrigerant.

10
CAUTION
11.
Recovery
 When removing refrigerant from a system, either for servicing or decommissioning, it is recommended good practice that all
refrigerants are removed safely.
 When transferring refrigerant into cylinders, ensure that only appropriate refrigerant recovery cylinders are employed.
 Ensure that the correct number of cylinders for holding the total system charge are available.
 All cylinders to be used are designated for the recovered refrigerant and labelled for that refrigerant (i.e. special cylinders for the
recovery of refrigerant).
 Cylinders shall be complete with pressure relief valve and associated shut-off valves in good working order.
 Recovery cylinders are evacuated and, if possible, cooled before recovery occurs.
 The recovery equipment shall be in good working order with a set of instructions concerning the equipment that is at hand and shall
be suitable for the recovery of flammable refrigerants.
 In addition, a set of calibrated weighing scales shall be available and in good working order.
 Hoses shall be complete with leak-free disconnect couplings and in good condition.
 Before using the recovery machine, check that it is in satisfactory working order, has been properly maintained and that any
associated electrical components are sealed to prevent ignition in the event of a refrigerant release.
Consult manufacturer if in doubt.
 The recovered refrigerant shall be returned to the refrigerant supplier in the correct recovery cylinder, and the relevant Waste
Transfer Note arranged.
 Do not mix refrigerants in recovery units and especially not in cylinders.
 If compressors or compressor oils are to be removed, ensure that they have been evacuated to an acceptable level to make certain
that flammable refrigerant does not remain within the lubricant.
 The evacuation process shall be carried out prior to returning the compressor to the suppliers.
 Only electric heating to the compressor body shall be employed to accelerate this process.
 When oil is drained from a system, it shall be carried out safely.