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7 

CAUTION 

 

2-5. No ignition sources 

 

No person carrying out work in relation to a refrigeration 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. 

2-6. 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. 

2-7. Checks to the refrigeration 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 charge size 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. 
-       Refrigeration 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. 

2-8. 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. 

 

8 

CAUTION 

7. 

Leak detection methods 

 

Electronic leak detectors shall 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.) 

 

Ensure that the detector is not a potential source of ignition and is suitable for the refrigerant used. 

 

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. 

 

Leak detection fluids are suitable for use with most refrigerants but the use of detergents containing chlorine shall be avoided as the 
chlorine may react with the refrigerant and corrode the copper pipe-work. 

 

If a leak is suspected, all naked flames shall be removed/extinguished. 

 

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. Oxygen free nitrogen (OFN) shall then be purged through 
the system both before and during the brazing process. 

8. 

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 again 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 “flushed” with OFN to render the unit safe. 

 

This process may need to be repeated several times. 

 

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 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 ignition sources and there is ventilation available. 

9. 

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 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 over fill the refrigeration 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. 

10. 

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 
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 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 refrigeration 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. 

9 

CAUTION 

11. 

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. 

12. 

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. 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

10 

Performance Test Condition 

EUROVENT 

Power Supply 

Phase, Hz 

Single, 50 

V 230 

 Min. 

Mid. 

Max. 

Cooling 

Capacity 

kW 1.80  2.00  2.90 

BTU/h 6140 

6820 

9890 

Running Current 

A 

– 

2.70 

– 

Input Power 

W 

340 

550 

860 

Annual Consumption 

kWh 

– 

275 

– 

EER W/W 

5.29  3.64  3.37 

Indoor Noise (H / L / QLo) 

dB-A 

34 / 29 / 26 

Power Level dB 

50 / – / – 

Heating

 

Capacity 

kW 1.20  3.20  4.10 

BTU/h 4090 

10900  14000 

Running Current 

A 

– 

4.10 

– 

Input Power 

W 

300 

840 

1.33k 

COP W/W 

4.00  3.81  3.08 

Indoor Noise (H / L / QLo) 

dB-A 

36 / 29 / 26 

Power Level dB 

52 / – / – 

Indoor Fan

 

Type  

SIROCCO 

Material  

GFZ010A 

/ 

GF20 

Motor Type 

 

DC / Transistor (8-poles) 

Input Power 

W 

– 

Output Power 

W 

51 

Speed 

QLo 

Cool rpm 

800 

Heat rpm 

790 

Lo 

Cool rpm 

880 

Heat rpm 

860 

Me 

Cool rpm 

970 

Heat rpm 

960 

Hi 

Cool rpm 

1070 

Heat rpm 

1070 

SHi 

Cool rpm 

1120 

Heat rpm 

1120 

Moisture Removal 

L/h (Pt/h) 

1.3 (2.7) 

Indoor 

Airflow 

QLo 

Cool m

3

/min (ft

3

/min.) 7.3 

(260) 

Heat m

3

/min (ft

3

/min.) 7.2 

(250) 

Lo 

Cool m

3

/min (ft

3

/min.) 8.2 

(290) 

Heat m

3

/min (ft

3

/min.) 7.9 

(280) 

Me 

Cool m

3

/min (ft

3

/min.) 9.0 

(320) 

Heat m

3

/min (ft

3

/min.) 8.9 

(310) 

Hi 

Cool m

3

/min (ft

3

/min.) 10.1 

(355) 

Heat m

3

/min (ft

3

/min.) 10.1 

(355) 

SHi 

Cool m

3

/min (ft

3

/min.) 10.5 

(370) 

Heat m

3

/min (ft

3

/min.) 10.5 

(370) 

Dimension 

Height (I/D) 

mm (inch) 

200 (7-7/8) 

Width (I/D) 

mm (inch) 

750 (29-17/32) 

Depth (I/D) 

mm (inch) 

640 (25-7/32)