Danfoss Praktiske tips Service guide

Fitters notes Practical tips

Page

This chapter is devided into two sections:

Installation requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127

The installation process. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133

Practical tips

Fitters notes Practical tips - installation requirements

Contents Page

Installation requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129

Tubing must be kept clean . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129

Particularly damaging impurities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129

Problems caused by moisture in the system. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129

Problems caused by atmospheric air. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130

Problems caused by oil and refrigerant breakdown . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130

Problems caused by other impurities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130

Component and material requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130

Components. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130

Impurities and moisture. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131

Copper tubing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131

Refrigerant requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131

Compressor oil requirements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132

Practical tips

Notes

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Fitters notes Practical tips - installation requirements

Installation requirements

Tubing must be kept clean

More and more commercial refrigeration systems and air conditioning plants of a similar size are built up around hermetic and semihermetic compressors. These compressors, as compared to the open type, are normally more vulnerable to impurities in the refrigerant system and to incorrect operating conditions.

Therefore, in modern refrigeration systems, there are special demands on the quality of installation work and commissioning.

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A well-dimensioned, correctly installed and correctly commissioned refrigerant system is fundamental to a reliable refrigeration system with a long operating life. An absolute requirement on the refrigerant system is that it shall remain completely free of foreign bodies (impurities). Installation work must therefore be performed with a high degree of cleanliness. This applies especially to systems containing the new refrigerants.

Particularly damaging impurities

Problems caused by moisture in the system

Moisture Atmospheric air Soldering ux Rust, copper oxide, scale Metal swarf Unstable oils Certain uorinated solutions (e.g. R11

or carbon tetrachloride) Dirt or dust of any description.

Water separation and ice formation (blockage) in the expansion valve

Acid formation Ageing and breakdown of the oil Corrosion Copper precipitation (dissolved copper

from tubing deposited on bright steel parts in the compressor)

Damage to the insulating lacquer on motor windings.

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Practical tips

Fitters notes Practical tips - installation requirements

Problems caused by atmospheric air

Problems caused by oil and refrigerant breakdown

Aeration Chemical reaction between refrigerant

and oil Increased condensing pressure.

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Formation of organic and inorganic acids Corrosion Poor lubrication Abnormal wear Oil discolouration (darkening) Sludge formation Leaking discharge valves because of

oil carbon deposits Increased discharge gas temperature Compressor damage Motor burnout

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Problems caused by other impurities

Component and material requirements

Components

The other impurities mentioned can cause:

Accelerated chemical processes (breakdown)

Mechanical or electrical faults

High temperature accelerates the breakdown processes, therefore abnormally high condensing temperatures and, especially, abnormally high discharge pipe temperatures must be avoided.

For the reasons just mentioned, a number of requirements must be met. Some of these are described in the next chapter.

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Compressors for refrigeration and heat pump systems are put through a comprehensive cleaning process by the manufacturer so that, practically speaking, all traces of moisture and other impurities are removed.

All other components in the system should be of the same standard.

All components must full cleanliness requirements. In cases of doubt, components should be checked.

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Fitters notes Practical tips - installation requirements

Impurities and moisture

Impurities that might appear if component manufacturers are less thorough than they should be:

Rust and scale (loose or embedded) Old oil Flux Metal swarf Moisture

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Moisture in smaller quantities in components can be removed by simultaneous heating and blowing through with dry nitrogen (N2).

It is almost pointless to try removing other impurities. Components containing such impurities should not be used in systems with halogenous refrigerants.

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Copper tubing

Refrigerant requirements

Special copper tubing must be used for refrigerant systems, tubing that is completely clean and dry. In addition, the ends of tubes must be hermetically sealed.

Tubing other than the type just described must not be used in refrigerant systems, unless it fulls the same cleanliness requirements.

All components must remain tightly sealed until the moment they are installed in the system.

Refrigerants should only be purchased from accredited distributors. Refrigerants for hermetic systems must not contain more than:

10 ppm = 0.001% water 100 ppm = 0.01% high-boiling refrigerant 0 ppm = 0% acid 15000 ppm = 1.5% non-condensable

gases Care must therefore be exercised when using regenerated refrigerant.

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Practical tips

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Fitters notes Practical tips - installation requirements

Compressor oil requirements

Compressor oil must be approved by the compressor manufacturer and must not contain more than 25 ppm (0.0025%) water and 0% acid.

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Fitters notes Practical Tips - The installation process

Contents Page

Installation process . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135

Planning. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135

Location of main components. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135

Installation of refrigeration system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135

Piping installation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136

Location of other components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136

Compressors in parallel installation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137

Important installation processes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137

Component storage. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137

Pipe cutting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 138

Pipe cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 138

Silver soldering (brazing). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 138

Phosphor solder . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139

Use of inert gas when soldering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139

Economic soldering. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139

Be careful with the temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140

Flare connections (copper piping) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140

Evacuation, ushing and charging. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140

Necessary equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140

Vacuum pump. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141

Vacuum hoses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141

First evacuation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142

System vacuum test. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142

Flushing and provisional leak testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142

Second evacuation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142

Provisional setting of safety equipment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143

Checking the electrics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143

Refrigerant charging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143

Condensing pressure too high . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144

Setting and testing safety equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144

Conditions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144

Setting and testing regulation equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144

Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144

Setting the high-pressure control. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144

Setting the low-pressure control. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144

Practical tips

Notes

134 DKRCC.PF.000.G1.02 / 520H1459 © Danfoss A/S (AC-DSL/MWA), 10 - 2006

Fitters notes Practical Tips - The installation process

Installation process

Planning

Process:

Planning of component location and

tubing layout

Setting up of main components

Piping and component installation

Evacuation

Flushing

Pressure testing

Leak testing

Charging

Setting safety equipment

Testing safety equipment

Setting controls

Testing the complete system and

readjusting controls, etc.

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Installation must be planned so that

Damage to building sections, including

cold room insulation, is minimal.

Components are located functionally

correctly (e.g. adequate air ow to

compressor, condenser, evaporator).

Pipe runs are as short as feasibly possible.

Location of main components

Installation of refrigeration system

Main components (compressor, condenser, evaporator, etc.) must be mounted securely in position, using the accompanying brackets and in accordance with the manufacturer’s instructions.

The compressor must always be secured to a horizontal base. If vibration dampers are supplied, they must also be tted.

Installation must be as rapid as possible so that signicant quantities of moisture, air or other impurities have little chance of collecting in the system.

Compressors and lter driers should therefore be installed last, immediately before evacuating and charging the system.

All openings into the refrigerant system - with absolutely no exception - must be completely sealed against air and water vapour for the duration of any pauses that might occur in installation work.

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Practical tips

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Fitters notes Practical Tips - The installation process

Piping installation

As far as possible, piping must be horizontal or vertical. The exceptions are:

Suction lines, which can be given a slight fall towards the compressor.

Discharge lines, which can have a slight fall away from the compressor.

Pipe xing brackets, clips, etc. must be pitched to suit the pipe diameter and load from components mounted in the lines.

If vibration dampers are tted to the compressor, then suitable vibration eliminators should be tted to suction and discharge piping.

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Oil locks must be mounted in vertical suction lines at a pitch of 1.5 to 5 m depending on running time per cycle. In systems with large load variations it can be necessary to introduce double risers.

Suction lines must also be installed to take account of oil return to the compressor.

In systems with varying loads, the demands are particularly critical at low loads.

Location of other components

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All components should be installed so that they are easily accessible for service and possible repair.

Controls and safety equipment must be located so that testing and adjustment can easily be performed using ordinary tools.

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Fitters notes Practical Tips - The installation process

Compressors in parallel installation

Compressors in parallel must be installed with oil equalization between compressor crankcases, otherwise whichever compressor(s) run most will „steal“ oil from the other compressor(s). Oil equalization can be introduced by installing an equalizing tube between oil sumps. In systems with one equalizing tube, the tube must be installed between compressor oil sumps and must be of such a diameter that both oil and refrigerant vapour are able to ow through it unhindered.

With two equalizing tubes (g. 1)

One tube must be installed between compressor oil sumps, the other between compressor vapour chambers (crankcases). When installing oil equalization in either of the forms described, the compressors must be set up in exactly the same horizontal plane.

Oil level controls (g. 2)

Oil equalization is also possible using oil level regulators. If these are used, the compressors can be installed at dierent levels. However, level controls are much more expensive than equalizing pipes. The following components are necessary with oil level regulation:

Oil separator (1)

Pressure equalizing valve (2)

Oil reservoir (3)

Oil lter (4)

Oil level regulator (5) Remember that each compressor must be

protected with a high-pressure control, e.g. KP7.

Important installation processes

Component storage

The processes that might give rise to contamination of refrigerant systems are:

Component storage

Pipe cutting

Cleaning pipe ends

Soldering

Flare connections

All components must have a temperature not lower than that of their surroundings - before they are opened. This prevents condensation in the components.

For example, components must not be installed immediately after they have been brought from a cold service van into a warm room.

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Practical tips

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Fitters notes Practical Tips - The installation process

Pipe cutting

Pipe cleaning

Tubing must be cut with a pipe cutter or be sawn. Never use any kind of lubricant/coolant.

Remove internal and external burrs with a special deburring tool.

Avoid copper swarf entering the pipe. Use calibration tools to ensure the correct diameter and roundness.

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Blow through the pipe using a blast of dry compressed air or dry nitrogen.

Never use ordinary compressed air; it contains too much moisture. Never blow through piping by mouth.

Piping which has been prepared for later use must be laid ready, with sealed ends, together with the other components.

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Silver soldering (brazing)

Silver solder consists of 30% silver, copper, zinc and tin. The melting range is just over 655°C to about 755°C.

Silver solder will bind only with clean, nonoxidized metal surfaces.

Clean the pipe ends with a special brush and apply ux at once, immediately before soldering.

Silver soldering ux must be suspended in spirit, never water.

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Smear a thin layer of ux around the soldering point after the parts have been joined.

Silver solder can then be used to permanently join dierent materials, e.g. brass/copper and iron/copper.

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Fitters notes Practical Tips - The installation process

Phosphor solder

Use of inert gas when soldering

Phosphor solder consists of 2-15% silver with copper and phosphor. The melting range is about 640°C to 740°C.

Flux must not be used when making phosphor solder connections.

Phosphor solder can only be used to join copper to copper.

At the high temperatures used in soldering, oxidation products (scale) form immediately if the pipe comes into contact with atmospheric air while soldering is taking place.

An inert gas must therefore be blown through the system during soldering. Send a slight ow of dry nitrogen or another kind of inert gas through the tubing.

Do not begin soldering until there is no more air in the component(s) concerned.

Start the operation with a strong ow of inert gas.

Closely observe that no air ow goes into the pipe with inert gas ow.

Reduce the ow to a minimum when soldering is started.

Maintain this slight ow of shielding gas during the whole soldering process.

Soldering must be performed with oxygen and gas, with a slight oxygen decit and a relatively large burner jet.

The solder must not be applied until the melting temperature is reached on the parts being connected.

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Economic soldering

Never use more solder than necessary, otherwise there is a risk of blocking the pipe partially or completely.

Solder quickly so that the oxygen absorption property of the ux is not impaired, i.e. for no longer than about 15 seconds.

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Practical tips

Fitters notes Practical Tips - The installation process

Be careful with the temperature

Flare connections (copper piping)

The temperature must not be higher than necessary.

Therefore draw the ame back slowly when the melting temperature is reached.

External ux residue must be removed by brushing with hot water.

Alloys based on tin or lead are not recommended as solders for refrigerant systems.

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Use only approved refrigeration copper piping. Cut ends at right angles to the piping. Remove all internal and external burrs. Make the are the right size, neither too small nor

too large. Do not compress the are so severely that it

becomes hard. Leave nal tightening up until actual installation.

Evacuation, ushing and charging

Necessary equipment

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Steps to follow:

On completing installation work, the next steps are:

Evacuation and refrigerant charging Leak testing Starting up and adjustment.

Faults, which occur after the system has been started, can necessitate:

Repair of the system.

Vacuum pump Vacuum gauge Charging bottle (or service cylinder

containing refrigerant) (Vacuum pump, vacuum gauge and charging bottle can be obtained assembled as an evacuation and charging board.)

Charging hoses Leak detector

Remove moisture, atmospheric air and inert gas from the system when evacuating.

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Fitters notes Practical Tips - The installation process

Vacuum pump

Vacuum hoses

The vacuum pump should be capable of quickly bringing the system pressure down to about 0.05 mbar.

Pump capacity, e.g. 20 l/minute. Eective evacuation requires large pipe diameters.

Therefore evacuation through “Schraeder” valves is not advisable. Use a “Quick Connector” for compressors with process tube or use the process connectors on the compressor suction and perhaps the discharge stop valve.

The valve spindle must be in its mid position.

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Vacuum hoses and tubes must be as short as possible and the diameter suciently large.

Normally, an ordinary 1/4" charging hose not more than 1 m in length can be used.

Evacuate in two stages with refrigerant ushing between.

The process of evacuation, ushing and charging is described below.

Checking the vacuum pump and hoses

a) Mount the charging hoses between charging board and compressor. Shut o the connections between charging hoses and compressor. b) Start the pump and allow it to suck the pressure down as far as possible. c) Shut o the pump from the rest of the system. d) Stop the pump. e) Read o and register the pressure on the vacuum gauge. The pressure must not be more than 0.05 mbar. f) Check to ensure that the vacuum can be maintained. If not, replace charging hoses and/or leaking valves and/or vacuum oil in the vacuum pump.

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Practical tips

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Fitters notes Practical Tips - The installation process

First evacuation

System vacuum test

Evacuation from suction side of compressor and possibly also the discharge side.

Charging hose(s) mounted between charging board and compressor.

All valves, incl. solenoid valves, open. Automatic regulating valves at maximum

opening. Evacuate system, if possible down to the

pressure previously indicated by the vacuum gauge.

To be performed as described under „Checking the vacuum pump and hoses“. If any leakage is detected:

Approximately localize the leakage by shutting o sections of the system. Retighten are and/or ange connections. Repeat evacuation.

Repeat the test until vacuum is maintained or continue with the next point.

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Flushing and provisional leak testing

Second evacuation

Apply refrigerant pressure to the system (approx. 2 bar overpressure).

Leak-test all connections.

If leakage is detected:

Use a recycling unit and vacuum pump to remove refrigerant from the system.

Repair the leakage. Repeat the process until no system leakage

remains.

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If overpressure remains on the system, use the recycling unit to empty it of refrigerant.

Then evacuate again as described under “First evacuation”.

This will further remove any air and moisture remaining in the refrigerant system.

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Fitters notes Practical Tips - The installation process

Provisional setting of safety equipment

Checking the electrics

Check and set high-pressure control and any

other safety equipment, incl. motor protector

(setting in accordance with scale values).

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Check all wiring.

Test the control system with compressor

motor disconnected.

Check the direction of rotation of the motor.

Swap two phases if necessary.

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Refrigerant charging

After nal evacuation, the system can be charged with refrigerant.

A charging board can be used for the purpose and will, with sucient accuracy, dose the correct quantity of refrigerant for the system. High accuracy is needed in systems without receiver.

If the system has a charging valve, refrigerant can be supplied in the form of liquid to the liquid line. Otherwise the refrigerant can be supplied as vapour to the compressor suction stop valve with the compressor running.

Caution:

Too little superheating during the charging process can cause liquid hammer in the compressor.

Charging must be continued until no vapour formation appears in the sight glass - unless vapour formation is due to other faults, see the section “Trouble shooting - Fault location”. If the necessary quantity of refrigerant is not known, use the method last described.

Here however, it is necessary the whole time to check that the condensing pressure and suction pressure remain normal and that the Thermostatic expansion valve superheat is not too low.

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Practical tips

Fitters notes Practical Tips - The installation process

Condensing pressure too high

Setting and testing safety equipment

Conditions

Too high a condensing pressure during the charging process can mean that the system has been overcharged with refrigerant and must be partly drained.

Always use the recycling unit if it becomes necessary to drain o refrigerant.

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Final setting and testing of safety equipment must be performed with all mechanical and electrical equipment installed and the system running.

The functions must be checked with accurate instruments. See also the chapter “Trouble Shooting” , section “Measuring Instruments“ with reference to the instructions for the equipment concerned.

Setting and testing regulation equipment

Procedure

Setting the high-pressure control

Setting the low-pressure control

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If a constant-pressure valve is installed, make a coarse setting.

Set the expansion valve superheat. Using a pressure gauge, set the constant

pressure valve. Set the capacity regulator, if installed. Set the thermostats (using a thermometer).

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Increase the condensing pressure to permissible maximum and use a pressure gauge to set the high-pressure control.

Reduce the suction pressure to the permissible minimum and use a pressure gauge to set the low-pressure control.

Attention: When making the above settings, constantly check whether the system

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is operating normally (pressure, etc.). Finally - ensure that correct refrigerant identi-

cation labels are axed to the system in order that correct future servicing is ensured.

Danfoss Praktiske tips Service guide

Specifications and Main Features

Frequently Asked Questions

User Manual