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The main material in Aermec heat exchangers is aluminium.

Aluminum is a very reactive metal, which is easily oxidized on its surface. As 

long as this hard layer of aluminum oxide remains intact, the aluminum at 

the base will remain resistant to corrosion (unlike other materials, such as 

steel, where the oxide layer peels off the surface and flakes off, allowing the 

constant attack of the underlying metal).

However, aggressive environments can damage the oxide layer, which may 

not regenerate as quickly as necessary to provide the product with sufficient 

protection.

These harsh environments are typified by very high or very low pH levels.

Normally, aluminum’s protective oxide layer is generally stable in the pH 

range of 4.5 to 8.5; the lack of exposure to excessively acidic or basic pH 

conditions is not in itself sufficient to exclude the need for appropriate pro

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tective treatments on the batteries.

The presence of salt (associated with marine environments) as well as the 

presence of other aggressive substances can in fact induce widespread or 

localized galvanic corrosion (pitting or anthill corrosion).

 OTHER RISK FACTORS FOR CORROSION

The principal cause of corrosion is elevated humidity and/or temperatures 

in the presence of contaminant gases. These conditions alone, or in combi

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nation, accelerate the natural corrosion process in metals.

 Humidity

Moisture in air can be considered the lifeblood of galvanic corrosion. A gal

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vanic  corrosion  cell  requires  an  electrolyte  or  current  carrying  media,  to 

reach a dynamic state. The electrolyte can be water or any water-soluble 

substance with good conducting properties. Moisture in the air is one such 

electrolyte. Humid air contaminated with corrosive gasses further accelera

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tes the corrosion rate as the air’s current carrying otential increases.

 Temperature

Chemical reactions generally depend on the temperature, for reactions that 

involve corrosion of aluminum by an increase in temperature, faster reac

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tion frequencies usually arise.

 Corrosive gases

Not  all  gases  cause  corrosion.  Specifically,  we  are  concerned  with  three 

types of gases:

— 

Acidic gases, such as hydrogen sulfide, sulfur oxides, chlorides, hydrogen 

fluoride (HF) and nitrogen oxides;

— 

Caustic gases, such as ammonia;

— 

Oxidizing gases, such as ozone

 

Of the gases that can cause corrosion, the acidic gases are typically the 

most harmful.

FLOW OF ELECTRONS

FLOW OF IONS (+)

FLOW OF IONS (-)

ELECTROLYTE

ANODE

AND-

CATHODE

Keeping the surfaces of the microchannel coils clean is essential to ensure 

the correct operation of the unit and to avoid punctures on the coil with the 

consequent loss of refrigerant gas which would lead to the replacement of 

the coil itself.

WARNING Damage to the coil due to neglect or lack of or poor clea

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ning is not covered by the warranty.

Dirt, grease, oil, and other foreign material must be removed periodically from 

the surface of the battery according to the following recommendations.

Required elements:

— 

Personal protective equipment

— 

Hot water

— 

High-pressure washing

Procedure:

Use a high-pressure washer with a large cast and enough force to remove all 

foreign material, proceed with care to avoid damage and possible wear of the 

louvers.

Lastly, also rinse the carpentry and the fans thoroughly to be sure that all im

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purities have been removed.

 

 Aermec  assume no liability for the completeness of the information con

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tained in this document.  

 BASIC PRINCIPLES ON MICROCHANNEL COIL CORROSION 

 CLEANING MICRO-CHANNEL COIL

Summary of Contents for NRV 0550

Page 1: ...EN Technical Manual TRANSLATION FROM ORIGINAL 5523421_02 22 02 OUTDOOR CHILLER MICROCHANNEL COILS EASY AND QUICK TO INSTALL COMPACT MODULE RELIABILITY AND MODULARITY NRV 0550...

Page 2: ......

Page 3: ...ce and in depth engineering research and it is manufactured using top quality materials and cutting edge technologies In addition the CE mark guarantees that our appliances fully comply with the requi...

Page 4: ...15 BASIC PRINCIPLES ON MICROCHANNEL COIL CORROSION 16 CLEANING MICRO CHANNEL COIL 16 OPERATING RANGE 17 PERFORMANCE SPECIFICATIONS 18 GENERAL SPECIFICATIONS 18 ELECTRICAL DATA 19 DIMENSIONS AND WEIGHT...

Page 5: ...e ci dessus est conforme aux normes d harmonisation relatives de l Union Der Gegenstand der genannten Erkl rung entspricht den diesbez glichen harmonisierten Normen der europ ischen Gemeinschaft El o...

Page 6: ...200 L WSH 1202 WSH 1402 WSH 1602 WSH 1802 WSH 2002 WSH 2202 WSH 2502 WSH 2802 NRG 0802 L NRG 0804 L Bevilacqua VR Commercial Director Luigi Zucchi This declaration of conformity has been released und...

Page 7: ...low heat load conditions EXTENDED OPERATING RANGE This range can work at full load with outdoor temperature up to 50 C This occurs in the high efficiency versions and also for example in versions wit...

Page 8: ...t recovery Without heat recovery D With desuperheater 11 Version A High efficiency E Silenced high efficiency 12 Coils Aluminium micro channel O Painted aluminium microchannel R Copper Copper S Copper...

Page 9: ...refrigerant gas to the evaporator recovery and the coil Liquid indicator It is used to verify that the expansion system is powered correctly and the presence of humidity in the cooling circuit STANDA...

Page 10: ...e always a prompt diagnosis of the unit operation Creation of operation time periods required for efficient programming A self adaptive logic is used to defrost This logic allows you to adjust the num...

Page 11: ...c circuit system side System side heat exchanger plate heat exchanger Heat exchanger electric resistance Water filter Flow Switch Differential pressure switch Safety valve Manual air vent valve Automa...

Page 12: ...12 PRINCIPLE FUNCTIONING DIAGRAMS NRV0550 with mechanical thermostatic valve Schema frigorifero NYB Evaporator Condenser Condenser Evaporator...

Page 13: ...high pressure switch finned heat exchanger scroll compressor drier filter insulated pipe regulation line Pressure connection high pressure side temperature probe high pressure transducer low pressure...

Page 14: ...fold KREC Accessory kit to remote the electric power supply input to the back RIF Power factor correction Connected in parallel to the motor allowing about 10 reduction of input current COMPATIBILITY...

Page 15: ...te corrosion Within the manufacturing plants corrosive gas may result from the proces sing of chemicals or by the typical industrial processes used in manufactu ring Potential sources of risk to be co...

Page 16: ...oisture in the air is one such electrolyte Humid air contaminated with corrosive gasses further accelera tes the corrosion rate as the air s current carrying otential increases Temperature Chemical re...

Page 17: ...mend you first contact our technical sales service Note If the unit is installed in particularly windy areas you must provide a windbreak to prevent unit malfunctions It should be installed if wind sp...

Page 18: ...at exchanger Type plates Number no 1 Resistance no W Connections with Grooved Joints Diameter A in out 6 E in out 6 Desuperheater Heat Exchanger Type plates Number no 1 Resistance no W Connection type...

Page 19: ...GHTS Size Notes ver 0550 Electrical data Standard unit Height A mm 2480 E mm 2480 Width A mm 2200 E mm 2200 Length A mm 1190 E mm 1190 Vacuum weight A kg 1105 E kg 1105 Size Notes ver 0550 Electrical...

Page 20: ...24 61 48 38 80 63 51 0550E TA d b 10 25 35 46 10 25 35 46 10 25 35 46 10 25 35 46 TW out 4 7 10 15 Glycol 10 0 00 0 00 0 00 Pc 118 5 104 0 93 1 84 7 131 6 115 5 103 5 93 5 144 0 126 3 113 5 165 6 145...

Page 21: ...nsitive to the phenomenon of extra oxygenation of the water an event that can be encouraged by the incorrect positioning of some components This phenomenon can trigger corrosion processes and subseque...

Page 22: ...0 955 0 947 0 939 0 932 0 924 Pe 1 0 996 0 994 0 992 0 99 0 988 0 986 0 984 0 982 0 98 Dp 1 1 082 1 102 1 143 1 201 1 271 1 351 1 435 1 52 1 602 CORRECTIVE FACTORS GLYCOL Qwc Water flow rate correctiv...

Page 23: ...e at the moment of installation 1200 Xg Yg 1 3 2 4 Top View WEIGHT WITHOUT PACKING Module 1 Model Version Module kit Weight kg Barycentre mm Distribution of weights on the supports NRV 0550 00 no Hydr...

Page 24: ...C S p A Via Roma 996 37040 Bevilacqua VR Italia Tel 39 0442 633111 Fax 39 0442 93577 marketing aermec com www aermec com Aermec reserves the right to make all modification deemed necessary for improvi...

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