Carrier 30XW Installation, Operation And Maintenance Instructions

Also see for 30XW: Operation instructions User guide Installation, operation and maintenance instructions

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Carrier 30XW Installation, Operation And Maintenance Instructions Manual pdf 28 page image

28impurities maybe the cause of the wear or corrosionby puncture.• Filter the heat exchange fluid check and carry outinternal inspections as described in EN 378.• In case of re-testing please refer to the maximumoperating pressure given on the unit nameplate.• The reports of periodical checks by the user or operatormust be included in the supervision and maintenance file.RepairAny repair or modification, including the replacement ofmoving parts:• must follow local regulations and be made by qualifiedoperators and in accordance with qualified procedures,including changing the heat exchanger tubes.• must be made in accordance with the instructions of theoriginal manufacturer. Repair and modification thatnecessitate permanent assembly (soldering, welding,expanding etc.) must be made using the correctprocedures and by qualified operators.• An indication of any modification or repair must beshown in the monitoring and maintenance file.RecyclingThe unit is wholly or partly recyclable. After use it containsrefrigerant vapours and oil residue. It is coated by paint.Operating lifeThe evaporator and oil separator are designed for:• prolonged storage of 15 years under nitrogen chargewith a temperature difference of 20 K per day.• 452000 cycles (start-ups) with a maximum differenceof 6 K between two neighbouring points in the vessel,based on 6 start-ups per hour over 15 years at a usagerate of 57%.Corrosion allowances:Gas side: 0 mmHeat exchange fluid side: 1 mm for tubular plates in lightlyalloyed steels, 0 mm for stainless steel plates or plates withcopper-nickel or stainless steel protection.11.2.1 - Evaporator30XW chillers use a flooded multi-tube evaporator. Thewater circulates in the tubes and the refrigerant is on theoutside in the shell. One vessel is used to serve bothrefrigerant circuits. There is a centre tube sheet whichseparates the two refrigerant circuits. The tubes are 3/4”diameter copper with an enhanced surface inside and out.There is just one water circuit with two water passes (onepass with option 100C, please refer to chapter 6.5).The evaporator shell has a polyurethane foam thermalinsulation and a water drain and purge.It has been tested and stamped in accordance with theapplicable pressure codes. The maximum standard relativeoperating pressure is 2100 kPa for the refrigerant-side and1000 kPa for the water-side. These pressures can be differentdepending on the code applied. The water connection ofthe heat exchanger is a Victaulic connection.The products that may be added for thermal insulation ofthe containers during the water piping connection proceduremust be chemically neutral in relation to the materials andcoatings to which they are applied. This is also the case forthe products originally supplied by Carrier.11 - MAJOR SYSTEM COMPONENTS AND OPERATIONDATA11.1 - Direct-drive twin-screw compressor withvariable capacity slide valve• 30XW units use 06T geared twin-screw compressorsequipped with a variable capacity slide valve forcontrol between 35% and 100% of full load. Forcompressor that are able to monitor down to 15%, thestages between 15% and 30% may be continuous ordiscontinuous.• The 06T compressor models used are:06TT-266, 06TT-301, 06TT-356, 06TU-483, 06TU-554,06TV-680, 06TV-753, 06TV-81911.1.1 - Oil filterThe 06T screw compressor has an independent oil filter.11.1.2 - RefrigerantThe 30XW is a liquid chiller operating only with refrigerantR-134a.11.1.3 - LubricantThe 06T screw compressor is approved for use with thefollowing lubricant: CARRIER MATERIAL SPEC PP47-32.11.1.4 - Oil supply solenoid valveAn oil supply solenoid valve is installed on the oil returnline as standard to isolate the compressor from oil flowwhen the compressor is not operating. The oil solenoidvalve is field replaceable.11.1.5 - Capacity control systemThe 06T screw compressor has an unloading system that isstandard on all compressors. This unloading system consistsof slide valve that permits changing the length of the screwused for the refrigerant compression. This valve is controlledby the action of a piston controlled by two solenoid valveson the oil return line.11.1.6 - Suction valve (option 92)An isolating valve can be added to ease maintenane oncompressor. This valve can be moved only withoutpressure differential upstream and downstream of thisvalve.11.2 - Pressure vesselsGeneralMonitoring during operation, re-qualification, re-testingand re-testing dispensation:• Follow the regulations on monitoring pressurisedequipment.• It is normally required that the user or operator setsup and maintains a monitoring and maintenance file.• If no regulations exist or to complement regulations,follow the control programmes of EN 378.• If they exist follow local professional recommendations.• Regularly inspect the condition of the coating (paint)to detect blistering resulting from corrosion. To do this,check a non-insulated section of the container or therust formation at the insulation joints.• Regularly check for possible presence of impurities(e.g. silica grains) in the heat exchange fluids. These