"A" Ductable Liquid Chillers with Integrated Hydronic Module

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9 - WATER CONNECTIONSFor size and position of the unit water inlet and outlet connectionsrefer to the certified dimensional drawings supplied withthe unit. The water pipes must not transmit any radial or axialforce to the heat exchangers nor any vibration.The water supply must be analysed and appropriate filtering,treatment, control devices, shutoff and bleed valves and circuitsbuilt in, to prevent corrosion (example: damage to the protectionof the tube surface if the fluid is polluted), fouling and deteriorationof the pump fittings.Before any start-up verify that the heat exchange fluid iscompatible with the materials and the water circuit coating.In case additives or other fluids than those recommended byCarrier s.a are used, ensure that the fluids are not considered asa gas, and that they belong to class 2, as defined in directive97/23/EC.Carrier s.a. recommendations on heat exchange fluids:1. No NH 4+ ammonium ions in the water, they are verydetrimental for copper. This is one of the most importantfactors for the operating life of copper piping. A contentof several tenths of mg/l will badly corrode the copperover time.2. Cl - Chloride ions are detrimental for copper with a risk ofperforations by corrosion by puncture. If possible keepbelow 10 mg/l.3. SO 42-sulphate ions can cause perforating corrosion, iftheir content is above 30 mg/l.4. No fluoride ions (2.8 K. Values between 10 and 25can be recommended. This will facilitate scale deposit thatcan limit corrosion of copper. TH values that are too highcan cause piping blockage over time. A total alkalimetrictitre (TAC) below 100 is desirable.8. Dissolved oxygen: Any sudden change in water oxygenationconditions must be avoided. It is as detrimental todeoxygenate the water by mixing it with inert gas as it isto over-oxygenate it by mixing it with pure oxygen. Thedisturbance of the oxygenation conditions encouragesdestabilisation of copper hydroxides and enlargement ofparticles.9. Specific resistance – electric conductivity: the higher thespecific resistance, the slower the corrosion tendency.Values above 3000 Ohm/cm are desirable. A neutralenvironment favours maximum specific resistance values.For electric conductivity values in the order of 200-6000S/cm can be recommended.10. pH: Ideal case pH neutral at 20-25°C (7 < pH < 8).ATTENTION: Charging, adding or draining fluid from thewater circuit must be done by qualified personnel, using airvents and materials suitable for the products. The watercircuit charging devices are field-supplied.Charging and removing heat exchange fluids should be donewith devices that must be included on the water circuit by theinstaller. Never use the unit heat exchangers to add heatexchange fluid.9.1 - Operating precautions and recommendationsThe water circuit should be designed to have the least numberof elbows and horizontal pipe runs at different levels. Belowthe main points to be checked for the connection:• Comply with the water inlet and outlet connections shownon the unit.• Install manual or automatic air purge valves at all highpoints in the circuit.• Use an expansion device to maintain pressure in thesystem and install a safety valve as well as an expansiontank.Units with a hydronic module include the safety valve andthe expansion tank.• Install thermometers in both the entering and leavingwater connections.• Install drain connections at all low points to allow thewhole circuit to be drained.• Install stop valves, close to the entering and leaving waterconnections.• Use flexible connections to reduce the transmission ofvibrations.• Insulate all pipework, after testing for leaks, both toreduce thermal leaks and to prevent condensation.• If the external unit water pipes are in an area, where theambient temperature is likely to fall below 0°C, insulate thepiping and add an electric heater. The internal unit pipingis protected down to -20°C.NOTE: For units not equipped with a hydronic module ascreen filter must be installed as close to the heat exchangeras possible, in a position that is easily accessible for removaland cleaning. Units with hydronic module are equipped withthis type of filter.The mesh size of the filter must be 1.2 mm.The plate heat exchanger can foul up quickly at the initialunit start-up, as it complements the filter function, and theunit operation will be impaired (reduced water flow rate dueto increased pressure drop).Before the system start-up verify that the water circuits areconnected to the appropriate heat exchangers (e.g. noreversal between evaporator and condenser).Do not introduce any significant static or dynamic pressureinto the heat exchange circuit (with regard to the designoperating pressures).The products that may be added for thermal insulation of thecontainers 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 s.a.16
9.2 - Hydronic connectionsThe diagram on the next page shows a typical hydronicinstallation.When charging the water circuit use air vents to evacuate anyresidual air pockets.9.3 - Frost protectionThe plate heat exchangers, the piping and the hydronic modulepump can be damaged by frost, despite the built-in anti-freezeprotection of these units.The frost protection of plate heat exchanger and all hydronicmodule components is guaranteed down to -20°C (sizes 040-080 only) by automatically energized heaters and pump cycling.- To prevent corrosion by differential aeration, the completedrained heat transfer circuit must be charged withnitrogen for a period of one month. If the heat transferfluid does not comply with the Carrier S.A. regulations,the nitrogen charge must be added immediately.9.4 - Installation of the accessory condensaterecovery panRef. No.: 30RY 900 022 EE -- 30RY 017-03330RY 900 032 EE -- 30RY 040-080In heat pump mode it may be necessary to remove the water.Carrier can supply an accessory condensate recovery pan to bepositioned under the unit. This pan is connected to the condensaterecovery systems via a threaded 1" diameter gas pipe.Never switch off the evaporator and hydronic circuit heaters orthe pump, otherwise frost protection cannot be guaranteed.For this reason the main unit disconnect switch (QS101) aswell as the auxiliary protection switch (QF101) for the heatersmust always be left closed (for location of QS and QF 101 seewiring diagram).To ensure frost protection down to -20°C, water circulation inthe water circuit must be maintained by periodically switchingon the pump. If a shut-off valve is installed, a bypass must beincluded as shown below.Winter positionF1AOFBLegendA UnitB Water networkC ClosedO Open2IMPORTANT:Depending on the atmospheric conditions in your area youmust do the following when switching the unit off in winter:- Add ethylene glycol with an adequate concentration toprotect the installation up to a temperature of 10 K belowthe lowest temperature likely to occur at the installationsite.- If the unit is not used for an extended period, it isrecommended to drain it, and as a safety precautionintroduce ethylene glycol in the heat exchanger, usingthe water entering purge valve connection.At the start of the next season, refill the unit with waterand add an inhibitor.- For the installation of auxiliary equipment, the installermust comply with basic regulations, especially forminimum and maximum flow rates, which must bebetween the values listed in the operating limit table(application data).Legend1 Condensate recovery pan2 Connection17
Page 1: 30RY 017-080 "A"Ductable Liquid Chi
Page 4 and 5: 1 - INTRODUCTIONPrior to the initia
Page 6 and 7: During refrigerant removal and stor
Page 8 and 9: Checks before system start-upBefore
Page 10 and 11: 4 - PHYSICAL DATA30RY 017 021 026 0
Page 12 and 13: 6 - APPLICATION DATA6.1 - Unit oper
Page 14 and 15: 7 - ELECTRICAL CONNECTION30RY 017-0
Page 18 and 19: Typical hydronic circuit diagram (3
Page 20 and 21: When the circuit is cleaned, read t
Page 22 and 23: Accessory reference number:30RY-017
Page 24 and 25: Pressure12 - MAINTENANCEAny technic
Page 26 and 27: Bar Saturated bubble Saturated dew
Page 28 and 29: Service CCarry out the operations l
Page 30 and 31: Unit start-upChilled water pump sta
Page 32: Order No.: 13427-76, 04.2002 - Supe

"A" Ductable Liquid Chillers with Integrated Hydronic Module

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