SUPPLEMENT TO OPERATION MANUAL Modular Air Handling Units CAIRplus ECOTWINcool

Transcription

1 SUPPLEMENT TO OPERATION MANUAL Modular Air Handling Units CAIRplus ECOTWINcool

2 Table of Contents Overview of units and packaged content... 3 Adiabatic cooling... 3 Design features... 4 Fan arrangement... 4 Hood (protective hood of the air humidifier assembly)... 5 Various hood sizes... 5 Nozzle employed... 6 Solenoid valve employed... 7 Controls... 7 Maintenance... 7 Copyright note Disclosing, copying, distributing or taking any action in reliance on the contents of this document is strictly prohibited without express prior consent. Violations entail liability for any damages or other liability arising. All rights in relation to patents, utility patents or design patents are reserved. 2 PR GB Subject to modifications R1-05/2016

3 Overview of units and packaged content Return air Exhaust air Supply air Outside air Fig. 1: Indirect adiabatic cooling with double-plate heat exchanger Adiabatic Cooling The air handling units CAIRplus for an air flow rate of 3,000 to 23,000 m³/h can be delivered ex factory with adiabatic cooling. Return air is humidified up to saturation. The coolness resulting from evaporation is then transferred to the supply air via an energy recovery system. Then the cooled supply air can be cooled down further to the desired temperature or dehumidified in the downstream cooler battery. The ECOTWINcool double-plate heat exchanger allows energy-saving adiabatic cooling with directly sprayed heat exchanger plates. The heat exchanger surfaces of the energy recovery system are also used as evaporation surface. Completely separate intake and return air flows are a prerequisite for this process. Epoxide-coated and additionally sealed heat exchangers are therefore used. In the interior, special fine atomizer nozzles humidify the return air at a pressure of 4-6 bar, so that the surfaces of the double-plate heat exchanger are uniformly wetted and operation without a booster pump is possible. Since no circulation water is used, the operation is properly hygienic. With efficiencies of up to 75 percent, very high cooling capacities are achieved based on the saturation temperature. PR GB Subject to modifications R1-05/2016 3

4 Design features Plate-type heat exchanger Epoxy resin coating Additionally sealed foldings Tested for leaks Condensate tray for model "V" Permeate from reverse osmosis unit is corrosive The tray is therefore made of Humidifier segment The duct bend engages in the plate-type heat exchanger so that no water precipitates on the units walls Material Chamber models The humidified air does not come into contact with the ECOTWIN-V humidification chamber's internal skin Internal skin made of Aluzink or RAL9002 is sufficient the chamber must not be especially sealed. Trap A trap must be provided on site Especially for a suction return fan, a ball trap should be provided Water quality Feed water from the tap contains lime and salts which can lead to depositions. Water treatment is therefore necessary Up to a conductivity of 500µS/cm, softening is usually sufficient For higher conductivities, a reverse-osmosis unit is required Water pressure The adiabatic cooling works for water pressures of 4-6 bar, whereby a pressure of 5 to 6 bar should be aspired Fan arrangement Return fan intake Supply fan intake the ideal arrangement for plants where high leak tightness is required the ideal arrangement for plants where high pressure differentials prevail Return fan - pressure Supply fan - suction intake there is the danger of backflows, where water gets into the fan chamber. Plan sufficient clearance for plug fans. possibly employ both fans for intake Return fan intake supply fan exhausting occasionally used in plants with inferior exhaust air quality, such as kitchens this design is only practicable, however, if the system pressures are not very high the danger of leakage is not as great because of prevailing negative pressure in the damp area. be sure to pay special attention to the large differential pressure in the heat exchanger area. 4 PR GB Subject to modifications R1-05/2016

5 Hood (protective hood of the air humidifier assembly) Hood Nozzle fitting Fig. 2: Hood The hood ensures that the humidified air or the osmosis water only remains in the heat exchanger and does not get into the rest of the air conditioning unit. Various hood sizes CAIR type Number of nozzles Nozzle pitch NW [each] Height NH [each] NH: Number of nozzles in height NW: Number of nozzles in width TH: Nozzle distribution in height TB: Nozzle distribution in width TWM:Middle nozzle distribution for two hoods Total TW [mm] TWM [mm] Height TH [mm] Interior height [mm] Interior width [mm] Number of hoods next to each other PR GB Subject to modifications R1-05/2016 5

6 Height Front view of the hood Fig. 3: Front view of a hood Height Fig. 4: Front view of two hoods Nozzle employed This is a nozzle with a ¼ inch screw thread is employed as material Nozzle wrench width 12 6 PR GB Subject to modifications R1-05/2016

7 Solenoid valve employed Suited for use in partly aggressive liquid media Material: stainless steel The solenoid valve is mounted by the manufacturer Connected currentless Connection ½ inch Voltage 230V IP 65 class Ambient temperature -10 to 50 C Operating pressure max. 10 bar Power 20VA Fig. 5: Solenoid valve/symbol Controls The activation of adiabatic cooling is done by opening of a solenoid valve. Requirements for activation are: Cooling demand is present The saturation temperature of the return air must lie at least 4 C below the outside temperature Partial-load operation is executed by cycling the solenoid valve. ON [sec] OFF [sec] Tab. 1: Overview of nozzle cycling Nozzle cycle Power [%] Consumption [%] Maintenance Maintenance intervals Inspection before/after cooling season Cleaning The maintenance intervals depend on the quality of the water used. For permeate from reverse-osmosis units, the maintenance intervals can be longer than when using softened water. Generally, the units should undergo inspection before and after every cooling season. Especially check for any deposits on the plate heat exchanger as well as on the nozzle. If deposits have formed on the plate exchanger, then the function of the water treatment should be examined. Deposits on the nozzles can almost always be eliminated in an ultrasonic bath. The 3-part nozzle is previously taken apart. PR GB Subject to modifications R1-05/2016 7

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