Robur AD, AD14, AD20 Design Manual

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Design manual
AD evaporative coolers
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Revision: A Code: D-MNL053EN
This Design manual has been drawn up and printed by Robur S.p.A.; whole or partial reproduction of this Design manual is prohibited. The original is led at Robur S.p.A. Any use of this Design manual other than for personal consultation must be previously authorised by Robur S.p.A. The rights of those who have legitimately led the registered trademarks contained within this publication are not aected. With the aim of continuously improving the quality of its products, Robur S.p.A. reserves the right to modify the data and contents of this Design manual without prior notice.
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Design manual AD evaporative coolers
INDEX OF CONTENTS
1 Premise .........................................................................................
2 Cooling and ventilation .................................................
2.1 Microclimate within the room ....................................
2.2 Safety, health and productivity ..................................
3 The technical solution .....................................................
3.1 The result and the advantages ...................................
3.2 System operation ............................................................
3.3 Performances of the system ........................................
4 Air psychrometric chart .................................................
5 The evaporative cooler ..................................................
5.1 Evaporative cooler operation .....................................
5.2 Description of the automatic cleaning system
...............................................................................................
5.3 Routine maintenance ....................................................
6 Design of a cooling and ventilation system
..............................................................................................................
6.1 Outdoor summer design conditions .......................
6.2 Air diusers installation height in the building
...............................................................................................
6.3 Number of air renewals required depending on
the type of activity in the building .........................
6.4 Exhaust air evacuation ................................................
p.4 p.4
p.4 p.4
p.4 p.5
p.5 p.5
p.6 p.8
p.8
p.8 p.9
p.9 p.9
p.9
p.10 p.10
7 Choice of models and number of coolers
to be installed .......................................................................
7.1 Available range ..............................................................
7.2 Sizing examples .............................................................
7.3 Evaporative cooler installation .................................
8 Electrical and water supply network ...............
8.1 Water supply network .................................................
8.2 Electrical supply network ...........................................
9 Evaluation of the eective eciency of
the coolers................................................................................
9.1 Water consumption is synonymous with
eciency ..........................................................................
9.2 Evaporative packs crossing speed ..........................
10 Control and regulation solutions .......................
10.1 ECO basic remote control ..........................................
10.2 EVO advanced remote control .................................
10.3 Centralized control .......................................................
11 Diusion plenums ............................................................
11.1 Dimensions .....................................................................
12 Technical data and dimensions ............................
12.1 Technical characteristics .............................................
12.2 Dimensions .....................................................................
12.3 Installation examples ...................................................
p.10 p.10
p.10 p.10
p.11 p.11
p.12
p.12
p.12 p.12
p.13 p.13
p.13 p.14
p.16 p.16
p.17 p.17
p.17 p.18
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97%
X
Y
700%
X
1 PREMISE
The purpose of this Design manual is to provide a rst set of in­formation on the operation, design and characteristics of cool­ing systems with evaporative coolers Robur AD. Robur also provides a spreadsheet for a preliminary design of
cooling systems with Robur AD units. The Robur technical service is always at your disposal for any fur­ther technical information on the application and use of these appliances.
2 COOLING AND VENTILATION
The evaporative cooling system is the most modern technology for cooling and ventilation of large rooms:
▶
production and crafts premises
▶
commercial premises and warehouses
▶
sports premises in general This system allows you to equip even large rooms with summer ventilation and cooling system to improve the comfort of peo­ple, increase their well-being and productivity, without com­mitting large capital for plant expenses, without incurring high operating costs for energy consumption, without producing en­vironmental impact and without the risk of power blackouts for over-demand.
2.1 MICROCLIMATE WITHIN THE ROOM
Inside a large room, such as an industrial building, a microcli­mate is established during the hot seasons that is dicult for the people who work there to endure. The heat input of process plants, electrical power plants and building structures which, when hit by the sun, transmit a high level of thermal energy to the internal air, often cause an unbear­able thermal condition in the environment.
Table2.1 NASA Report CR-1205-1
Ambient temperature 23 °C 26 °C 29 °C 32 °C 35 °C 37 °C 40 °C
Loss in productivity 3% 8% 18% 29% 45% 62% 79% Loss in accuracy - 5% 40% 300% 700% - -
Furthermore, during the night, when the room is closed, the heat stagnates inside the room, creating already in the morning conditions of poor comfort. In addition to all this, there is usually a lack of proper air renewal necessary for the disposal of exhaust air, sometimes harmful to the health of workers.
2.2 SAFETY, HEALTH AND PRODUCTIVITY
The conditions of discomfort caused by high temperatures with­in an industrial environment cause operators to experience the so-called "heat stress", which begins to be eective above 27 °C causing:
▶
Lowering of morale, delays and absenteeism
▶
reduced attention to safety, increase in the percentage of injuries
▶
potential health issues
▶
reduced productivity, reduced production quality Research has shown that this working condition adversely af­fects productivity and production quality, as shown for example by a NASA report:
Figure2.1 NASA Report CR-1205-1
100%
80%
60%
40%
20%
0%
X = internal temperature Y = productivity Z = loss of accuracy
NASA Report CR-1205-1 shows for example that when temper­atures inside the building rise over 29 °C, productivity drops by
92%
82%
71%
55%
38%
21%
23°C 26°C 29°C 32°C 35°C 37°C 40°C
700%
500%
Z
300%
100%
18% and quality decreases by 40% due to increase in working errors.
0%
0%
23°C 26°C 29°C 32°C 35°C
3 THE TECHNICAL SOLUTION
To improve the summer microclimate inside a large room and reach an adequate level of well-being, the environment must be ventilated with cooled air and many new air renewals must be granted to neutralize all heat supply. The continuous renewal of the ambient air prevents the accu­mulation of heat inside the building and prevents the excessive increase of the internal temperature. The air renewal also allows to improve the level of environmental
hygiene, to dispose of any smells or hazardous gases and to im­prove productivity and safety of people. A ventilation and cooling system with AD units consists of evap­orative coolers that cool the air with a natural principle and not through a refrigeration cycle. The evaporative cooler is an appliance that cools the air by re­ducing the sensible heat contained in it. The reduction of the sensible heat is due to the evaporation
5%
300%
40%
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process of the water that comes into contact with the treated air: the air taken from the outside passes through cellulose panels of particular structure wet with water, gives up part of its heat during the process of evaporation of the water and lowers its temperature. A fan, incorporated in the cooler, provides for the supply of the cooled air into the room.
The operating principle is very simple: if the system expels all the introduced air, the system produces maximum eciency, grants all the planned air renewals and cools the environment under the design conditions. It is also possible to have a slightly lower extract air ow than the supplied one (but not less than 80%), which allows the room to be kept slightly overpressurised compared to the outside, pre­venting the outside hot air from re-entering the room through
3.1 THE RESULT AND THE ADVANTAGES
The absence of refrigerating units reduces by 70% the system cost and by 80% the electrical energy consumption, which is reduced to that necessary for the fan operation, signicantly re­duces the size of the systems and simplies installation, opera­tion and maintenance. In general, the advantages that can be obtained with this solu­tion are:
▶
treatment of large volumes of air to achieve many hourly air renewals
▶
air cooling
▶
possibility of ventilation only in the less hot seasons
▶
possibility of partial or dierentiated management for dier-
the natural openings. The ideal condition is to place the air diusers away from the openings (windows, doors, etc.) and distribute them evenly in­side the room. By opening a window away from the diusers, the air passes through the room cooling it before being extracted. By calculating the correct dimensions of the evacuation open­ings the maximum eciency of the system is reached. The sys­tem must be able to extract the large volume of air supplied so as not to reduce the eectiveness of the system. If the available openings are not sucient, it is necessary to add forced air extraction systems (extraction towers). Failure to comply with these conditions precludes the planned air renewal, reduces the cooling eect and increases the relative humidity inside the room.
ent areas of the room
▶
low cooling system costs, low running costs, low mainte­nance costs
▶
no use of environmentally harmful refrigerant gases (such as CFC/HFC and greenhouse gases)
▶
improvement of hygiene in the room
▶
increase of the productivity, quality and safety of internal sta
3.3 PERFORMANCES OF THE SYSTEM
The evaporative cooling system exploits the air adiabatic satura­tion process: the unsaturated humid air is saturated by bringing it into very close contact with water, so that heat exchanges take place only between air and water without other exchanges with the outside. All the heat that the water receives from the air serves to evap-
3.2 SYSTEM OPERATION
orate part of it, so the enthalpy of the residual water remains unchanged as well as its temperature. It follows that even the enthalpy of air does not change.
3.2.1 Ventilation and cleaning of the room
The evaporative cooling system is a system that works dynami­cally and works on the basis of a natural principle: it introduces large quantities of cooled external air into the room and extracts the exhausted hot air through doors, windows and other evacu­ation openings that are left open.
The air temperature is therefore reduced, up to the maximum temperature of the water, while its humidity increases. Since the enthalpy of the air is the sum of elements as a function of temperature (sensible heat) and of an element as a function of humidity (latent heat), if its temperature decreases and the hu­midity increases, it means that the sensible heat has decreased and the latent heat has increased (unchanged enthalpy). Of
Figure3.1 Air ow in the room
course, the system increases its air cooling capacity as the rela­tive humidity of the outdoor air decreases: the drier the outside air is, the higher its possibility of saturation, the higher the re­duction of the sensible heat contained in it, therefore the greater the decrease of the obtainable air temperature. The cooling capacity of the air is also due to the technical char­acteristics of the exchange device (the evaporator) or to its satu­ration eciency: in fact, the longer the time and surface contact between air and water, the more the water evaporates and the air temperature (sensible heat) decreases. The AD evaporative cooler is equipped with a high saturation eciency evaporating unit which produces a good level of cool­ing even at relative air humidity values of around 70%. The temperature of the air supplied to the room is a function of the dierent conditions of the outside air, according to Table
3.1
p.5
.
Table3.1 Temperature of the air supplied to the room
External temper-
ature
25 °C 13,7 15,4 17,0 18,6 20,0 21,3 22,6 30 °C 17,0 19,1 21,0 22,8 24,4 26,0 27,4 35 °C 20,4 22,9 25,1 27,1 29,0 30,6 32,1 40 °C 23,0 26,0 29,0 31,5 33,5 36,5 38,0
20% 30% 40% 50% 60% 70% 80%
Relative humidity of the inlet air
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Tr Tbu Ta
12
4 AIR PSYCHROMETRIC CHART
The performance of an evaporative cooling system varies ac­cording to the physical conditions of the treated air, they depend
Figure4.1 Air psychrometric chart - legend
7
8
9
on the saturation eciency of the evaporative pack and can be obtained using air psychrometric chart.
1
2
3
11
6
A
4
5
1 Dry temperature 2 Deviation of the enthalpy 3 Relative humidity 4 Specic humidity 5 Specic volume
6 Wet temperature 7 Enthalpy 8 Saturation curve 9 Pole 10 Dry bulb temperature
10
11 Specic humidity 12 Thermal factor Ta Ambient temperature Tr Dew temperature Tbu Wet bulb temperature
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Tbs -10 -5 0 5 10 15 20 25 30 35 40 45 50
125 130 135 140 145
US [g/kg]
Design manual AD evaporative coolers
Figure4.2 Air psychrometric chart
34
32
30
120
115
110
105
100
28
26
100
95
90
85
80
22
20
18
16
14
12
10
8
6
4
2
24
90
75
70
70
80
65
60
55
50
45
50
60
40
35
30
25
30
40
20
15
10
Entalpia [kJ/kg]
5
20
0
-5
0
10
-10
It should therefore be specied that the evaporative cooling sys­tem provides a dierent degree of comfort to the environment as the physical conditions of the outdoor air change, and cannot guarantee constant and predened temperature and humidity conditions.
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5 THE EVAPORATIVE COOLER
The AD evaporative cooler is an appliance powered by electricity and mains water, which is installed on the roof or on the exter­nal wall or in correspondence with a window of the room to be ventilated and cooled. Ducts and air diusers are connected to it to distribute the cooled air in the room. The coolers are equipped with an external load-bearing struc­ture in ABS that guarantees protection from the weathering and a particular lightness, a very important aspect in relation to the limited load-bearing capacity of the roofs and walls of the buildings. The coolers are equipped with:
▶
low consumption electric fans
▶
water loading system with solenoid valve
▶
water distribution system with electric pump
▶
evaporation panels with high saturation eciency
▶
automatic water drainage system
▶
automatic periodic cleaning for the whole hydraulic circuit and the evaporating panels
▶
electronic command and operation panel
5.1 EVAPORATIVE COOLER OPERATION
Each cooler is equipped with a remote electronic control and operation panel for adjusting the air speed and for choosing the various functions:
▶
ventilation only
▶
ventilation and cooling The panel contains the logic unit for setting the functions nec­essary for the operation of the cooler, including the periodic washing of the evaporating panels and the washing and the drainage at the end of the cycle; these functions are essential for maintaining high performance over time and for preventing the proliferation of bacterial forms. Depending on the remote control chosen and used, it is also possible to adjust the microclimate in each zone according to the real needs of the time and season or according to the per­sonal perception of the operator directly concerned, thanks to the weekly and daily timer, to the maximum percentage of rela­tive humidity required and to the fan speed.
▶
When the machine is started, the water discharge valve (nor-
mally open) closes, the water loading valve opens and allows
water to enter the collection tank. A level switch limits the
water load up to the amount required for the cooling cycle.
▶
An electric recirculation pump lifts the water up to the dis-
tributor circuit which wets the evaporating panels.
▶
The electric fan starts and sucks in the outside air through
the wet evaporating panels and feeds it into the room
through the delivery outlet.
▶
The water that evaporates during the cycle is replenished on
command of the level switch of the collection tank.
▶
By acting on the control panel, it is possible to interrupt the
cooling function and operate the appliance in ventilation
mode only, granting in any case the required air renewal.
▶
By acting on the fan speed regulator it is possible to custom-
ize the ow and the quantity of air introduced into the room.
There is an automatic washing cycle every 3 hours (standard): the appliance suspends its evaporation cycle for a few minutes, the water contained in the tank is discharged and replaced with clean water that is circulated through the evaporative packs in order to wash out the residues of mineral salts and any other deposits. The repetitiveness of these washes prevents the crystallization of minerals and other elements on the evaporative packs and throughout the circuit, guarantees a long life and maintains a high saturation eciency. Each time the unit is switched o, a nal wash cycle is performed. At the end, the cooler discharges all the water contained in it to prevent water stagnation from causing the development of bacterial forms and the formation of limescale deposits.
Figure5.1 Cellulose evaporating panels
Figure5.2 Recirculation pump and water distribution system
Figure5.3 Automatic washing and emptying device
5.2 DESCRIPTION OF THE AUTOMATIC
CLEANING SYSTEM
The cooler is equipped with an automatic washing system for the evaporative pack and the water collection tank which, at programmable intervals, is automatically activated to maintain a high level of cleanliness and saturation eciency.
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Figure5.4 Water drain device
5.3 ROUTINE MAINTENANCE
Routine maintenance of the evaporative cooler is limited to end­of-season cleaning, which includes washing the water distribu­tion circuit, the evaporative packs, the recirculation pump and the water collection tank. In the winter season it is necessary to drain all the water con­tained in the supply system to avoid damage caused by freezing. The cooler can be covered with a winter cover (optional OCPR003) to protect it from weathering and to prevent the in­trusion of cold air into the room. Every three to four years we recommend replacing the evapo­rating panels.
6 DESIGN OF A COOLING AND VENTILATION SYSTEM
The purpose of the system is to cool and ventilate a large room during the hot seasons, lowering the temperature of the indoor air compared to the outdoor air and making the necessary air renewal to improve the microclimate inside the room. The lowering of the internal temperature will help to neutralize the heat contributions coming from the structures of the build­ing, from the sun's rays, from the process plants inside. Air renewal will help to dispose of the exhausted air and any fumes, vapours, smells or other aeriforms, often harmful to the health of workers. The cooling eciency is not only related to the eciency of the appliance, but also to the design of the ductwork and the instal­lation. Insulated ceilings will decrease the internal temperature signicantly compared to non-insulated ceilings. The same con­cept is applicable for air ducting. In order to size the plant we must take into account four funda­mental elements:
1. the outdoor summer design conditions
2. the installation height of the air diusers in the room
3. the number of air renewals required according to the type of
activity carried out in the room
4. evacuation of exhaust air
6.1 OUTDOOR SUMMER DESIGN
CONDITIONS
As already seen, the AD evaporative cooler is a system that works
dynamically and operates on the basis of a natural principle: it introduces large quantities of external and cooled air into the room and expels the exhausted hot air through doors, windows and other exhaust openings. The cooling of the air taken from the outside and introduced into the room is a function of the outdoor conditions (Table
3.1
p.5
).
6.2 AIR DIFFUSERS INSTALLATION HEIGHT
IN THE BUILDING
The air coming from the coolers tends to descend towards the oor and to push up the warmest one. The area of inuence that interests us is the one where people work, so the volume to be cooled is that between the oor and the height of diusion of the cooled air. To allow normal operation, the air diusers must be installed no less than 4 metres above the ground and, in order not to unnec­essarily cool the upper part of the room, it is recommended not to exceed 6 metres in height. It should be noted that the higher the installation height of the diusers, the lower the cooling eect near the oor. The volume to be treated is therefore equal to the surface area of the area concerned multiplied by the height from the ground of the diusers.
Figure6.1 Positioning of diusers and extractors
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6.3 NUMBER OF AIR RENEWALS REQUIRED
DEPENDING ON THE TYPE OF ACTIVITY IN THE BUILDING
Once the volume to be cooled has been identied, it is necessary to multiply it by the number of air renewals per hour required ac­cording to the type of activity. The quantity of air to be supplied to the room is thus obtained to grant the required air renewal and the cooling of the environment. Table 6.1
p.10
indicates the minimum suggested air renewal
for dierent activities.
Table6.1 Air renewal according to the activity
Activity Air renewal
Oces and shops v/h 8 ÷ 10 Light processing (warehouses, storage areas) v/h 10 ÷ 15 Medium processing (production and assembly
areas) Heavy processing (presence of ovens, equip-
ments with moderate heat development) Extreme conditions (foundries, furnaces with
high heat generation)
v/h = volumes/hour.
v/h 15 ÷ 20
v/h 20 ÷ 30
v/h 30 ÷ 40
6.4 EXHAUST AIR EVACUATION
Once the quantity of air to be supplied to the room has been identied, the size of the openings required for exhaust air ex­traction must be calculated. The system involves the introduction of cooled air into the room and the extraction of at least 80% of it through natural openings or forced extraction systems. The extraction of at least 80% of the air introduced is essential to grant the planned renewals, to grant the cooling eect and to avoid an increase in the percentage of relative humidity in the room.
The extraction of a quantity of air slightly lower than the one in­troduced (but not less than 80%) allows to keep the cooled room in a slight overpressure compared to the outside, preventing the outside hot air from re-entering the room through the natural openings. The air produced by the coolers contains a percentage of relative humidity higher than that of the external air and that of the air in the building: this is precisely the characteristic that produces the cooling eect. For this to be eective, however, it must pass through the room and then leave. In this way, the percentage of relative humidity in the room will not increase and the cooling eect will be granted. To extract the exhaust air, natural openings of about 1 m2 per 1000 m3 of air are required. If it is necessary to evacuate 10000 m3 of air it will take about 10 m2 of natural openings. It is important that the openings (windows, doors, gates, sky­lights, ...) are not concentrated in a single position or only on one side of the room, but that they are distributed throughout the building to allow ventilation and cooling of the whole room and not only of a part of it. The best result is obtained when there are also openings on the roof, such as skylights or natural extractors: through these open­ings it is possible to evacuate the mass of hot air that is under­neath the roof and usually stays there for a long time.
If the natural openings are larger than the amount re­quired to evacuate the exhausted air, or if the extracted air ow rate is greater than 80% of the supplied air, there is a risk of attracting more hot air from outside and re­ducing the cooling eect.
If there are already forced extraction systems in operation in the room, their capacity must be taken into account and subtracted from the calculation of the necessary openings. It is necessary to ensure that there is a correct balance between the amount of air entering and leaving the room.
7 CHOICE OF MODELS AND NUMBER OF COOLERS TO BE INSTALLED
The choice of models and the number of AD coolers to be in­stalled depends on the customer's needs, on the dierent possi­bilities of positioning the coolers and the air ducts, considering that the installation quota of the air diusers should not exceed 6 m from the ground. The ideal choice is to install the coolers on the roof of the build­ing and enter with the ducts through the skylights. The quantity of coolers to be installed depends on the calculat­ed intake air ow rate: Number of coolers = total air ow (m³/h) / air ow of the selected coolers (m³/h).
It is important to distribute the air in the room as evenly as possible.
7.1 AVAILABLE RANGE
The AD evaporative coolers are available in two models, which dier in the maximum air ow that can be delivered:
▶
AD14 with air ow up to 13000 m³/h
▶
AD20 with air ow up to 20000 m³/h Three dierent versions are available for each model, two of which are equipped with an independent basic (ECO) or ad­vanced (EVO) remote control for each unit, and the third (SC) is suitable for the centralised management of a system composed
of a maximum of 30 units, to be associated with a centralised control system, supplied by Robur. The three versions can be summarized as follows:
▶
AD14/AD20 ECO: equipped with the basic ECO remote con­trol (Paragraph 10.1
▶
AD14/AD20 EVO: equipped with the advanced EVO remote control (Paragraph 10.2
▶
AD14/AD20 SC: without individual remote control, but de­signed for a centralised control (Paragraph 10.3
p.13
).
p.13
).
p.14
7.2 SIZING EXAMPLES
Surface area of building to be cooled: 2000 m² Building height: 8 m Height of the cooled air diusers: 5 m Type of activity carried out inside: medium processing Expected air renewal: 15 v/h Net volume to be cooled: 2000 x 5 = 10000 m³ Total required air ow: 10000 x 15 = 150000 m³ Single cooler air ow rate: 20000 m³/h (model AD20) Number of coolers to be provided: 150000/20000 = 8 AD20
7.3 EVAPORATIVE COOLER INSTALLATION
The installation works are very simple and consist of clamping the machines in the chosen position, connecting the ducts and
).
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1
2
4
1 2
3 4
5
air diusers, the construction of the water supply and drainage network and the power supply network and the connection of the electronic control. The following Figures show installation examples.
Figure7.1 Installation example
≥ 0,4 m
6
≥ 1 m
3
5
1 Galvanized or stainless steel chains for xing the channels to the ceiling 2 Duct with anges and neoprene gaskets 3 2-way diuser with adjustable ns 4 Wall 5 90° curve with anges and neoprene gaskets 6 Support frame
Figure7.2 Installation example
6
7 8
1 Skylight 2 Coverage 3 Stainless steel brackets 4 Duct with anges and neoprene gaskets 5 6-way diuser with adjustable ns 6 Dowels to x the brackets to the ceiling 7 Screws to x the duct to the brackets 8 Galvanized or stainless steel chains for xing the channels to the ceiling
Figure7.3 Installation example
1
2
3
1 Support frame 2 Duct with anges and neoprene gaskets 3 Galvanized or stainless steel chains for xing the channels to the ceiling 4 6-way diuser with adjustable ns 5 45° curve with anges and neoprene gaskets 6 Duct with anges and neoprene gaskets
8 ELECTRICAL AND WATER SUPPLY NETWORK
5
6
4
8.1 WATER SUPPLY NETWORK
The water necessary for the cooler operation can be drawn di­rectly from the local water mains. No kind of softening treatment is necessary as the cooler pro­vides for periodic programmed cleaning of the internal circuits to avoid the formation of limescale deposits and the crystalliza­tion of the mineral salts contained in the water.
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AD evaporative coolers
If you feel you have particularly hard water, you can program more frequent washes. It is advisable to install the water supply network inside the building to protect it from freezing in the winter season and from the sun's rays during the summer; otherwise, it is recom­mended to install a suitably insulated pipe.
The water supply system must grant a minimum ow
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4
rate of 7 l/min for each unit at a pressure of 1,5÷3 bar (maximum allowed pressure: 6 bar).
The distribution network must be equipped with a suitable lter to prevent the passage of solid elements, such as sand and dirt. The AD evaporative cooler is equipped with a water supply con­nection located in the lower part of the external structure (detail A Figure 12.1
p.17
and 12.2
p.18
). It is recommended to install an isolation valve at the inlet of the unit and make the connection to the water supply with a exible stainless steel pipe.
It is recommended to provide for the possibility of
Figure8.1 Electrical wiring diagram
V+
V-
L1 L2
M/S
X
A1
2
emptying the entire water supply system before the start of the winter season to avoid damage due to freezing.
The evaporative cooler is equipped with a sleeve located on the bottom of the external structure for the connection of the water discharge pipe of the periodic washes. Refer to Table 12.1
p.17
for water connection dimensions and
water consumption.
8.2 ELECTRICAL SUPPLY NETWORK
The supply voltage of AD appliances is 230 V - 50 Hz. The electrical system must be constructed according to the reg­ulations in force in the country where the machine is installed.
1 Onboard electrical panel 2 Power supply 230 V - 50 Hz 3 Remote control 4 20 AWG 5x0,5 mm2 shielded cable 5 Do not connect A1 Main switch onboard the appliance BRO Brown WHI White GRE Green YEL Yellow GRY Grey
YEL
WHI
GRE
BRO
MAX 25 m
The cooler must be connected to the selected remote control (Paragraph 10
9 EVALUATION OF THE EFFECTIVE EFFICIENCY OF THE COOLERS
p.13
), which is normally installed in the cooled
9.1 WATER CONSUMPTION IS SYNONYMOUS
WITH EFFICIENCY
These appliances base their operating principle on the ability to evaporate water using the heat contained in the air treated by the cooler. In other words, the higher the water consumption, the greater the cooling eect. Using the parameters of Table 9.1 for every liter of water evaporated from 1000 m³ of air, there will be a reduction in air temperature of about 2 ° C.
Table9.1 Air and water parameters
Latent water evaporation heat J/kg 2260000 Water density kg/m³ 997 Air specic heat J/kg @40 °C 1005,5 Air density kg/m³ 1,14
p.12
GRY
5
we can estimate that
A3
V-
V+
L2 L1
room.
In the case of an AD14 cooler we have:
▶
air ow: 13000 m³/h
▶
water consumption: 43 l/h
▶
temperature gradient of the outlet air: 6,5 °C In general, if you want to make a comparison with other types of coolers, the lower the declared water consumption, the lower the cooling eect that can be obtained.
9.2 EVAPORATIVE PACKS CROSSING SPEED
The crossing speed of the evaporative packs of the treated air also contributes to the eciency of the appliance as a whole. In fact, the producers of the exchange packs usually provide a graph in which it is possible to deduce the exchange eciency in relation to the air speed (and therefore the air ow rate of the cooler): the higher the speed, the lower the exchange eciency (Figure 9.1
p.13
).
12
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5
A
B
Figure9.1 Evaporative pack saturation eciency diagram
Moreover, if the crossing speed approaches 3 m/s, the droplets of water present on the edge of the evaporative packs may be subject to entrainment, with the consequent introduction of wa-
D
=
1
5
0
m
m
90
1
0
0
ter into the cooled room. In the case of an AD14 cooler we have:
▶
Net exchange area: 2,7 m²
▶
air ow: 13000 m³/h
▶
speed: 1,33 m/s
The crossing speed designed for the Robur AD units allows a
80
70
60
A Saturation eciency (%) B Air speed (m/s) The grey area shows the conditions in which condensation forms.
7
5
5
0
3210.5
4
good exchange eciency of the evaporative pack and a su­ciently low speed to avoid dragging phenomena of water drop­lets in the cooling air.
10 CONTROL AND REGULATION SOLUTIONS
The evaporative coolers are available in three dierent versions, two of which are equipped with an independent basic (ECO) or advanced (EVO) remote control for each unit, and the third (SC) suitable for the centralised management of a system composed of up to 30 units, to be associated with a centralised control sys­tem, supplied by Robur. The three versions can be summarized as follows:
▶
AD14/AD20 ECO: equipped with the basic ECO remote con­trol (Paragraph 10.1
▶
AD14/AD20 EVO: equipped with the advanced EVO remote control (Paragraph 10.2
▶
AD14/AD20 SC: without individual remote control, but de­signed for a centralised control (Paragraph 10.3
p.13
).
p.13
).
p.14
). The SC versions can be equipped with two dierent types of centralized control:
▶
centralized control via SC bus
▶
centralized control via SC bus with Modbus interface for any external supervision system (e.g. BMS)
10.1 ECO BASIC REMOTE CONTROL
Figure10.1 ECO basic remote control
Table10.1 ECO control technical specications
Mounting on the wall or on an electric box mod. 503 Frontal protection IP00
Operating conditions Relative environment
humidity Connections Display 4 digits display + 10 icons + LED
Ambient temperature -10/+60 °C Storage temperature -20/+70 °C
20÷80%, non condensing screw terminals for wires with a maximum cross-sec-
tion of 4 mm² and 2,5 mm²
The features of the ECO basic remote control are:
▶
Turning the appliance on and o.
▶
Cooling/ventilation selection.
▶
Ventilation speed selection (3 levels).
▶
Diagnostics of any faults.
Refer to Figure 8.1
p.12
for the wiring diagram.
10.2 EVO ADVANCED REMOTE CONTROL
Figure10.2 EVO advanced remote control
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Table10.2 EVO control technical specications
Enclosure plastic box, dimensions: 180x150x65 mm Data storage on EEPROM memory Frontal protection IP54
Operating conditions Relative environment
humidity Connections Display 4 digits display + 10 icons + LED Inputs
Ambient temperature -10/+60 °C Storage temperature -20/+70 °C
20÷80%, non condensing screw terminals for wires with a maximum cross-sec-
tion of 4 mm² and 2,5 mm²
1 input for temperature and humidity digital sensor (0÷99 rH, precision at 25 °C: ± 3% FS).
The features of the EVO advanced remote control are:
▶
Automatic/manual operation selection.
▶
Cooling/ventilation selection.
▶
Automatic or manual selection of the ventilation speed (3 levels).
▶
Room temperature detection by integrated thermostat.
▶
Ambient humidity detection by integrated humidistat.
▶
Automatic operation based on the setpoint.
▶
Daily programming of the operating time schedule.
▶
Diagnostics of any faults. The EVO control, compared to the ECO, can provide automat­ic control of the unit, thanks to the temperature and humidity probes, and can adjust the fan speed accordingly to the 3 levels available. With the EVO command it is also possible to set a daily time schedule, as it is also possible to set the cooling or ventila­tion only mode.
The automatic ventilation operating mode can only be
selected if the temperature and humidity probe is cor­rectly connected to the control.
Refer to Figure 8.1
p.12
for the wiring diagram.
10.3 CENTRALIZED CONTROL
Figure10.3 OCDS009 network card
Figure10.4 OCDS010/OCDS011 centralized control
This solution allows to centrally manage plants composed of several units (up to a maximum of 30). The features of the centralized control are:
▶
Displaying and setting the date and time of network devices.
▶
Displaying of temperature and humidity measured by net­work devices.
▶
Displaying and changing of temperature and relative hu­midity setpoints for each individual network device.
▶
Displaying and change network device parameters.
▶
Turning each single network device on and o.
▶
Daily programming of the operating time schedule of the whole system.
▶
Automatic/manual/o operation selection for each individ­ual network device.
▶
Cooling/ventilation selection for each individual network device.
▶
Diagnostics of any faults. In this case, it is not necessary to provide a remote control (ECO/ EVO) for each cooler, but it is sucient to equip each one with a network card (optional OCDS009), which is equipped with a temperature and humidity sensor, which also communicates with a centralised electrical control panel via SC bus (optional OCDS010) and possibly also with an external supervisor (for ex­ample a BMS) via Modbus (optional OCDS011).
Table10.3 OCDS009 network card technical specications
Power supply 230 V AC ± 10% Consumption 5 VA
Enclosure Data retention on EEPROM memory
Protection IP54 Operating conditions Relative environment
humidity Connections
Inputs
plastic box, dimensions: 180x150x65 mm plus humidity sensor
Ambient temperature -10/+60 °C Storage temperature -20/+70 °C
20÷80%, non condensing Screw terminals for cables with a maximum section of
2,5 mm2 1 input for temperature and humidity digital sensor
(0÷99 rH, precision at 25 °C: ± 3% FS). 2 0-10 V inputs:
• I1 = temperature, 0÷50 °C max, precision 5%
• I2 = humidity, 0÷100 rH, precision 5%
14
Table10.4 General electrical control panel (OCDS010/OCDS011)
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technical specications
Power supply 230 V AC ± 10% Operation eld -50/+150 °C Consumption 7 VA Enclosure plastic box, dimensions 300x220x120 mm Mounting on the wall Protection IP00 front panel
Operating conditions Relative environment
humidity Connections Display Backlit LCD
Inputs 3 inputs for PTC probe Outputs ALARM SPTS relay
Serial communication
Ambient temperature -10/+50 °C Storage temperature -20/+70 °C
30÷80%, non condensing Screw terminals for cables with a maximum section of
2,5 mm2
1 RS-485 serial port for SC bus. The maximum network length is 1000 m 1 TTL serial interface Only for OCDS011: 1 RS-485 serial port for Modbus
Figure10.5 Connection of network cards to the central control panel
To use this control mode, it is essential that each cooler (up to a maximum of 30) is equipped with the OCDS009 network card and that they are connected as an alternative to either the OCDS010 or OCDS011 control panel (the latter if connection to the Modbus network is required). Figure 10.5
p. 15
below shows the wiring diagram for con­necting the network cards to the control panel (OCDS010 or OCDS011).
1
1 General electrical control panel (OCDS010/OCDS011) 2 Electronic board with temperature and humidity sensor (OCDS009)
2 3
3 Electronic board with temperature and humidity sensor (OCDS009)
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495
11 DIFFUSION PLENUMS
For a more homogeneous diusion of the cooled air in the room, diusion plenums are available as an option:
11.1 DIMENSIONS
Figure11.1 4-way plenum ODFF002 dimensions
630
600
100
105
250
600
650
805
▶
4-way diusion plenum for AD14
▶
6-way diusion plenum for AD20
Ø8
600
630
660
Figure11.2 6-way plenum ODFF003 dimensions
590
1185
30
Ø8
808.3
250
1630.7
660
630
590
600
1532.1
100350
450
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630
D
1150
1150
12 TECHNICAL DATA AND DIMENSIONS
12.1 TECHNICAL CHARACTERISTICS
Table12.1 Technical characteristics
AD14 AD20
Installation data
at maximum speed m³/h 13000 20000
Air ow
fan type - assiale maximum useful pressure head Pa 80 water consumption l/h 43 (1) 64 (1)
Water inlet
Water drain
Humidifying panel
Dimensions
Weight
Electrical specications
Power supply
Electrical power absorption nominal kW 1,10 1,80 maximum power consumption A 4,8 7,0
(1) Test conditions: outdoor temperature 33 °C, relative humidity 60%.
at average speed m³/h 9700 15000 at minimum speed m³/h 6500 10000
type - M thread “ 3/8 type - M diameter (Ø) mm 60 surface m² 2,7 3,4 thickness mm 100 saturation eciency % 88 width mm 1150 1650 depth mm 1150 height mm 1050
Air delivery outlet
width mm 600 1185
height mm 600 590 weight kg 67 120 in operation kg 88 146
voltage V 230 type - single-phase frequency Hz 50
12.2 DIMENSIONS
Figure12.1 AD14 dimensions
A Water inlet 3/8" M B Water drain 60 mm M C Electrical panel
D
C
A
170
280
38
555
320
660 600
B
209
65
595
600
660
630
D-D
1050
A
243
86
C
117
B
80
110
217112
440
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1650
Figure12.2 AD20 dimensions
1150
1050
D
C
592.5 592.5
825
590
660
A
1245 1185
1215
150
A Water inlet 3/8" M B Water drain 60 mm M C Electrical panel
12.3 INSTALLATION EXAMPLES
Figure12.3 Installation example
261.5
D
B
530
825
620
189
130
205
C
A
B
80
195
280
85170
530
128
165
D-D
Figure12.4 Installation example
18
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Figure12.5 Installation example
Figure12.6 Installation example
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Robur mission
Robur is dedicated to dynamic progression in research, development and promotion of safe, environmentally-friendly, energy-eciency products, through the commitment and caring of its employees and partners.
07/06/2019
19 MED SDC 008
Code: D-MNL053EN
Robur S.p.A. advanced technologies for climate conditioning via Parigi 4/6 24040 Verdellino/Zingonia (BG) Italy +39 035 888111 - F +39 035 884165 www.robur.it [email protected]
Revision: A
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