Middle East & Africa Air Handling Units - Hisense · Middle East & Africa Air Handling Units ... Special attention is given in maintenance ... - The possibility of completely dismantling
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Middle East & AfricaAir Handling UnitsAHU Series 50 Hz
4007, AA1, Mazaya Business Avenue, Jumeirah Lake Towers, Dubai, UAE Office : 00971-4-5906900 Fax : 00971-4-4219871 htttp://global.hisense.com
Quality Policy 04
Introdcution 05
Design 06
Coil Section 08
Bag Filtrer Section 09
Mixing Box Section 10
Heat Recovery Section 10
Plenum 12
Fan Section 14
Coil Section 15
Filter Section 16
Mixing Box Section 17
Heat Recovery Section 18
Fan Charts 21
Coil Capacities 26
Capacity & Water Pressure Drop Chart 28
Operational Examples 43
AIR HANDLING UNITS CATALOG Middle East & Africa
02 03
AHU Series with 50 Hz
Quality PolicyWe set ambitious objectives for our people and the company as a whole and we define ,establish and promote high standards of performance for our products, systems and services
We assure in all phases of our operations that the products the systems and the services meet the specifications and expectations of our customers and/or our partners in the business.
We work and act in such a way that the task we per- form as individuals or corporate entity, safeguards our interests and serves to attract more business opportunities
IntroductionHisense Air Handling Units are of modular design, in 15 models ,with air flow from 2250 m3/h(1325 cfm) up to 77800 m3/h( 45760 cfm).
The modular design permits any possible combination in order to meet the customer demand.
With calculations made with special software and according to EU- ROVENT AMCA,ASHRAE and AHRI standards, trouble-free operation with low operating cost is guaranteed for many years
Special attention is given in maintenance issues like
• Easy access of fan and motor and easy replacement and tensioning of belts
• Removal of the drift eliminator from the unit for easy cleaning and also coil access for cleaning
• Easy bag filter removal from the dirty side of the unit ,either in sliding or in fixed frame ,according to space available
• Easy prefilter removal through sliding channels e.t.c
AIR HANDLING UNITS CATALOG Middle East & Africa
04 05
CASING
The frames are made of extruded heavy aluminum profiles, anodized for extra anticorrosion protection and with THERMAL BARRIER ( a full peripheral pvc thermal break is incorporated to ensure no thermal bridge occurs from any internal to external surface ) The profiles are connected by means of special plastic corner pieces, to form the AHU sections. (pentapost design) This type of construction has the following features:
- Excellent mechanical strength- Flexibility of construction- Perfect appearance and dimensions precision- Quick and precise installation of interior components- The possibility of completely dismantling the unit in case of diicult access and re- assemble on site at minimum time and cost
The panels are of the double-skin type with a rigid insulation layer consisting of a factory applied polyurethane layer injected between the panels, having a density of 38-40 kg/m3. This type of material has excellent heat insulation and noise reduction properties and ads extra mechanical strength and rigidity to the panels and meet NFPA-90A Flame speed and Smoke generation requirements.
The panel thickness can be either 25 mm or 50 mm on the same aluminum profile. The overall heat transfer coeicient U(w/m2.K) is calculated from the formula
Where h0 =25 w/m2.k for air outside the unithi=8 w/m2.k for air inside the unitk=0.021 w/m.k the thermal conductivity of the polyurethane foam t=0.025 (25 mm panel) or 0.05(50 mm panel).
So the heat transfer coeicient for 25 mm panels is : U =0.73 w/m2 K which is category T2 according to EN 1866and the heat transfer coeicient for 50 mm panels is : U =0.39 w/m2 K category T1 according toEN1866 The insulation factor kb(cold bridge factor) is defined by the following formula
Where ts =the lowest external surface temperature of the unit casing (35 C for GAH units) ti=average temperature of the air inside the unit (11 C in most cases for GAH units)
te=average ambient temperature 46 CBased on the above conditions the kb factor is equal to 0.685 and is in the category TB2 according to EN1866
The construction of the panels is made with G90 galvanized sheet metal ,1mm thickness outer skin and painted with RAL9002 polyester epoxy paint, and 0.6 mm inner skin which optionally can be made from SS (304 or316) sheet metal.
The minimum noise reduction according to DIN 52210 is as given in the following table:
AIR HANDLING UNITS SECTION DETAILS
The proper operation of the AHU is achieved by combining structural modules of dierent function each one. The modules of the AHU’s are
• FAN SECTION
• COIL SECTION
• BAG FILTER SECTION
• MIXING BOX SECTION
• HEAT RECOVERY SECTION
• PLENUM SECTION
The unit is selected and calculated for his performance with the aid of a specifically designed for that purpose software.All the sections are equipped with G90 sheet metal base ,150 mm height ,as a standard feature. Rain canopy can also be installed as an optional feature.Analytically below are information for the various sections (modules).
FAN SECTION
The fan capacities are verified according to AMCA 210.The fan motors are of the totally enclosed fan cooled type (TEFC) with class F insulation. Transmission is carried out via V-belts and pulleys. The pulleys are selected with tapper lock bush facility for easy installa- tion and maintenance. The fan- motor assembly is placed on a common base and is elastically suspended inside the unit, thus eliminating the need of external vibration isolators.
The fan outlet is connected to the unit panel by means of a special canvas fabric, to avoid any transmission of vibration to the unit panel.
Access door is provided for maintenance purposes with the option of sight glass to be fitted on the door. The door is suspended on high quality aluminum hinges and has locks operating with tool as per ma- chinery safety directive 2006/42/EC. Optional features for the fan sec- tion are.
• Belt guard
• External power switch for the motor with padlock capability
• VFD
• Light with external switch
• Spring type isolators instead of rubber type which is the standard.
Octave bandMidfrequencySoundattenuation(25mm) dbSoundattenuation(50mm) db
Which gives 31.6 db noise reduction for 25 mm panel and 36.4 db noise reduction for 50 mm panel
DESIGN
AIR HANDLING UNITS CATALOG Middle East & Africa AHU Series with 50 Hz
The chilled water coils are manufactured from seamless copper tubes 3/8” O.D and 0.35 mm thickness, with aluminum fins with thickness from 0.12 mm up to 0.15 mm depending on the fpi used. The standard for our calculations is 12 fpi and 0.12 mm aluminum fin thickness. The fins can either be mil finish as stand- ard or anticorrosion coated optional.Coil headers are made of seamless steel tubes to DIN 2440 and have parallel male threads according to DIN 2999.Optionally the headers can be made from seamless copper pipe according to ASTM 280 with male threaded bronze fittings. The coil casing is made of heavy gauge gal- vanized steel
All coils are factory tested at dry air pressure of 30 bar (441 psi) under warm water.
The capacity of the coil is software calculated according to ARI 410 procedure and from an appropriate software.
The drain pan is fabricated of G90 1.5 mm thickness sheet metal ,epoxy painted as standard or by SST (304 or 316),1.2 mm thickness as an option. . The drain pan has a threaded connection 3/4 “ BSP for the proper siphon to be connected.
When the face velocity on the coil is above 2.5 m/s a droplet eliminator is installed in the coil section.
Theoretically the need of eliminator ,depends on the sensible heat factor of the coil and the maximum ve- locity for various SHF as given in the table below
The eliminator is made from a special plastic profile secured on an epoxy painted sheet steel frame.
The eliminator assembly can be removed from the unit through an access door ,in order to facilitate the maintenance and cleaning of the coil
This section is equipped with bag filters type EU8 as per EN779 ,635 mm long, as standard .Other type of bag filters can be installed optionally. In this section can also be installed type EU4 prefilters as per EN779.
The final permissible pressure drop for EU8 bag filters is 450 pa while for EU4 prefilters the limit is 250 pascal,as per EN779.
Dierential pressure manometers can be installed optionally to indicate the above pressure drop.
The calculation of the unit is made with pressure drop 300 pa for the bag fil- ters and 150 pa for the prefilters.
The frame of the bag filters as a whole assembly can be, either by sliding removable ,or fixed in the unit, whereby an extra space is given for filter removal which is always done in the dusty air side of the unit.
The frame of the prefilters is fixed in the unit and the filter renewal is made by sliding them out .
EUROVENT 4/5 STANDARD
COIL SECTION BAG FILTER SECTION
AIR HANDLING UNITS CATALOG Middle East & Africa
BAG FILTERS
40-%60
60-%80
80-%90
90-%95
>%95
<%65
65-%80
80-%90
>%90
PREFILTERS
AHU Series with 50 Hz
08 09
AIR HANDLING UNITS CATALOG Middle East & Africa
The mixing box can either be single or double type depending on the operational design of the unit. The dampers which are installed in the unit are selected with maximum velocity 5 m/s ,when the full air flow is passing through each of them.The operation of the dampers is made through independent handles for each of them. As an option the movement of the dampers can be made motorized as per customer request.
MIXING BOX SECTION
SINGLE MIXING BOX DOUBLE MIXING BOX
HEAT RECOVERY SECTIONThis section is for air to air plate heat exchangers or rotary heat exchangers to be installed.In case of plate heat exchanger ,drain pan epoxy painted is installed in both supply and return side of the unit, whereby face and bypass damper can be installed optionally in the supply section of the unit.The calculation of the performance of the heat exchanger is made with special software from the manu- facturer (e.g Hoval, Heatex e.t.c) and the selection is made to a maximum face velocity on the exchanger 4 m/s.
AIR TO AIR PLATE HEAT EXCHANGER
AHU Series with 50 Hz
10 11
Models and Quick Selection Table AHU’s Quick Selection Chart
PLENUMThis section is for various purposes according to the operational design of the AHU and a variety of items like steam humidifiers, laminar humidifiers, HEPA filters e.t.c can be installed.
12 13
HAH 1416-450
4 ROWS COIL
6 ROWS COIL
8 ROWS COIL
m3/h AIR FLOW
m3/h AIR FLOW
m3/h AIR FLOW
m3/h WATER FLOW
m3/h WATER FLOW
m3/h WATER FLOW
kw
kw
kw
kpa
kpa
kpa
HAH 1616-510
4 ROWS COIL
6 ROWS COIL
8 ROWS COIL
m3/h AIR FLOW
m3/h AIR FLOW
m3/h AIR FLOW
m3/h WATER FLOW
m3/h WATER FLOW
m3/h WATER FLOW
kw
kw
kw
kpa
kpa
kpa
Capacity & Water Pressure Drop Chart Capacity & Water Pressure Drop Chart
40 41
HAH 1620-650 4 ROWS COIL
6 ROWS COIL
m3/h AIR FLOW
m3/h AIR FLOW
m3/h WATER FLOW
m3/h WATER FLOW
kw
kw
kpa
kpa
Capacity & Water Pressure Drop Chart Operational Examples