TECHNICAL MANUAL HEAT RECOVERY UNITS URE SERIES

Transcription

1 TECHNICAL MANUAL HEAT RECOVERY UNITS URE SERIES

2 SUMMARY 1. GENERAL FEATURES 2 2. VERSIONS AND COMPONENTS 2 3. ORIENTATIONS 3 4. NOMINAL TECHNICAL DATA 4 5. AVAILABLE ACCESSORIES 5 6. FAN CHARACTERISTICS RECUPERATORS PERFORMANCES DIMENSIONS GENERAL FEATURES The new URE heat recovery units series has been designed for ambiences with frequent air change-over, where it is necessary to recover part of the heat which would otherwise be expelled in the exhaust air flow. Proposed in 8 models, with nominal flow rates from 290 to 4000 m3/h, the URE heat recovery units are suitable for installation in false ceilings. OPERATING LIMITS Thermal fluid: water Water temperature: +5 C +85 C Air temperature: -20 C +43 C Supply voltage: +/- 10% Max. operating pressure: 10 bar The unit is not suitable for operation in ATEX areas (or similar). 2. VERSIONS AND COMPONENTS Constructive versions URE heat recovery unit with sandwich panels. Constructive components URE series for the renewal of the air and recovery of the exhaust heat, characterised by: - bearing frame in aluminium profiles and closing panels in prepainted steel (outside) and galvanised steel (inside) - thermo-acoustic insulation with high density polyurethane foam, fire reaction class 1 (according to DM 26/6/84); - mechanical coupling by means of steel screws and highefficiency aluminium rivets - accessibility to all the internal components ensured on all sides of the unit - undulated synthetic filters with galvanised steel frame and metallic net; filtrating class G3; - air-to-air heat recovery unit (category 1 according to EN 308) with high efficiency (up to 60%), static cross-flow type, made up by aluminium plates sealed in order to avoid contamination between the exhaust air and the supply air flows, installed on slides to allow for an easy extraction and cleaning - condensate drain pan, prepainted and resistant to corrosion, equipped with disassembling system for the extraction of the recuperator; bottom condensate discharge; - double inlet centrifugal fan with forward-curved blades, balanced statically and dynamically with a directly-coupled motor, single-phase with 3 speeds (1 speed, three-phase YD) according to the models; - control panel complete with relay card for the control of the fans; Unit compliant with the safety requirements according to EN , EN and electromagnetic compatibility according to EN , EN , EN , EN ; - Fan bodies assembled on anti-vibration dampers; - Fresh and exhaust air fans, double-inlet centrifugal type, easy to extract from each side of the unit for the periodical maintenance operations: - Directly-coupled electric motors; (For the models URE33 and URE55 single speed 1-phase) (For the models URE110 to URE320 three speeds 1-phase) (For the model URE410 two speeds 3-phase YD) 3. ORIENTATIONS For each size there are 4 available orientations of the heat recovery unit. Depending on the network configuration and available space, the customer can choose among the 4 types indicated below. 2

3 HORIZONTAL ORIENTATION VERTICAL ORIENTATION 3

4 4. NOMINAL TECHNICAL DATA The performances are referred to the following conditions: - exhaust air = 20 C - fresh air = -5 C - nominal air volume Measured at 1 meter from the unit, suction side. 4

5 5. AVAILABLE ACCESSORIES 5.1 CONTROLS C3V Wall-type speed commuter Wall-type control panel, equipped with a 3-position commuter (3 speeds), and on/off switch. The C3V control panel allows for the speed commuting as well as the start/stop of the unit. PCM Wall-type control with commuter, thermostat and season selector Control panel for wall installation, complete with speed commuter, electromechanical thermostat and season selector. Control of the speeds and of the room temperature: - manual commuting of the operating speed; - room temperature control, both in heating and in cooling mode, by means of switching on and off of the electric battery and opening and closing of the control valve, installed upstream the water re-heating coil. 5.2 BY RECUPERATOR BY-PASS DAMPER The recuperator by-pass damper allows the direct free-cooling, in case the external conditions make it a profitable condition. It is constituted by a frame and opposed aluminium blades, equipped with a driving pin for connection with a manual lever or electric actuator. In some cases the recuperator by-pass damper is inserted within the unit itself, thus affecting the dimensions (capacities) of the recuperator itself, and consequent increase of the internal pressure drops (therefore with a decrease of the aeraulic performances of the unit). The technical solution adopted for the URE range (with external duct) avoids the reduction of the dimensions of the recuperator and the decrease of the aeraulic performances of the unit, with the unique requirement to provide for a section of duct external to the unit (room air return duct, picture here below). 5

6 5.2 BC RE-HEATING WATER COIL (included in the unit) The BC heat exchanger is supplied in case you wish to obtain a re-heating, and it is installed directly inside the base unit (to be specified in order phase). Here under follow the thermal performances of such coils in function of the different external conditions. Water temperature C, air temperature 8 C, nominal air volume Tiw Water inlet temperature Tuw Water outlet temperature Qv Air volume Tia Air inlet temperature Tua Air outlet temperature Δpa Air side pressure drop Gw Water flow Δpw Water side pressure drop PT Thermal capacity 6

7 5.4 MBF POST-COOLING WATER COIL (external module) It consists of a thermally-insulated casing with a water heat exchanger to place between the unit and the ductwork in the supply line, meant for the cooling but suitable also for re-heating purposes; the condensate drain discharge, ½" GAS female, is underneath the unit, through a prepainted steel drain pan. PERFORMANCES The performances are referred to the following conditions: Water temperature 7-12 C, air temperature 29 C d.b., relative humidity 50%, nominal air volume. 7

8 Here below follow the thermal performances of such heat exchangers, in function of different external conditions. Performances in heating Tiw Water inlet temperature Tuw Water outlet temperature Qv Air volume Tia Air inlet temperature PT Thermal capacity in heating PF Cooling capacity Δpw Water side pressure drop 5.4 MBF POST-COOLING WATER COIL Tiw Water inlet temperature Tuw Water outlet temperature Qv Air volume Tia Air inlet temperature PT Thermal capacity in heating PF Cooling capacity Δpw Water side pressure drop PERFORMANCES IN COOLING 8

9 5.5 BE RE-HEATING ELECTRIC BATTERY The BE electric battery is supplied when you want to provide for a re-heating and water cannot be used. Such heating elements are inserted inside the heat recovery unit and, having a reduced thickness, allow to reduce to the minimum the resistance at the air passage. The heater requires a single-phase 230/1/50 supply for the sizes 33 and 55, and three-phase 400/3/50 for the sizes from 110 to 410; it is supplied complete with safety thermostats and a control relay. The protection of the supply line has to be provided for by the installer. The capacities are referred to the following conditions: Air temperature 8 C, nominal air volume 5.7 C STP Star-Delta commuter with wall installation case Suitable for speed commuting (triangle = high and star = low) and switching off of the heat recovery unit (models with 3-phase fan). 5.8 ELECTRONIC SPEED CONTROLLER VVM (MOD.33 55) The VVM speed controller is suitable for wall installation and allows to control the fans with single-phase motor. On the display, the following controls are present: - on/off switch - dial for the continuous control of the speed. Technical features 9

10 5.9 SR CONTROL AIR DAMPER It is a calibration device, inserted in the air circuit, to be used when it is necessary to modify the pressure drops of the aeraulic circuit external to the unit, in relation to the supply and exhaust fans available pressure, in order to obtain the air volume correspondent to the desired operating point. It is made of a frame and opposed blades, in aluminium, equipped with a driving pin to connect to a manual lever or electric actuator. The dimensions are indicated in the table below: 5.10 TP PROTECTION ROOF The weatherproof roof, in prepainted metal sheet resistant to corrosion, is compulsory in the URE unit is installed outdoors. It is however recommended, whenever possible, to install the unit in suitable spaces, easily accessible and protected by weather conditions. In order to optimise the transportation, we recommend to order the TP accessory together with the URE unit: it may however be ordered separately in a second moment, too. 10

11 5.11 DP FILTERS PRESSURE SWITCH The DP differential pressure switch, to be requested in order phase, controls the clogging level of the filters, sending a signal (free contact) when reaching the differential pressure set point (between upstream and downstream the filter section); in such situation the differential pressure switch will change the status of the signal free contact, which may be displayed on the control board in order to indicate the need for a periodical cleaning or substitution of the filters. Indeed, in the conditions of the differential pressure switch intervention, the air flow has decreased to such a level so as to significantly reduce the heat recovery performances of the unit. The contact 2-3 closes (and the contact 1-3 opens) as the differential pressure increases WIRING SCHEME: 5.12 AC CIRCULAR JOINTS FOR FLEXIBLE CONNECTIONS The AC circular joints are designed as plenums to install on the supply and exhaust fan mouths, in order to allow for an easy installation with circular flexible connections. The overall dimensions of the AC plenums are indicated in the following table, with reference to the drawing. The diameter (D) of the suction/supply connection is sized so as to limit the pressure drop and maintain the air velocity, inside the circular ducts, within acceptable values. 11

12 5.13 TA ANTI-FREEZE THERMOSTAT The TA anti-freeze thermostat, suitable for installation on board the unit downstream the heat recovery section, is used to protect the plate heat exchanger from freezing, stopping the URE unit (in case of intervention and if correctly wired to the control system). Moreover, if suitably wired for the purpose, it is possible to obtain the closing of the external air dampers (if any) as well as the fans halt. When reaching the preset air temperature value (as measured by the liquid capillary piped), the differential pressure switch will indicate a change in status of the free contact, which may be brought over to the control board in order to turn off the unit and manage whichever function related to the antifreeze protection system. The TA antifreeze safety thermostat intervenes when the capillary pipe detects, for a length of at least 30 cm, a lower temperature than the one previously set with a control dial. As the temperature increases, the contact goes automatically back to its original position. The gas contained within the sensible element increases in volume as the detected temperature rises and, by means of a simple lever, triggers the microswitch. The capillary tube is sensitive to temperature for the whole of its length. The capillary tube must be evenly distributed on the surface to control. It must not show tightening or bends with less than 2 cm angles. In order, we recommend to avoid driving the capillary tube through metal sheets without a suitable protection. The temperature of the unit must never be lower than the setpoint temperature KP - KIT N 4 SUPPORT FEET H=100 MM Support feet in thick galvanised steel, which allow to install the unit in an elevated position with respect to the supporting level. The fixing of the unit is obtained by screws (not supplied). If necessary, in order to limit the transmission of noise and vibrations to the supporting level of the unit, we suggest to install one or more layers of insulating rubber between this and the support feet. As an alternative, anti-vibration dampers could be used (please contact the factory). 12

13 5.15 ON/OFF 3-WAY VALVE VIE ON/OFF + ELECTROTHERMIC ACTUATOR 230V FOR BAP/MBF VALVES These are water side ON/OFF valves, 3-way type, equipped with electro-thermal ON/OFF actuators with 230V supply, used to control the water flow inside BC re-heating coils and MBF post-cooling (or post-heating) ones. The part numbers and the combinations are shown in the following tables; the pressure drop values refer to one single valve, at the nominal water flow, with open valve for heat exchanger passage. COOLING Tw, in 7 C / Tw, out 12 C, air 28 C / 55%, nominal capacities HEATING Tw, in 70 C / Tw, out 60 C, air 20 C, nominal capacities 13

14 5.16 ACTUATOR 22C FC Compact electro-thermal with on/off action IP 44 Shell in self-extinguishing plastic material. Threaded ring in chromed brass M30 x 1.5. Normally closed (NC). Normally open (NA). Stroke: 3,5mm. Supply cable: 1 m Ø 7,2 mm. Opening time: Version 230V 90 sec (start) - 3 Min (end) Absorbed power: 2,5W Ambient temperature: 0 C / +50 C. Compliance to ENEC 03 : EN :2000 and successive integrations. Directive B.T. 2006/95/CE EN ACTUATOR ETE Electro-thermal actuator on/off - IP 20 Auxiliary microswitch normally open (NA) for additional commands (e.g.: pump). Bayonet coupling to the valve body. Device for manual control. Absorbed power: 18W. Stroke: 5,5 mm. Shutter thrust: 250N. Actuation time: 4min. Compliance to Directive B.T. 2006/95/CE EN

15 6. FAN CHARACTERISTICS The following diagrams represent, for each model, the available pressure ( prevalenza utile )at the different air volumes ( portata aria ), after the static heat recovery unit and the filters. URE 33 15

16 URE 55 16

17 URE

18 URE

19 URE

20 URE

21 URE

22 URE

23 7. RECUPERATORS PERFORMANCES 23

24 24

25 8. DIMENSIONS 25

26 26 URE_manual (ENG) rev.00_10/2013