CLASS UNIT Table of content Safety precautions Product Overview Wiring Overview Functions Commissioning Preventive maintenance Troubleshooting Parameters/Commissioning Sheet CE Declaration Operation and maintenance instructions – CLASS UNIT TAC5...
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Air from outdoor to the AHU (OA) Air from the AHU to the building (SA) Air from the building to the AHU (ETA) Air from the AHU to outdoor (EHA) PLATE HEAT HEATING COIL EXCHANGER (ELECTRICAL) Operation and maintenance instructions – CLASS UNIT TAC5...
Unit should always be operated with closed doors and panels. • If the unit is installed in a cold place make sure that all joints are covered with insulation and are well taped. Operation and maintenance instructions – CLASS UNIT TAC5...
7. GF-ePM10 50% filter on exhaust air 3. Exhaust fan 8. Access panels 4. Air/Air heat exchanger ( + modulating 100% by-pass) 9. Air inlet damper 10. Internal postheating electric coil (KWout) Operation and maintenance instructions – CLASS UNIT TAC5...
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AIR VOLUME AND DIMENSIONS SIZE AIR VOLUME CLASS UNIT 1000 1050 m³/h 291 l/s Operation and maintenance instructions – CLASS UNIT TAC5...
O.R.3 (output relay 3 - SAT3) = HEATING DEMAND OUTPUT T5 = supply T° sensor for KWout coil (prewired) O.R.4 (output relay 4 - SAT3) = BYPASS STATUS KWout = output for KWout capacity control (prewired) Operation and maintenance instructions – CLASS UNIT TAC5...
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SAT3 must be plugged onto the control board circuit (see fig.1). Attention: The SAT3 must be plugged in before the circuit is powered. SAT must be plugged in correctly, wrong positioning can damage both circuits permanently. Operation and maintenance instructions – CLASS UNIT TAC5...
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3.2 INTERNAL WIRING DIAGRAM CLASS UNIT Operation and maintenance instructions – CLASS UNIT TAC5...
A CO 2 sensor option is available for selection when ordering. Once this option is selected, the sensors are prewired and pre-configured to be ready for use. • 4 - MODE OFF : This stops the AHU Operation and maintenance instructions – CLASS UNIT TAC5...
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4.2 TEMPERATURE CONTROL There are several options available on CLASS UNIT units to ensure a comfortable temperature. The options are controlled either via supply or extract air temperature. Supply Air Temperature Supply temperature control is the default setting. This involves keeping a constant supply air temperature without consideration to the load in the premises.
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The neutral band is added to the comfort setpoint for the activation of the cooling function. The neutral bands has to be configured in the advanced setup. Operation and maintenance instructions – CLASS UNIT TAC5...
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• Constant pressure on supply and exhaust: one pressure setpoint (percentage of the nominal setpoint) for supply and one for exhaust. Operation and maintenance instructions – CLASS UNIT TAC5...
Position switch (COM4) - CID010007 The most basic interface to control a CLASS UNIT air handling unit is the 4 position swich. This swith will allow to control the unit to its three configured airflow (low, medium and high) and as a fourth position, the unit is switched off.
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Main menu. See Section 6.1.2. The main menu is presented as a rotary menu. After pressing the “menu”-button at the bottom left corner of the Home Screen, the rotary menu will be shown. Operation and maintenance instructions – CLASS UNIT TAC5...
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The appearence of the im- age varies depending on the type of air handling unit and its selected functions and/or options. Flow chart symbols: Bypass (closed/open) Electrical heating coil Motorised damper (open/closed/opening) Operation and maintenance instructions – CLASS UNIT TAC5...
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The seasonal management menu allows for the deacti- vation of heating coils, cooling coils and bypass freecool- ing function based upon a year calendar. In between the programmed interval, the selected function is OFF. Operation and maintenance instructions – CLASS UNIT TAC5...
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Configuration of service related settings. A maintenance warning interval can be configured as wel as the filter clogging alarm. Advanced setup A code and a special training are desired for access to this menu. Operation and maintenance instructions – CLASS UNIT TAC5...
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(Pa), input signal strenght (%) or torque (%). For both “Airflow TEMPERATURE control” and “Torque control”, three setpoints are available: Low, FIRE ALARM medium and high. Setting Settings Factory range setting Operating mode Airflow Airflow Demand control Pressure Torque Operation and maintenance instructions – CLASS UNIT TAC5...
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Setting Range Factory set- ting Control Supply Supply Exhaust Supply+Exhaust Ratio exhaust /supply 5...999% 100% Sleep factor on K3 10...100% 100% Pressure initialisation Via Airflow Airflow Via Pressure Start reference initia- lisation Operation and maintenance instructions – CLASS UNIT TAC5...
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When the commissioning has been successfull and this is confirmed in this AIRFLOW REGULATION menu, the commissionig menu will not be activated automatically anymore. TEMPERATURE Setting Settings Factory FIRE ALARM range setting PERIODIC MAINTENANCE Confirmation of COMMISSIONING COMPLETED successfull commis- sioning Operation and maintenance instructions – CLASS UNIT TAC5...
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The system can be defined as a negative or a positive logic. A negative START TORQUE logic airflow drops when analogue signal on K2 is > than the setpoint. Setting Settings Factory range setting Reaction speed 0...10 Logic Positive Negative Negative Operation and maintenance instructions – CLASS UNIT TAC5...
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Setting Settings Factory range setting Supply or Extract tempe- Supply Supply rature control? Extract Reaction speed 1...10 Supply air, min 0...20°C 15,0°C Supply air, max 16...50°C 28,0°C Stop fan if T°Supply <5°C Operation and maintenance instructions – CLASS UNIT TAC5...
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This function is activated auto- BOOST matically when an electrical heating coil is activated. POST VENTILATION Setting Settings Factory INTERNAL COILS range setting EXTERNAL COILS Activation Time 0...9999sec 90sec Operation and maintenance instructions – CLASS UNIT TAC5...
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HMI. The configurable temperatures are exhaust temperatures. Frost protection cycle active Frost protection alarm Setting Settings Factory range setting T° Low 1...3°C +1,0°C T° High 1...5°C +5,0°C Stop supply airflow Operation and maintenance instructions – CLASS UNIT TAC5...
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“OFF”-mode. Setting Settings Factory range setting Reset timer Fan run time activation Display time Service alarm time 0...999999h Stop fan 0...999999h Operation and maintenance instructions – CLASS UNIT TAC5...
• Vacuum clean any accumulations of dust in the unit. • Inspect and gently vacuum clean the heat exchanger if necessary. Use a brush to protect the fins. • Clean any condensation stains • Clean any accumulations in the drain pan. Operation and maintenance instructions – CLASS UNIT TAC5...
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Clean the fan space, if needed. Remove the fans if necessary. 2. Check seals on the unit: Ensure that the side access panels are fully closed and that the seals are intact. Replace if necessary. Operation and maintenance instructions – CLASS UNIT TAC5...
B.11 Fan 1 failure B.12 Fan 2 failure B.13 Fan 3 failure B.14 Fan 4 failure TAC control board AL1 relay O.R.1 LED ALARM LED AF Fans Alarm stopped Auto reset: yes Operation and maintenance instructions – CLASS UNIT TAC5...
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S.40 Pressure alarm from Pressure Switch* TAC control board AL1 relay O.R.1 LED ALARM LED AF Fans Closed Run* Auto reset: yes * unless the status has been changed in advanced setup Operation and maintenance instructions – CLASS UNIT TAC5...
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Initialisation of the reference pressure - Extract air flow too high - Min. limit of the motor TAC control board AL1 relay O.R.1 LED ALARM LED AF Fans ALARM Stopped Auto reset: no Operation and maintenance instructions – CLASS UNIT TAC5...
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LED AF Fans Alarm status Stopped Auto reset: no - Solutions: • Try a TOTAL RESET of the data using the advanced setup. If still not resolved, order a new circuit board. Operation and maintenance instructions – CLASS UNIT TAC5...
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* The fans are stopped by default in the event of a fire alarm but, via the advanced setup, it is possible to configure a fixed airflow for supply (contact IN7 needs to be closed) and for exhaust (contact IN8 needs to be closed). Operation and maintenance instructions – CLASS UNIT TAC5...
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• Communications failure between the TAC circuit and the HMI - Effects: Displayed on HMI TACtouch Text displayed LED ALARM LED Pa CB COM ERROR TAC control board AL1 relay O.R.1 LED ALARM LED AF Fans Alarm status Auto reset: yes Operation and maintenance instructions – CLASS UNIT TAC5...
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Sensor T4 disconnected T.41 Sensor T4 short circuit TAC control board AL1 relay O.R.1 LED ALARM LED AF Fans Alarm status Manual reset mandatory. * unless the status has been changed in advanced setup Operation and maintenance instructions – CLASS UNIT TAC5...
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7.11 TYPE 10 BIS: DRAIN PUMP ALARM - Conditions: • Only for CLASS UNIT LP - Causes: • The level of condensate is higher than a set Setting (approx. 1.5 cm). It can also be activated if the pump is not present or defective...
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- Effects: Displayed on HMI TACtouch Text displayed LED ALARM LED Pa A.10 Anti-freeze - Reduced air flows TAC control board AL1 relay O.R.1 LED ALARM LED AF Fans Auto reset: yes Operation and maintenance instructions – CLASS UNIT TAC5...
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Text displayed LED ALARM LED Pa S.60 Post-cooling - T° of the supply air too high TAC control board AL1 relay O.R.1 relay of SAT3 LED ALARM LED AF Fans Auto reset: yes Operation and maintenance instructions – CLASS UNIT TAC5...
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Anti-freeze protection of the waterborne post-cooler (EBA-) A.43 Anti-freeze protection of the waterborne reversible coil (EBA+-) TAC control board AL1 relay O.R.1 LED ALARM LED AF Fans Alarm Status Stopped Manual reset mandatory. Operation and maintenance instructions – CLASS UNIT TAC5...
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• Alarm indicating that the hours limit for the maintenance of the filters has been reached - Effects: Displayed on HMI TACtouch Text displayed LED ALARM LED Pa FILTERS ALARM TAC control board AL1 relay O.R.1 LED ALARM LED AF Fans Auto reset: via dedicated reset Operation and maintenance instructions – CLASS UNIT TAC5...
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This must be done by an accredited technician. A code and special training is mandatory to access this menu group. The table below is valid for controllers generation TAC. RANGE SIZE TAC DG CLASS UNIT 884229 Unique Operation and maintenance instructions – CLASS UNIT TAC5...
% on K3 = Assignment Pa = O [V] O [Pa] Constant pressure: % on K3 = Ratio exhaust / supply: If KWin option: T° KWin = °C KWout T° KWout = °C Operation and maintenance instructions – CLASS UNIT TAC5...
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Enter details when the Setting of a parameter has been changed (use only one row per parameter): Setting before Setting of Date of Setting of Date of Parameter Name change change #1 change #1 change #2 change #2 Operation and maintenance instructions – CLASS UNIT TAC5...
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Authorized to compile the technical file: Name: Nicolas Pary Address: Parc-industriel de Sauvenière 102 Chaussée de Tirlemont B5030 Gembloux Signature: Place and date: Gembloux 2021-05-17 Signature: Name: Jean-Yves Renard Position: R&D Director Operation and maintenance instructions – CLASS UNIT TAC5...
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Operation and maintenance instructions – CLASS UNIT TAC5...
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Version: 20220414 We reserve the right for changes.
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