Water cooled vrf, 3 phase, 380-415v, 50hz (225 pages)
Summary of Contents for Midea R290 M thermal Arctic HT Series
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Midea Building Technologies Division Service Manual R290 M thermal Arctic HT Series...
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R290 M thermal Arctic HT Series CONTENTS Part 1 General Information ................3 Part 2 Component Layout and Refrigerant Circuits ........5 Part 3 Control and Field Settings ..............18 Part 4 Diagnosis and Troubleshooting ............63 R290 Service Notice ..................167...
R290 M thermal Arctic HT Series 1 Product Lineup Power 220-240V/1N/50Hz 380-415V/3N/50Hz Supply MHC- MHC- MHC- MHC- MHC- MHC- MHC- MHC- MHC- MHC- Model V4WD2N7 V6WD2N7 V8WD2N7 V10WD2N7 V12WD2N7 V14WD2N7 V16WD2N7 V12WD2RN7 V14WD2RN7 V16WD2RN7 Appearance Note: Please note that these photos are for reference only, actual products may vary.
R290 M thermal Arctic HT Series Part 2 Component Layout and Refrigerant Circuits 1 Layout of Functional Components .............. 6 2 Piping Diagrams ..................14...
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R290 M thermal Arctic HT Series 1 Layout of Functional Components 1.1 4-6kW Pin valve...
R290 M thermal Arctic HT Series 2 Piping Diagrams Refrigerant piping graphic example: High temperature, high pressure gas High temperature, high pressure liquid Low temperature, low pressure gas liquid mixture Low temperature, low pressure gas Note: The refrigerant flow direction shown in the figure is the main refrigerant flow direction for reference only.
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R290 M thermal Arctic HT Series 2.2 Cooling mode 4-6kW 8-16kW...
R290 M thermal Arctic HT Series 2.3 Key components Compressor Tp Discharge temperature sensor Th Return-air temperature sensor High pressure switch H-SEN High pressure sensor 4-way valve L-SEN Low pressure sensor T4 Ambient temperature sensor error Finned tube Heat exchanger...
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R290 M thermal Arctic HT Series ⚫ Electronic expansion valve (EXV): To Control refrigerant flow and reduces refrigerant pressure. ⚫ Liquid reservoir: To hold excess fluid refrigerant when the system is in operation. ⚫ Plate heat exchanger: To transfer heat between two fluids. This has a major advantage over a conventional heat exchanger in that the fluids are exposed to a much larger surface area because the fluids are spread out over the plates.
R290 M thermal Arctic HT Series Part 3 Control and Field settings 1 Stop Operation ..................20 2 Standby Control ..................20 3 Startup Control ..................21 4 Normal Operation Control ............... 24 5 Protection Control ................... 26 6 Special Control ..................31 7 User Interface Field Settings..............
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R290 M thermal Arctic HT Series Notice ▪ The whole system diagram is illustrated as below for the understanding of the locations of key components and sensors. ▪ This is for reference only, it may vary from different scenarios and depend on the actual installation.
R290 M thermal Arctic HT Series 1 Stop Operation The stop operation occurs for one of the following reasons: 1. Abnormal shutdown: in order to protect the compressors, if an abnormal state occurs the system makes a stop with thermo off operation and an error code is displayed on the outdoor unit PCB digital displays and on the user interface.
R290 M thermal Arctic HT Series 3 Startup Control 3.1 Compressor Startup Delay Control In initial startup control and in restart control (except in oil return operation and defrosting operation), compressor startup is delayed such that a minimum of the set re-start delay time 3minutes has elapsed since the compressor stopped, in order to prevent frequent compressor on/off and to equalize the pressure within the refrigerant system.
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R290 M thermal Arctic HT Series 12-16kw compressor startup program when cooling mode ambient temperature is above 12°C & when heating mode ambient temperature is above 0°C 12-16kw compressor startup program when cooling mode ambient temperature is below 12°C & when heating mode ambient temperature...
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R290 M thermal Arctic HT Series 3.3 Startup Control for Heating and Domestic Hot Water Operation Component control during startup in heating and domestic hot water modes Component Wiring diagram label 4-16kW Control functions and states Compressor startup program selected according to...
R290 M thermal Arctic HT Series 4 Normal Operation Control 4.1 Component Control during Normal Operation Component control during heating and domestic hot water operations Component Wiring diagram label Control functions and states 4-16kW Controlled according load requirement from Inverter compressor COMP ●...
R290 M thermal Arctic HT Series 4.5 Electronic Expansion Valve Control The position of the electronic expansion valve (EXV) is controlled in steps from 0 (fully closed) to 480 (fully open). ▪ At power-on: The EXV first closes fully, then moves to the standby position (480 (steps)). After compressor runs the EXV is controlled according to suction superheat discharge temperature, pressure, discharge temperature and compressor speed.
R290 M thermal Arctic HT Series 5 Protection Control 5.1 High Pressure Protection Control This control protects the refrigerant system from abnormally high pressure and protects the compressor from transient spikes in pressure. High pressure protection control Normal operation > 3.5MPa <...
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R290 M thermal Arctic HT Series 5.3 Discharge Temperature Protection Control This control protects the compressor from abnormally high temperatures and transient spikes in temperature. High discharge temperature protection control Normal operation Discharge temperature > 115°C Discharge temperature < 95°C High discharge temperature protection, error code P4 is displayed When the discharge temperature rises above 115°C the system displays P4 protection and the unit stops running.
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R290 M thermal Arctic HT Series 5.5 Voltage Protection Control This control protects the M-Thermal Split from abnormally high or abnormally low voltages. Figure 3-5.6: Compressor voltage protection control Normal operation Voltage ≥ 265V 180V≤Voltage < 256V for 30s or Voltage ≤ 172V Compressor voltage protection, error code H7 is displayed When the phase voltage of AC power supply is at or above 265V, the system displays H7 protection and the unit stops running.
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R290 M thermal Arctic HT Series Anti-freezing control in Cooling mode Cooling mode Min(Twout,Twin,T1)<4 and lasts 5s Compressor stops, water pump keeps running at the maximum output for 5 mins Min(Twout,Twin,T1) 8 Anti-freezing protection in cooling mode Turn to Off Status and running anti-freezing...
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R290 M thermal Arctic HT Series Anti-freezing control in Off status/ Heating mode/ DHW mode Off Status / Heating mode / DHW mode Turn to Off Status 1.T4<3 ,and Min(Twout,Twin,T1)<4 lasts 5s 2.Min(Twout,Twin,T1)<2 Compressor stops, water pump keeps running at the maximum output for 5 mins Min(Twout,Twin,T1)<8...
R290 M thermal Arctic HT Series 6 Special Control 6.1 Oil Return Operation In order to prevent the compressor from running out of oil, the oil return operation is conducted to recover oil that has flowed out of the compressor and into the refrigerant piping. When the oil return operation is being conducted, the outdoor unit refrigerant system main PCB displays code d0.
R290 M thermal Arctic HT Series 7 User Interface Field Settings 7.1 Introduction During installation, the parameters setting should be configured by the installer to suit the installation configuration, climate conditions and end-user preferences. The relevant settings are accessible and programmable through the FOR SERVICEMAN menu on the user interface.
R290 M thermal Arctic HT Series 7.2 Menu Structure For serviceman 7 Other heating source For serviceman 1 DHW setting 7.1 IBH function 1.1 DHW mode 1 DHW setting 7.2 IBH locate 1.2 Disinfect 2 Cooling setting 7.3 dT1_IBH_ON 1.3 DHW priority 3 Heating setting 7.4 t_IBH_DELAY...
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R290 M thermal Arctic HT Series 7.3 FOR SERVICEMAN Menu For serviceman allows installers to input the system configuration and set the system parameters. Press simultaneously for 3 seconds to enter the authorization page. Press to navigate cursor and press to adjust the numerical values.
R290 M thermal Arctic HT Series 7.3.1 DHW heating setting 7.3.1.1 DHW mode DHW mode defines whether hot water demand is needed. Setting Description Enable DHW mode if DHW tank is installed. Disable DHW mode if DHW tank is not installed. In this case, no need to define other settings in DHW setting.
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R290 M thermal Arctic HT Series 7.3.1.3 DHW priority, DHW priority time set, t_DHWHP_RESTRICT, t_DHWHP_MAX DHW priority defines whether domestic hot water or space heating/cooling takes priority. Setting Description When DHW demand and space heating/cooling demand both exist, heat pump will heat the water according to...
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R290 M thermal Arctic HT Series Heating/Cooling turns to DHW turns to PRIORITY PRIORITY t_DHWHP_RESTRICT t_DHWHP_MAX Heating/Cooling TIME SET && DHW mode ON || DHW mode OFF && T5<MIN(T5S, T5STOP)- T5≥MIN(T5S, dT5_ON T5STOP) A min B min && Heating/Cooling mode...
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R290 M thermal Arctic HT Series PUMP_D RUNNING TIME defines the period that DHW pump operates for each timer Diagram below illustrates the effects of PUMP_D RUNNING TIME when Pump_D is installed and PUMP_D TIMER is enable. Status PUMP_D RUNNING TIME Time PUMP_D DISINFECT defines whether DHW pump operation is activated in disinfection mode.
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R290 M thermal Arctic HT Series T4DHWMIN defines the ambient temperature below which the heat pump will not operate in DHW mode. Diagram below illustrates the effects of T4DHWMAX and T4DHWMIN. Heat pump ON with lowest TBH and Heat pump ON...
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R290 M thermal Arctic HT Series Abreviations: T4: Outdoor ambient temperature 7.3.2.4 dT1SC dT1SC defines water temperature hysteresis of activating heat pump. When T1 – T1S ≥ dT1SC and heat pump is within operating ambient temperature range, heat pump provides chilled water to space cooling terminals.
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R290 M thermal Arctic HT Series 7.3.3 Heating setting 7.3.3.1 Heating mode Heating mode defines whether space heating demand is needed. Setting Description Enable heating mode if space heating terminals are installed. Disable heating mode if space heating terminals are not installed. In this case, no need to define other settings in Heating mode.
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R290 M thermal Arctic HT Series 7.3.3.5 dTSH dTSH defines room temperature hysteresis of activating heat pump. dTSH is only applicable if 1 is selected for Room temp. in the Temp. type setting. When TS – Ta ≥ dTSH and heat pump is within operating ambient temperature range, heat pump provides hot water to the...
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R290 M thermal Arctic HT Series T4AUTOHMAX defines the ambient temperature above which the heat pump will not provide hot water for space heating in auto mode. Diagram below illustrates the effects of T4AUTOCMIN, T4AUTOHMAX, T4CMAX and T4HMIN. Abreviations: AHS: Additional heating source IBH: Backup electric heater T4CMAX: The ambient temperature above which heat pump operates with lowest compressor frequency.
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R290 M thermal Arctic HT Series Figure below illustrates the effects of different combinations in Temp. type setting. For single zone control WATER FLOW TEMP. ROOM TEMP. DOUBLE ZONE Zones control Zone 1: Water temperature control Zone 1: Room temperature control For double zone control WATER FLOW TEMP.
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R290 M thermal Arctic HT Series If Room thermostat setting is defined as MODE SET, the interface appears: Mode set priority defines whether cooling mode or heating mode takes priority. Setting Description When heating and cooling switch signal are closed simultaneously, heat pump runs in heating mode.
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R290 M thermal Arctic HT Series Diagram below illustrates the effects of T4_IBH_ON, T4HMIN and T4HMAX. Abreviations: T4: Outdoor ambient temperature IBH: Electric heater T4HMIN: The ambient temperature below which the heat pump will not operate in heating mode. T4HMAX: The ambient temperature above which the heat pump will operate heating mode with lowest compressor frequency.
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R290 M thermal Arctic HT Series 7.3.7.3 EnSWITCHPDC, GAS_COST, ELE_COST EnSWITCHPDC defines whether heat pump and additional heating source switch automatically based on economic performance and system high efficiency. Setting Description Disable EnSWITCHPDC function, T4_AHS_ON need to be defined manually. Additional heating source may work with heat pump depends on the water temperature and heat pump status.
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R290 M thermal Arctic HT Series t_TBH_DELAY defines the delayed start-up time of tank booster heater. Tank booster heater will turn on t_TBH_DELAY minutes later after compressor starts. T4_TBH_ON defines the ambient temperature below which the tank booster heater is on.
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R290 M thermal Arctic HT Series 7.3.8.1 T1S_H.A._H, T5S_H.M_DHW Holiday away setting is used to set the outlet water temperature to prevent water pipes freezing when away from home in cold weather seasons. T1S_H.A._H defines heat pump leaving water temperature for space heating mode during holiday away mode.
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R290 M thermal Arctic HT Series 7.3.11.1 Point check The POINT CHECK menu is used to check the operation of individual components. Use to scroll to the components you want to check and press to toggle the on/off state of the component. If a valve does not turn on/off or a pump/heater does not operate when their on/off state is toggled, please check the connection between component and main PCB and make sure components’...
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R290 M thermal Arctic HT Series 7.3.11.3 Circulated pump running Circulated pump running operation is used to check the operation of the circulation pump. When circulation pump running is turned on, all running components will stop. 60 seconds later, the SV1 will be off, the SV2 will be on.
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R290 M thermal Arctic HT Series The DHW running operation is used to check the operation of the system in DHW mode. During DHW running test running, the default target temperature of the domestic water is 55°C. The TBH(tank boost heater) will turn on after the compressor runs for 10min.
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R290 M thermal Arctic HT Series Abbreviations: T1: Leaving water temperature dT1SH: Water temperature hysteresis of activating heat pump. t_interval_H: The delayed start-up time of compressor in heating mode. 7.3.12.2 Floor drying up For newly-installed under-floor heating systems, floor drying up is necessary to remove moisture from the floor slab and subfloor to prevent warping or rupture of the floor.
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R290 M thermal Arctic HT Series 7.3.13 Auto restart Auto restart sets whether or not the unit re-applies the mode and unit status settings when the power returns following a power failure. If 7.3.6 Room thermostat setting is defined as not 0, Auto restart function will not be applicable.
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R290 M thermal Arctic HT Series 7.3.15 Input definition INPUT DEFINE defines sensors and functions to fulfill with installation. M1 M2 defines the function of M1M2 port Setting Description Remote ON/OFF control of heat pump Remote ON/OFF control of tank booster heater Remote ON/OFF control of auxiliary heating source Smart grid defines whether SMART GRID control signal is connected to hydronic PCB.
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R290 M thermal Arctic HT Series 7.3.17 HMI address setting HMI setting sets the wired controller is master or slave. (0=MASTER, 1=SLAVE) When HMI SET is set to SLAVE, the controller can only switch the operation mode, turn on or off, set the temperature, and cannot set other parameters and functions.
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R290 M thermal Arctic HT Series 7.3.18.4 F-PIPE LENGTH F-PIPE LENGTH select the total length of the liquid pipe. Setting Description Total length of the liquid pipe < 10m Total length of the liquid pipe ≥ 10m 7.3.18.5 PUMP_I_SLIENT OUTPUT PUMP_I_SLIENT OUTPUT can decrease water pump maximum output in order to decrease the noise of heat pump.
R290 M thermal Arctic HT Series 7.3.20 Intelligent function settings 7.3.20.1 Energy correction The actual installation scenario would be different from one to another. The energy metering calculation of the unit could deviate slightly due to the actual installation. Energy correction is to offset the deviation of the energy metering calculation of the unit. Value from -50% to 50%, default is 0.
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R290 M thermal Arctic HT Series Part of operation parameter may be disabled or unavailable and will not appear on the menu.
R290 M thermal Arctic HT Series Over-The-Air 7.5 OTA ( ) guideline HIM software version is above V1.0.0.95 If your wire controller is not connected to the mobile APP, you need to connect to Internet. (Set personal hotspot with smart phone, hotspot name as: SMARTOTA Password: ota12345. And place the smart phone near the wired controller) If your wire controller is already connected to the mobile APP, you can follow the following procedure directly.
R290 M thermal Arctic HT Series 8 USB Function Field Settings USB function helps you to transmit parameters and program easily. When USB disk connect to CN4 port of main control PCB, the USB function interface appears automatically on the wired controller.
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R290 M thermal Arctic HT Series Sub-function 3: Please make sure there is only one applicable hydraulic system program in the USB disk before using this function. Sub-function 4: Please make sure there is only one applicable refrigerant system program in the USB disk before using this function.
R290 M thermal Arctic HT Series Part 4 Diagnosis and Troubleshooting 1 Service Information .................. 64 2 Electric wiring diagram ................72 3 Electric Control Box Layout ............... 76 4 Outdoor Unit PCBs ................... 79 5 Error Code Table ..................89 6 Troubleshooting ..................
R290 M thermal Arctic HT Series 1 Service Information DANGER! ▪ These instructions are exclusively intended for qualified contractors and authorized installers ▪ Work on the refrigerant circuit with flammable refrigerant in safety group A2L may only be carried out by authorized heating contractors.
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R290 M thermal Arctic HT Series substance that may corrode refrigerant-containing components, unless the components are constructed of materials that are inherently resistant to corrosion or are suitably protected from corrosion 1.4 Check of Electrical Devices Repair and maintenance of electrical components should include initial safety checks and component inspection procedures.
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R290 M thermal Arctic HT Series Packaging ⚫ Dispose of the packaging properly. ⚫ Observe all relevant regulations Refrigerant Removal, Evacuation, Charge, Recovery, and Unit Decommissioning WARNING! Due to the feature of the R290 refrigerant, only carry out work when you have specific expert refrigeration knowledge and are competent for handling R290 refrigerant.
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R290 M thermal Arctic HT Series work properly. Hoses should be complete with leak-free disconnection couplings and in good conditions. Before using the recovery equipment, check and verify that it works properly and has been properly maintained, and that any associated electrical components are sealed to prevent ignition in the event of a refrigerant leakage.
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R290 M thermal Arctic HT Series Work shall be undertaken under a controlled procedure so as to minimize the risk of a flammable gas or vapour being present while the work is being performed. All maintenance staff and others working in the local area shall be instructed on the nature of work being carried out. Work in confined spaces shall be avoided.
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R290 M thermal Arctic HT Series prior to any removal of sealed covers, etc. If it is absolutely necessary to have an electrical supply to equipment during servicing, then a permanently operating form of leak detection shall be located at the most critical point to warn of a potentially hazardous situation.
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R290 M thermal Arctic HT Series detail. It is recommended good practice that all refrigerants are recovered safely. Prior to the task being carried out, an oil and refrigerant sample shall be taken in case analysis is required prior to re-use of reclaimed refrigerant. It is essential that electrical power is available before the task is commenced.
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R290 M thermal Arctic HT Series Qualification requirements for maintenance personnel The following information indicates a hazard with a high level of risk which, if not avoided, will result in death or serious injury. These instructions are exclusively intended for qualified contractors and authorized installers Work on the refrigerant circuit with flammable refrigerant in safety group A3 may only be carried out by authorized heating contractors.
R290 M thermal Arctic HT Series 3 Electric Control Box Layout MHC-V4WD2N7 / MHC-V6WD2N7 Inverter Control Box (Inverter PCB’s inside) Power terminal blocks Main Control PCB Main Control Box MHC-V8WD2N7 / MHC-V10WD2N7 Inverter Control Box (Inverter PCB’s inside) Power terminal blocks...
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R290 M thermal Arctic HT Series MHC-V12WD2N7 / MHC-V14WD2N7 / MHC-V16WD2N7 Inverter Control Box (Inverter PCB’s inside) Power terminal blocks Main Control PCB Main Control Box MHC-V12W/WD2RN7 / MHC-V14W/WD2RN7 / MHC-V16W/WD2RN7 Inverter Control Box (Inverter PCB’s inside) Power terminal blocks...
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R290 M thermal Arctic HT Series Note: 1. Main Control PCB consists of Refrigerant system and hydronic system, which is sealed in the hermetic electric control box and placed vertically for safety consideration. 2. The hermetic electric control box of inverter PCB is available to be took out entirely. If there’s something wrong with inverter PCB, it’s suggested to unscrew the cover to identify whether inverter PCB failed (Refer to part 4 Appendix: Guide...
R290 M thermal Arctic HT Series 4 Outdoor Unit PCBs 4.1 Main Control PCB Main Control PCB of 4-16kW...
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R290 M thermal Arctic HT Series Label Port Code Content Rated Voltage CN21 POWER Port for power supply 230VAC S1,S2,S3,S5 Dip switch ,S6,SW9 CN33 EEV1 Port for electrical expansion valve1 0-12V DC H-SEN Port for high pressure sensor 0-5V DC...
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R290 M thermal Arctic HT Series (Port9,10,11,12) - Port for zone 2 pump(P_c)/ zone 1 pump(P_o)/ solar energy pump(P_s)/ pipe pump(P_d) (Port13) - Control port for tank booster heater (Port14) - Control port for internal backup heater 1 (Port15) - Control port for internal backup heater...
R290 M thermal Arctic HT Series 4.2 Inverter PCB 4-6kW Inverter PCB Voltage Port Code Content Label CN32 DC fan power ports Above 156V DC (varying according to frequency) CN12 Port for communication with Main Control PCB 0-5V DC CN25...
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R290 M thermal Arctic HT Series 8-10kW Inverter PCB Voltage Port Code Content Label CN32 DC fan power ports Above 156V DC (varying according to frequency) CN12 Port for communication with Main Control PCB 0-5V DC CN25 H-pro Connect to high pressure switch...
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R290 M thermal Arctic HT Series 12-16kW 1Ph Inverter PCB Voltage Port Code Content Label Power output U of inverter PCB to compressor Above 156V DC (varying according to frequency) Power output V of inverter PCB to compressor Above 156V DC (varying according to frequency)
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R290 M thermal Arctic HT Series 12-16kW 3Ph Inverter PCB Voltage Label Port Code Content Power input L1 of inverter PCB Phase to phase voltage 380VAC Power input L2 of inverter PCB Phase to phase voltage 380VAC Power input L3 of inverter PCB...
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R290 M thermal Arctic HT Series 4.3 IBH PCB 1Ph 3kW IBH PCB Voltage Label Port Code Content CN22 Power input L of IBH PCB Phase to phase voltage 230VAC 3KW-2 Power input N of 3KW IBH Phase to phase voltage 230VAC...
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R290 M thermal Arctic HT Series 3Ph 9kW IBH PCB Voltage Label Port Code Content CN22 L1 L2 L3 Power input L1/L2/L3 of IBH PCB Phase to phase voltage 380VAC 3KW-3 Power input L3 of 3KW IBH Phase to phase voltage 380VAC...
R290 M thermal Arctic HT Series 4.4 Digital Display Output Digital display output in different operating states Outdoor unit state Parameters displayed on Main Control PCB DSP1 On standby Normal operation The current frequency of compressor Error or protection Error or protection code 4.5 DIP Switch Settings...
R290 M thermal Arctic HT Series 5 Error Code Table Water circuit error Error code Description Displayed on water flow failure (10 times of E8) User Interface and Main Control PCB water flow protection User Interface and Main Control PCB...
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R290 M thermal Arctic HT Series Voltage error Error code Description Displayed on Phase loss or phase reversal User Interface and Main Control PCB For 3Ph units Power overvoltage and Power under-voltage protection User Interface and Main Control PCB Protection code...
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R290 M thermal Arctic HT Series Instantaneous overcurrent of PFC software protection Main Control PCB For 3Ph units PFC software continuous 30 s overcurrent protection Main Control PCB For 3Ph units PFC low voltage protection Main Control PCB For 3Ph units PFC power factor is less than 0.8...
R290 M thermal Arctic HT Series 6 Troubleshooting 6.1 Warning WARNING! ▪ All electrical work must be carried by competent and suitably qualified, certified accredited professionals and in accordance with all applicable legislation (all national, local and other laws, standards, codes, rules, regulations and other legislation that apply in a given situation).
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R290 M thermal Arctic HT Series 6.2 E0, E8 Troubleshooting Digital display output Description Error code Description water flow failure water flow protection 5 times of No-water detection failures in a row before pump on No-water detection failures before pump...
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R290 M thermal Arctic HT Series Layout of main component E0(**%) /E8(**%) is displayed on the User Interface. The percentage indicates possible cause of water flow failure, which is illustrated as note 1. User Interface Correct Dip switch Procedure E0 / E8: Water flow failure...
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R290 M thermal Arctic HT Series Check the water pump indicator lights, and it shows water pump is normal (Willo water pump green light indicates Check the details of Note 2 normal ; Xinjie water pump 5 lights all on indicates normal) 1.
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R290 M thermal Arctic HT Series Note 1 : The meaning of percentage of water pump output(displayed on the user interface) Percentage Water pump model Brand Description Para 25/9 IPWM-130-1 WILO IPWM connection port short circuited APM25-9-130/180 SHIMGE PWM feedback signal loss...
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R290 M thermal Arctic HT Series Note 3: The possible error and solutions of water pump water pump failure The possible causes of and solutions Description Possible cause Solution Water pump leak Replace the sealing ring Water inlet and outlet pipe connected reversely.
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R290 M thermal Arctic HT Series 6.3 E2 Troubleshooting Digital display output Description Error code Description Communication fault between User Interface and Main Control PCB Main Control PCB side: Communication failure with User Interface lasts 2 mins Triggering User Interface side: No communication reply from Main Control PCB for 1 min...
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R290 M thermal Arctic HT Series Procedure E2: Communication fault between User Interface and the unit Communication cables from port X/HA, Reconnect the communication cables Y/HB was disconnected, or misconnected correctly Communication cables from port X/HA, Replace the communication cables...
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R290 M thermal Arctic HT Series 6.4 H0 Troubleshooting Digital display output Description Error code Description Communication error of Main Control PCB Triggering Communication failure lasts 1 min Procedure H0: Communication error of Main Control PCB Replace the Main Control PCB...
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R290 M thermal Arctic HT Series 6.5 H1 Troubleshooting Digital display output Description Error code Description Communication error between Main Control PCB and inverter PCB Triggering Communication failure occurs after powering on the unit for 2 mins CN43 COMM (Main Control PCB) LED2 &...
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R290 M thermal Arctic HT Series Procedure For 1Ph models H1:Communication error between Main Control PCB and Inverter PCB Check whether power supply for ODU is abnormal.( The normal Adjust power supply range is 190-264V Check whether the LED2 on...
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R290 M thermal Arctic HT Series For 3Ph units H1:Communication error between Main Control PCB and Inverter PCB 1. 1. Check whether power supply for ODU is abnormal.( The normal 1.Adjust power supply range is around 342-456V) 2.Connect L1,L2,L3 correctly and firmly 2.
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R290 M thermal Arctic HT Series 6.6 Hd Troubleshooting Digital display output Description Error code Description Communication fault between master unit and slave unit. For cascade system, the communication failure between master Triggering unit and slave unit lasts 2mins and above...
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R290 M thermal Arctic HT Series Procedure Hd:The communication fault between master unit and slave unit. Check “Unit Status-Operation parameter- Online unit number” on the User Interface, and the number is consistent with the actual unit number Communication cables between port...
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R290 M thermal Arctic HT Series 6.7 E5, E6, E9, EA, FC1, H2, H3 Troubleshooting Digital display output Description Code Description Port Location T3 Outdoor unit heat exchanger CN34 bottom temperature sensor error T4 Ambient temperature sensor error CN45 Th Return-air temperature sensor...
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R290 M thermal Arctic HT Series Procedure E5, E6, E9, EA, FC1, H2, H3: Temperature sensor error Temperature sensor connection on Main Reconnect the temperature sensor Control PCB is loose, misconnected, correctly and keep it dry broken or moisturized Pull out temperature sensor, measure sensor resistance: If the resistance is too low(<...
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R290 M thermal Arctic HT Series 6.8 E3, E4, E7, Eb, EC, Ed, HA, H9 Troubleshooting Digital display output Description Code Description Port Location (Main Control PCB) T1 Electric Heater/AHS water outlet CN39 temperature sensor error T5 Water tank temperature sensor...
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R290 M thermal Arctic HT Series Note 1: Dip switch settings or User Interface settings Code Description Main Control PCB can not detect the right sensor value. IBH function is on(Dip switch S1-3/4 is set IBH available, and User Interface- For Serviceman - Other heat source –...
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R290 M thermal Arctic HT Series Procedure E3, E4, E7, Eb, EC, H9: Temperature sensor error Check the Dip switch settings or User Reset dip switch, and reboot the unit, make sure parameter are set available Interface settings as illustrated above...
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R290 M thermal Arctic HT Series 6.9 H5 Troubleshooting Digital display output Description Code Description Location Ta room temperature sensor error Inserted on PCB of User Interface Procedure H5:Ta Temperature sensor error Replace User Interface...
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R290 M thermal Arctic HT Series 6.10 H8, P21, P27 Troubleshooting Digital display output Description Code Description Port Location(Main Control PCB) H-SEN High pressure sensor error L-SEN Low pressure sensor error CN46 H-SEN and L-SEN connected reversely CN3/ (Detect when compressor is off)
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R290 M thermal Arctic HT Series Procedure H8, P21: Pressure sensor error Loose, misconnected, broken or wet Reconnect the temperature sensor temperature sensor connection on Main securely and ensure it remains dry Control PCB. Measure the resistance value of sensor, and it’s consistent with the curve(Refer to...
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R290 M thermal Arctic HT Series 6.11 E1 Troubleshooting Digital display output Description Error code E1 (For 3Ph units) Description Phase loss or phase reversal Triggering At least one of L1/L2/L3/N misconnected or disconnected Relative Terminal ports and blocks locations...
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R290 M thermal Arctic HT Series 6.12 H7 Troubleshooting Digital display output Description Error code Description Power overvoltage
and Power under-voltage protection Input voltage<170V or Input voltage≥265V Triggering (The unit operating normally if 250V≥input voltage≥180V) Procedure H7: Power overvoltage
and Power under-...
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R290 M thermal Arctic HT Series 6.13 P0 Troubleshooting Digital display output Description Error code Description Low pressure protection 1. Main Control PCB detected that the low pressure <0.12MPa lasting more than 30 mins 2. Main Control PCB detected that low pressure <0.13MPa & compressor shutting off Triggering more than 2 mins at the same time.
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R290 M thermal Arctic HT Series Procedure P0: Low-pressure protection Check “Unit Status-Operation parameter- P1 comp. pressure & P2 comp. pressure” Replace low-pressure sensor on the User Interface and P1=P2 while the unit is off T4 sensor fell out from the fixed position...
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R290 M thermal Arctic HT Series Reboot the unit, hold the electronic Check for blockages between the expansion valve coil to feel whether it is electronic expansion valve and Copper working, and listen for a “Click” sound filter. Clean the unit again, and recharge...
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R290 M thermal Arctic HT Series 6.14 P1 Troubleshooting Digital display output Description Error code Description High pressure switch protection The Main Control PCB detected that the high pressure was ≥ 3.5 Mpa Triggering High pressure switch The location of high pressure switch refer to Part 2 Component Layout and Refrigerant...
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R290 M thermal Arctic HT Series Procedure P1 occurs in Cooling mode High-pressure switch plug from the inverter control box is loose or Reconnect high-pressure switch securely misconnected Use a digital multimeter to measure high- pressure switch with buzzer. Power off and power on again , P1 error If buzzer doesn’t sound, replace high-...
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R290 M thermal Arctic HT Series Request aftersales service P1 occurs in Heating/DHW mode Check and clean pipe and filter, Ensure Check “Unit Status-Error info.” on water pressure and water-flow rate is in the User Interface, and E8/E0/P5 code Proper range as above.
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R290 M thermal Arctic HT Series Replace the inverter control box The proper water pressure range:(0.3bar-3bar) The proper water flow rate range P1 occurs in Off status Check “Unit Status-Operation parameter- P1 comp. pressure & P2 comp. pressure” Request aftersales service on the User Interface, and P1&P2<3.5MPa...
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R290 M thermal Arctic HT Series 6.15 P3 Troubleshooting Digital display output Description Error code Description Overcurrent protection Triggering The Main Control PCB detected that the input current is higher than protection value Terminal block Nameplate Refer to Nameplate for rated refrigerant charge volume.
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R290 M thermal Arctic HT Series Check and clean pipe and filter, make Check “Unit Status-Error info.” on the User sure water pressure and water flow rate Interface, and E8/E0 code also occurred is in the proper range barely at the same time For more details, refer to E8/E0 troubleshooting procedure.
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R290 M thermal Arctic HT Series P3 occurs in cooling mode Measure the input voltage of terminal block, Adjust the power supply based on the and it’s<198V rated voltage range Use a current clamp to measure the current between two power cables connected to “L”...
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R290 M thermal Arctic HT Series misconnected Use a digital multimeter to measure the resistance between each two of compressor terminals. If the resistance <10 Ohm or the Replace the compressor resistance=0 (Short circuited), compressor failed Power off the unit, and identify possible inverter PCB failure.
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R290 M thermal Arctic HT Series 6.16 P4 Troubleshooting Digital display output Description Error code Description Compressor protection against excessively-high discharge temperature The Main Control PCB detected that the compressor discharge temperature was ≥ Triggering 115℃ Tp discharge temp. sensor...
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R290 M thermal Arctic HT Series Procedure Pull out Tp temperature sensor from compressure fixed sleeve, leave it in the air for 10 mins, if the temperature difference between sensor and air is greater than 5℃, the sensor failed. Replace Tp temperature sensor You can also measure the resistance and compare it with sensor’s resistance...
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R290 M thermal Arctic HT Series 6.17 Pd Troubleshooting Digital display output Description Error code Description Protection for excessively-high condensing temperature in cooling mode Main Control PCB detected that the condensing temperature was ≥65℃ in cooling Triggering mode Relative ports and locations Nameplate Refer to Nameplate for rated refrigerant charge volume.
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R290 M thermal Arctic HT Series Procedure Pd: Protection for excessively-high condensing temperature in cooling mode Check “Unit Status-Operation parameter- Replace Main Control PCB or high- P1 comp. pressure & P2 comp. pressure” pressure sensor.(Refer to H8/P21 on the User Interface and P1=P2 while...
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R290 M thermal Arctic HT Series 6.18 HP Troubleshooting Digital display output Description Error code Description Low pressure protection in cooling mode Main Control PCB detected that the suction pressure P2<0.35Mpa for 5 seconds in Triggering cooling mode and compressor running over 300 seconds.
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R290 M thermal Arctic HT Series Procedure HP: Low-pressure protection in cooling mode Install the Tw_out sensor back to the Check whether Tw_out sensor felt out installation port so actual temperature from installation port can be detected. Pull out Tw_out/Tw_in sensor from plate...
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R290 M thermal Arctic HT Series 6.19 bA Troubleshooting Digital display output Description Error code Description T4 sensor out of operation range protection In heating/ DHW mode, the error occurs when T4≥65℃ or T4<-25℃ Triggering In cooling mode, the error occurs when T4≥65℃ or T4<-5℃...
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R290 M thermal Arctic HT Series Procedure bA: T4 sensor out of operation range protection The actual ambient temperature ≥65℃ The actual ambient temperature is out of or <-25℃ in heating mode; or the actual range, so Protection program activated.
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R290 M thermal Arctic HT Series 6.20 PP, Hb Troubleshooting Digital display output Description Error code Protection for abnormal temperature Description difference between outlet water and inlet PP occurs 3 times in heating/DHW mode water Twout-Twin≥3℃ and lasts 15 mins in PP occurs 3 times in heating/DHW mode;...
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R290 M thermal Arctic HT Series Procedure PP in cooling mode Outlet pipe and inlet pipe connected Re-connect the pipes securely reversely Tw_in sensor and Tw_out sensor connected reversely on plate heat Re-connect the sensors securely exchanger or on Main control PCB...
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R290 M thermal Arctic HT Series PP/Hb in heating/DHW mode Outlet pipe and inlet pipe connected Re-connect the pipes securely reversely Tw_in sensor and Tw_out sensor connected reversely on plate heat Re-connect the sensors securely exchanger or on Main control PCB...
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R290 M thermal Arctic HT Series 6.21 P5 Troubleshooting Digital display output Description Error code Description The big temperature difference between outlet water temp. and inlet water temp. Twout-Twin≥30℃ in heating/DHW mode Triggering Twout-Twin≥17℃ in cooling mode Tw_in Tw_out Procedure P5:The big temperature difference between...
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R290 M thermal Arctic HT Series compare with sensor’s resistance characteristics table (Refer to part 4 Appendix), If the resistance is not consistent, the sensor has failed. Whether the heating water temperature rises rapidly, the cooling water temperature drops rapidly and the unit stops quickly.
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R290 M thermal Arctic HT Series 6.22 F75 Troubleshooting Digital display output Description Error code Description Protection for insufficient discharge overheating degree. Triggering Tp-Tc < 0℃ and last 10 mins Tp discharge temp. sensor Nameplate Refer to Nameplate for rated refrigerant charge volume.
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R290 M thermal Arctic HT Series Re-wrap the discharge temperature sensor Tp temperature sensor is NOT well insulated. with insulation material Pull out Tp temperature sensor from compressor fixed sleeve, leave it in the Replace discharge temperature sensor and it...
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R290 M thermal Arctic HT Series 6.23 F1 Troubleshooting Digital display output Description Error code Description Protection for DC bus undervoltage Triggering For single phase inverter PCB, the DC bus voltage≤200VDC BUS voltage(P-N) (Inverter PCB)
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R290 M thermal Arctic HT Series Procedure For single phase: F1: Protection for DC bus undervoltage Power off the unit, and identify whether inverter PCB failed. (Refer to part 4 Replace the inverter control box Appendix: Guide for identifying inverter PCB failure) Power on the unit, when it’s standby,...
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R290 M thermal Arctic HT Series 6.24 C7 Troubleshooting Description Error code Description Over-high temperature protection for IPM module IPM module temperature ≥ 95℃ Triggering Digital display output Procedure C7:Over-high temperature protection for IPM module The unit was installed in a site that is...
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R290 M thermal Arctic HT Series 6.25 H4, L** Troubleshooting Digital display output Description Error code Description Note 3 times of “L1*” in 60 mins Check the specific code on digital display panel on the Inverter module protection Main Control PCB...
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R290 M thermal Arctic HT Series Bus voltage excessively high error Phase loss error of three-phase power supply For 3Ph units Abnormal phase current sampling bias Fan motor code mismatch error IPM protection (FO) Module type mismatch Motor failed to start...
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R290 M thermal Arctic HT Series Procedure H4, L**: Inverter module protection Power off the unit, the compressor connection cables was disconnected, or Reconnect the cables correctly misconnected Use a digital multimeter to measure the resistance between each two of Replace the compressor compressor terminals.
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R290 M thermal Arctic HT Series 6.26 H6, HH, J** Troubleshooting Digital display output Description Error code Description Note Fan failure 10 times of H6 in 120mins Check the specific code on digital display panel on the Fan module failure...
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R290 M thermal Arctic HT Series Procedure H6, HH: Fan failure Power off the unit, the fan connection cables was disconnected, or Reconnect the cables correctly misconnected Use a digital multimeter to measure the resistance between each two of fan Replace the fan terminals.
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R290 M thermal Arctic HT Series 6.27 HF Troubleshooting Digital display output Description Error code Description Outdoor unit EEPROM error The driving program of inverter PCB is detected as being mismatched with Dip Triggering switch Relative ports Dip switch S5 S6...
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R290 M thermal Arctic HT Series 6.28 Pb Troubleshooting Digital display output Description Error code Description Pb is the indicator that shows the system is running in anti-freezing control Triggering Refer to Part 3 - Protection control – Anti-freezing protection control...
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R290 M thermal Arctic HT Series 6.29 C2 Troubleshooting Digital display output Description Error code Description Relay adhesion on IBH PCB Relay: Poor contact, relay deformation, relay aging, etc. Triggering External factors : overcurrent, over high ambient temperature, etc. Relays and...
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R290 M thermal Arctic HT Series 6.30 C3, C4 Troubleshooting Digital display output Description Error code Current transformer failure or circuit Description C3≥3 times failure of IBH PCB Incorrect Dip switch S1, cables with IBH connected improperly; Triggering Overvoltage, IBH failure etc.
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R290 M thermal Arctic HT Series Procedure C3,C4 Confirm the Dip Switch S1 on main Correct Dip switch S1 control PCB, and it’s correct. The cables between IBH PCB(CN52) and Main Control PCB(CN9), the cables of Reconnect the cables correctly...
R290 M thermal Arctic HT Series 7 Discharge / Suction pressure and temperature range The following parameter ranges are used to roughly determine whether the system is running properly: Discharge temperature(Tp) on heating/DHW mode T4<-10℃ Twout+10<Tp<Twout+30 -10℃≤T4<10℃ Twout+10<Tp<Twout+30 Twout+10<Tp<Twout+25 10℃≤T4<25℃...
R290 M thermal Arctic HT Series 8 Appendix to Part 4 8.1 Temperature Sensor Resistance Characteristics Applied to T3 Outdoor unit heat exchanger bottom temperature sensor T4 Ambient temperature sensor Th Return-air temperature sensor T2 Plate heat exchanger outlet refrigerant temperature sensor...
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R290 M thermal Arctic HT Series Applied to TW_in Plate heat exchanger inlet water temperature sensor TW_out Plate heat exchanger outlet water temperature sensor T5 Water tank temperature sensor TW2 Zone 2 water flow temperature sensor R50=17.6KΩ±3%,B0/100=3970K±2% Temp. (°C) Resistance (kΩ) Temp.
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R290 M thermal Arctic HT Series 8.2 Pressure and Output voltage characteristics of Pressure sensor Pressure and Output voltage characteristics of Pressure sensor 5.00 Low pressure sensor High pressure sensor 4.50 y = 2x + 0.5 y = 0.87x + 0.5 4.00...
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R290 M thermal Arctic HT Series 8.3 Guide for identifying inverter PCB failure Before measuring the inverter PCB, please confirm steps below in advance : 1) Cut off the power supply ; 2) Wait for 10 mins for capacitor discharging in order to avoid the electric shock 3) Remove all connections wires 4) To identify whether inverter PCB of 1Ph models failed, follow the guide to test inverter circuit.
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R290 M thermal Arctic HT Series Inverter circuit (Fan module/ Compressor module): Test point Order Normal Abnormal +(Red) -(Black) 0.3-0.7V 0 /infinite Note: 1. If any one of test value abnormal, the inverter PCB failed. Request aftersales service and replace the inverter control box.
August 2023 | SN 001 Midea will introduce a new generation of heat pumps that operate using R290 refrigerant. Theoretically, R290 is a highly flammable A3 refrigerant, but its risk can be effectively eliminated through product design and various aspects of control.
Transportation precautions Warehouse management requirements Transportation regulations: ADR, IMDG, IATA Only desk telephones will be set up for ADR regulations: Equipment containing less than 12 kg of communication within the warehouse. No mobile flammable refrigerant is not subject to transportation regulations if phones are allowed.
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sides of the unit and the wall should be more than 65 cm, the bottom of the unit must be more than 1.8 m above the ground, Tools required and an installation height of more than 15 cm should be When performing pipeline welding or maintained on the top of the heat pump.
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Postal code: 528311 mbt.midea.com / global.midea.com Midea reserves the right to change the specifications of the product, and to withdraw or replace products without prior notification or public announcement. Midea is constantly developing and improving its products. Please note that all the pictures in the document are for reference only. Actual products may vary.
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