1. Manuals
  2. Brands
  3. Toyotomi Manuals
  4. Air Conditioner
  5. MTN A371DV
  6. Service manual

Toyotomi MTN A371DV Service Manual

Hide thumbs
Table of Contents

Advertisement

Quick Links

Model:
MTN MTG - A371DV

Advertisement

Table of Contents
loading

Related Manuals for Toyotomi MTN A371DV

Summary of Contents for Toyotomi MTN A371DV

  • Page 1 Model: MTN MTG - A371DV...

  • Page 2: Table Of Contents

    CONTENTS 1. Precaution ..............................1   1.1 Safety Precaution ........................1  1.2 Warning ............................1  2. Function ................................ 5   3. Dimension ..............................6   3.1 Indoor Unit ........................... 6  3.2 Outdoor Unit ..........................7  4. Refrigerant Cycle Diagram ......................... 8   5.

  • Page 3: Precaution

    1. Precaution 1.1 Safety Precaution To prevent injury to the user or other people and property damage, the following instructions must be followed. Incorrect operation due to ignoring instruction will cause harm or damage. Before service the unit, be sure to read this service manual at first. 1.2 Warning Installation Do not use a defective or underrated circuit breaker.
  • Page 4 For installation, always contact the dealer or an authorized service center. Do not install the product on a defective installation stand. Be sure the installation area does not deteriorate with age. If the base collapses, the air conditioner could fall with it, causing property damage, product failure, and personal injury.
  • Page 5 Do not open the inlet grill of the product during operation. (Do not touch the electrostatic filter, if the unit is so equipped.) There is risk of physical injury, electric shock, or product failure. When the product is soaked, contact an authorized service center. There is risk of fire or electric shock.
  • Page 6 Operational Do not expose the skin directly to cool air for long time. (Do not sit in the draft). Do not use the product for special purposes, such as preserving foods, works of art etc. It is a consumer air conditioner, not a precision refrigerant system. There is risk of damage or loss of property.

  • Page 7: Function

    2. Function Model Names of Indoor/Outdoor Units Capacity Indoor units Outdoor units Inverter MTN A371DV MTG A371DV Filter killer of formaldehyde Ionizer(O) 8 degree heating(O) Silver Ico Filter(O) Heat compensation(O) Vitamin C Filter(O) Self-diag. function 3M HAM Filter(O) Hydrophilic aluminum fin...

  • Page 8: Dimension

    3. Dimension 3.1 Indoor Unit Model MTN A371DV...

  • Page 9: Outdoor Unit

    3.2 Outdoor Unit More than 30cm More than 60cm (Service space More than 30cm More than 60cm More than 70cm Model MTG A371DV...

  • Page 10: Refrigerant Cycle Diagram

    4. Refrigerant Cycle Diagram INDOOR OUTDOOR CHECK VALVE LIQUID SIDE (Heating Model only) 2-WAY VALVE CAPILIARY TUBE HEAT HEAT EXCHANGE EXCHANGE (EVAPORATOR) (CONDENSER) GAS SIDE REVERSING VALVE 3-WAY VALVE (Heating Model only) ACCUMULATOR COOLING COMPRESSOR HEATING...

  • Page 11: Wiring Diagram

    5. Wiring Diagram 5.1 Indoor Unit MTN-A371DV...
  • Page 12 5.2 Outdoor Unit MTG A371DV O P T I O N A L: H E A TE R H E A T E R 2 CN31 H E A T E R 1 CN33 CN16 CN15 CN14 CN32 CN34 U(R) O U T D O O R YELLOW W(C)

  • Page 13: Installation Details

    6 Installation Details 6.1 Wrench torque sheet for installation Outside diameter Torque Additional tightening torque inch N.cm N.cm Ф6.35 1500(153kgf.cm) 1600(163kgf.cm) Ф9.52 2500(255kgf.cm) 2600(265kgf.cm) Ф12.7 3500(357kgf.cm) 3600(367kgf.cm) Ф16 4500(459kgf.cm) 4700(479kgf.cm) Ф19 6500(663kgf.cm) 6700(683kgf.cm) 6.2 Connecting the cables The power cord of connect should be selected according to the following specifications sheet. Rated current of appliance Nominal cross-sectional area (mm²) >3 and ≤6...

  • Page 14: Pipe Length And The Elevation

    Btu/h Liquid B (m) A (m) (g/m) 5/8’’ 3/8’’ MTN A371DV MTG A371DV (Ф16) (Ф9.53) Caution: The capacity test is based on the standard length and the maximum permissive length is based on the system reliability. The oil trap should be installed per 5-7 meters.

  • Page 15: Installation For The First Time

    6.4 Installation for the first time Air and moisture in the refrigerant system have undesirable effects as below: ● Pressure in the system rises. ● Operating current rises. ● Cooling or heating efficiency drops. ● Moisture in the refrigerant circuit may freeze and block capillary tubing. ●...
  • Page 16 the meter does not indicate -0.1Mpa after pumping 30 minutes, it should be pumped 20 minutes more. If the pressure can’t achieve -0.1Mpa after pumping 50 minutes, please check if there are some leakage points. Fully close the handle Lo valve of the manifold valve and stop the operation of the vacuum pump. Confirm that the gauge needle does not move (approximately 5 minutes after turning off the vacuum pump).
  • Page 17 Close the valve on the charging cylinder and discharge the refrigerant by loosening the flare nut on the 2-way valve approximately 45’ until the gauge indicates 0.3 to 0.5 Mpa. 6). Disconnect the charge set and the charging cylinder, and set the 2-way and 3-way valves to the open position.

  • Page 18: Adding The Refrigerant After Running The System For Many Years

    6).When the electronic scale displays the proper weight (refer to the table), disconnect the charge hose from the 3-way valve’s service port immediately and turn off the air conditioner before disconnecting the hose. 7). Mount the valve stem caps and the service port Use torque wrench to tighten the service port cap to a torque of 18N.m.

  • Page 19: Re-Installation While The Indoor Unit Need To Be Repaired

    6).When the electronic scale displays the proper weight (refer to the gauge and the pressure of the low side), disconnect the charge hose from the 3-way valve’s service port immediately and turn off the air conditioner before disconnecting the hose. 7).
  • Page 20 5). Operate the air conditioner at the cooling cycle and stop it when the gauge indicates 0.1MPa. 6). Set the 3-way valve to the closed position immediately Do this quickly so that the gauge ends up indicating 0.3 to 0.5Mpa. Disconnect the charge set, and tighten the 2-way and 3-way valve’s stem nuts.

  • Page 21: Re-Installation While The Outdoor Unit Need To Be Repaired

    Close the valve on the charging cylinder and discharge the refrigerant by loosening the flare nut on the 2-way valve approximately 45’ until the gauge indicates 0.3 to 0.5 Mpa. 6). Disconnect the charge set and the charging cylinder, and set the 2-way and 3-way valves to the open position Be sure to use a hexagonal wrench to operate the valve stems.
  • Page 22 2. Refrigerant charging Electronic scale Procedure: 1). Connect the charge hose to the charging cylinder, open the 2-way valve and the 3-way valve Connect the charge hose which you disconnected from the vacuum pump to the valve at the bottom of the cylinder.

  • Page 23: Operation Characteristics

    7. Operation Characteristics Temperature Cooling operation Heating operation Drying operation Mode Room temperature ≥17℃ ≤30℃ ＞10℃ 0℃～50℃ -15℃～50℃ Outdoor temperature -15℃～34℃ 0℃～50℃ (For the models with low temperature cooling system) CAUTION: 1. If air conditioner is used beyond the above conditions, the certain protections may action. 2.

  • Page 24: Electronic Function

    8. Electronic function 8.1 Abbreviation T1: Indoor room temperature T2: Coil temperature of evaporator T3: Coil temperature of condenser T4: Outdoor ambient temperature T5: Compressor discharge temperature 8.2 Display function 8.2.1 Icon explanation on indoor display board. ON/OFF indicator This indicator illuminates when the air conditioner is in operation. PRE.-DEF.

  • Page 25: Main Protection

    TEMPERATURE indicator Usually it displays the temperature settings. TIMER indicator This indicator illuminates when TIMER is set ON/OFF. FAN SPEED indicator This indicator illuminates when change the fan speed. Ionizer ( Plasma ) function indicator This indicator illuminates when Ionizer ( Plasma ) function is on. 8.3 Main Protection 8.3.1 Three Minutes Delay at restart for compressor 1 minute delay for the 1...

  • Page 26: Operation Modes And Functions

    8.3.6 Indoor fan delayed open function When the unit starts up, the louver will be active immediately and the indoor fan will open 10s later. If the unit runs in heating mode, the indoor fan will be also controlled by anti-cold wind function. 8.3.7 Compressor preheating functions Preheating permitting condition: If T4(outdoor ambient temperature)＜3...
  • Page 27 The maximum operation frequency of compressor after starting submits to following rule. Fmax=F4 Fmax=F7 Fmax=F8 Fmax=F6 Fmax=F3 If users switch on AC by remote controller, the compressor will run at the Fmax frequency for 7 minutes according to the outdoor ambient temp. During the 7 minutes, the frequency limitation is active. 7 minutes later, the compressor running frequency will be controlled as below: -0.5 -1.0...
  • Page 28 G: Decrease the frequency to the lower level until to F1. H: Run at F1 for 1h.(if T1-Ts<-2 , the compressor will stop) Meanwhile, the compressor running frequency is limited by the current. I3COOL Decrease I2COOL Hold I1COOL Resume Off: Compressor stops. Decrease: Decrease the running frequency to the lower level.
  • Page 29 High Medium 8.4.2.4 Condenser temperature protection ---55 <T3<60 , the compressor frequency will decrease to the lower level until to F1 and then runs at F1.If T3<54 , the compressor will keep running at the current frequency. ---T3<52 , the compressor will not limit the frequency and resume to the former frequency. ---T3>60 for 5 seconds, the compressor will stop until T3<52 .
  • Page 30 Fmax=F2 Fmax=F3 Fmax=F4 Fmax=F5 Fmax=F6 Fmax=F7 Fmax=F8 Fmax=F9 Fmax=F10 If users switch on AC by remote controller, the compressor will run at the Fmax frequency for 7 minutes according to outdoor ambient temp. During the 7 minutes, the frequency limitation is active. 7 minutes later, the compressor running frequency will be controlled as below: +5.0 +4.5...
  • Page 31 While Temp. zone Frequency ΔT=0 as default. Note: When T1-Ts keeps in the same temp. zone for 3 minutes, the compressor will run as the below rules: A~E: Increase the frequency to the higher level until to F10. F: Keep the current frequency. G: Decrease the frequency to the lower level until to F1.
  • Page 32 8.4.3.2 Outdoor fan running rules High 8.4.3.3 Indoor fan running rules Setting Breeze If the compressor stops caused by the room temperature rising, the indoor fan will be forced to run 127 seconds with breeze. During this period, the anti-cold-wind is disabled. If the machine runs in rating capacity test mode, the indoor fan will run with rating speed and the anti-cold-wind function is disabled.
  • Page 33 Auto fan action in heating mode: Medium High 8.4.3.4 Defrosting mode Condition of defrosting: ----T4＞0 , When the units are running, if the following two items are satisfied, the units start defrosting: The units run with T3＜3 for 40 minutes and T3 keeps lower than TCDI for more than 3 minutes. The units run with T3＜3 for 80 minutes and T3 keeps lower than TCDI+2 for more than 3 minutes.
  • Page 34 Defrosting action： For MTN A371DV: Model MTN A371DV...
  • Page 35 8.4.3.5 Evaporator coil temperature protection ----T2> TEH2 , the compressor running frequency decreases to the lower level and runs for 20s. When the frequency decreases to F2 and the T2 is still over TEH2 for 3 minutes, the compressor will stop.
  • Page 36 8.4.5.3 Low indoor room temperature protection In drying mode, if room temperature is lower than 10 , the compressor will stop and not resume until room temperature exceeds 12 . 8.4.5.4 Evaporator anti-freezing protection, condenser high temperature protection and outdoor unit frequency limit are active and the same as that in cooling mode.
  • Page 37 8.4.7.3 Timer off. The machine will turn off automatically when reaching the setting time. 8.4.7.4 Timer on/off. The machine will turn on automatically when reaching the setting “on” time, and then turn off automatically when reaching the setting “off” time. 8.4.7.5 Timer off/on.
  • Page 38 8.4.10 Ionizer function (optional) The indoor unit is equipped with Ionizer, which is controlled by the CLEAN AIR button on the remote controller. When the unit is turned on, press the CLEAN AIR button to activate the function. Press it again to stop the function.

  • Page 39: Troubleshooting

    9. Troubleshooting 9.1 Indoor Unit Error Display Display LED STATUS EEPROM parameter error Indoor unit and outdoor unit communication protection Zero-crossing signal error Indoor fan speed has been out of control Open or short circuit of outdoor temperature sensor or outdoor unit EEPROM parameter error Open or short circuit of room or evaporator coil temperature sensor Outdoor fan speed has been out of control...

  • Page 40: Diagnosis And Solution

    9.2 Diagnosis and Solution 9.2.1 EEPROM parameter error diagnosis and solution Shut off the power supply and turn on it 5s later The problem comes out again Correct the connection Is the EEPROM chip plugged in indoor PCB well? Replace the main PCB of indoor unit...
  • Page 41 9.2.2 Indoor unit and outdoor unit communication protection error diagnosis and solution Turn off the power supply, after 1 minute, connect the power supply, turn on the unit with remote controller The unit does not work normally Check the wiring between indoor and outdoor unit.
  • Page 42 9.2.3 Fan speed has been out of control diagnosis Shut off the power supply and turn on it 5s later The unit does not work normally Turn off the unit, rotate the cross Disassemble the connection between fan. Does it rotate freely? fan and motor, check if the bearing is normal.
  • Page 43 9.2.5 IGBT over-strong current protection diagnosis and solution Check whether the connections between outdoor PCB and IPM are good? Check whether the IPM is fixed to radiator Fastening the IPM to the radiator tightly The unit does not work normally Replace the compressor Replace the IPM 9.2.6 Over voltage or too low voltage protection diagnosis and solution...
  • Page 44 9.2.8 Inverter compressor drive error diagnosis and solution Is the connection of compressor good? Is the wiring sequence right? The voltage Reconnect and retry range proper? Replace the outdoor PCB Replace inverter compressor. 9.2.9 Zero crossing detection error This is alarm signal when the main chip can’t detect over-zero signal. When such failure occurs, the main control board must have fault.

This manual is also suitable for:

Mtg a371dv

Table of Contents