Toyotomi MTN-MTG 256DV User manual

Service Manual
MODEL:
MTN-MTG 256DV

CONTENTS
1. Precaution ................................................................................................................................................. 1
1.1 Safety Precaution ................................................................................................................................................ 1
1.2 Warning ............................................................................................................................................................... 1
2. Function .................................................................................................................................................... 4
3. Dimension ................................................................................................................................................. 6
3.1 Indoor Unit........................................................................................................................................................... 6
3.2 Outdoor Unit ........................................................................................................................................................ 7
4. Specification ............................................................................................................................................. 8
5. Refrigerant cycle diagram ....................................................................................................................... 9
6. Wiring diagram ....................................................................................................................................... 10
6.1 Indoor Unit......................................................................................................................................................... 10
6.2 Outdoor Unit ...................................................................................................................................................... 10
7. Installation details .................................................................................................................................. 11
7.1 Wrench torque sheet for installation .................................................................................................................. 12
7.2 Connecting the cables....................................................................................................................................... 12
7.3 Pipe length and the elevation ............................................................................................................................ 12
7.4 Air purging of the piping and indoor unit ............................................................................................................ 12
7.5 Pumping down (Re-installation)......................................................................................................................... 14
7.6 Re-air purging (Re-installation).......................................................................................................................... 15
7.7 Balance refrigerant of the 2-way, 3-way valves ................................................................................................. 16
7.8 Evacuation......................................................................................................................................................... 17
7.9 Gas charging ..................................................................................................................................................... 18
8. Operation characteristics ...................................................................................................................... 19
8.1 ............................................................ ............................................................................ 19
8.2 ........................................................................................................................................ 20
9. Electronic function................................................................................................................................. 21
9.1 Abbreviation ...................................................................................................................................................... 21
9.2 Display function ................................................................................................................................................. 21
9.3 Protection .......................................................................................................................................................... 21
9.4 Fan-Only Mode.................................................................................................................................................. 22
9.5 Cooling Mode .................................................................................................................................................... 22
9.6 Drying mode ...................................................................................................................................................... 24
9.7 Heating mode .................................................................................................................................................... 24
9.8 Auto mode function ........................................................................................................................................... 27
9.9 Forced operation function.................................................................................................................................. 28
9.10 Action of 4-way valve ...................................................................................................................................... 28
9.11 Two speeds outdoor fan function..................................................................................................................... 28
9.12 Timer function.................................................................................................................................................. 29
9.13 Sleep function mode........................................................................................................................................ 29
9.14 Auto-Restart function....................................................................................................................................... 29
9.15 Ionizer/Plasma dust collector function(optional) .............................................................................................. 30
9.16 Outdoor chassis heating cable ...................................................................................................................... 30
10. Troubleshooting ................................................................................................................................... 30
10.1 Indoor Unit Error Display ................................................................................................................................. 32
10.2 Diagnosis and Solution.................................................................................................................................... 33
10.3 Key parts checking. ......................................................................................................................................... 36

1
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 unit, be sure to read
this service manual at first.
1.2 Warning
Installation
Do not use a defective or underrated
circuit breaker. Use this appliance on a
dedicated circuit.
There is risk of fire or electric shock.
For electrical work, contact the
dealer, seller, a qualified electrician, or an
Authorized service center.
Do not disassemble or repair the product,
thereisriskoffireorelectricshock.
Always ground the product.
There is risk of fire or electric shock.
Install the panel and the cover of
control box securely.
There is risk of fire of electric shock.
Always install a dedicated circuit and
breaker.
Improper wiring or installation may cause
fore or electric shock.
Use the correctly rated breaker of
fuse.
There is risk of fire or electric shock.
Do not modify or extend the power
cable.
There is risk of fire or electric shock.
Do not install, remove, or reinstall
the unit by yourself(customer).
There is risk of fire, electric shock, explosion,
or injury.
Be caution when unpacking and
installing the product.
Sharp edges could cause injury, be especially
careful of the case edges and the fins on the
condenser and evaporator.
For installation, always contact the
dealer or an Authorized service center.
There is risk of fire, electric shock, explosion,
or injury.
Do not install the product on a
defective installation stand.
It may cause injury, accident, or damage to
the product.
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.
Do not let the air conditioner run for
a long time when the humidity is very high and
a door or a window is left open.
Moisture may condense and wet or damage
furniture.
Take care to ensure that power cable
could not be pulled out or damaged during
operation.
There is risk of fire or electric shock.
Do not place anything on the power
cable.
There is risk of fire or electric shock.
Do not plug or unplug the power
supply plug during operation.
There is risk of fire or electric shock.
Do not touch (operation) the product
with wet hands.
There is risk of fire or electric shock.
Do not place a heater or other
appliance near the power cable.
There is risk of fire and electric shock.
Do not allow water to run into
electric parts.
It may cause fire, failure of the product, or
electric shock.
Do not store or use flammable gas or
combustible near the product.
There is risk of fire or failure of product.
Do not use the product in a tightly
closed space for a long time.
Oxygen deficiency could occur.
When flammable gas leaks, turn off
the gas and open a window for ventilation
before turn the product on.
Do not use the telephone or turn switches on
or off.
There is risk of explosion or fire.
If strange sounds, or small or smoke

2
comes from product. Turn the breaker off or
disconnect the power supply cable.
There is risk of electric shock or fire.
Stop operation and close the window
in storm or hurricane. If possible, remove the
product from the window before the hurricane
arrives.
There is risk of property damage, failure of
product, or electric shock.
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 (flooded
or submerged), contact an Authorized service
center.
There is risk of fire or electric shock.
Be caution that water could not
enter the product.
There is risk of fire, electric shock, or
product damage.
Ventilate the product from time to
time when operating it together with a stove,
etc.
There is risk of fire or electric shock.
Turn the main power off when
cleaning or maintaining the product.
There is risk of electric shock.
When the product is not be used for
a long time, disconnect the power supply plug
or turn off the breaker.
There is risk of product damage or failure, or
unintended operation.
Take care to ensure that nobody
could step on or fall onto the outdoor unit.
This could result in personal injury and
product damage.
CAUTION
Always check for gas (refrigerant)
leakage after installation or repair of product.
Low refrigerant levels may cause failure of
product.
Install the drain hose to ensure that
water is drained away properly.
A bad connection may cause water leakage.
Keep level even when installing the
product.
To avoid vibration of water leakage.
Do not install the product where the
noise or hot air from the outdoor unit could
damage the neighborhoods.
It may cause a problem for your neighbors.
Use two or more people to lift and
transport the product.
Avoid personal injury.
Do not install the product where it
will be exposed to sea wind (salt spray)
directly.
It may cause corrosion on the product.
Corrosion, particularly on the condenser and
evaporator fins, could cause product malfunction or
inefficient operation.
Operational
Do not expose the skin directly to
cool air for long periods of time. (Do not sit in
the draft).
This could harm to your health.
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.
Do not block the inlet or outlet of air
flow.
It may cause product failure.
Use a soft cloth to clean. Do not use
harsh detergents, solvents, etc.
There is risk of fire, electric shock, or
damage to the plastic parts of the product.
Do not touch the metal parts of the
product when removing the air filter. They are
very sharp.
There is risk of personal injury.
Do not step on pr put anything on the
product. (outdoor units)
There is risk of personal injury and failure of
product.
Always insert the filter securely.
Clean the filter every two weeks or more often
if necessary.
A dirty filter reduces the efficiency of the air
conditioner and could cause product malfunction or
damage.
Do not insert hands or other object
through air inlet or outlet while the product is
operated.
There are sharp and moving parts that could

3
cause personal injury.
Do not drink the water drained from
the product.
It is not sanitary could cause serious health
issues.
Use a firm stool or ladder when
cleaning or maintaining the product.
Becarefulandavoidpersonalinjury.
Replace the all batteries in the
remote control with new ones of the same type.
Do not mix old and mew batteries or different
types of batteries.
There is risk of fire or explosion.
Do not recharge or disassemble the
batteries. Do not dispose of batteries in a fire.
They may burn of explode.
If the liquid from the batteries gets
onto your skin or clothes, wash it well with
cleanwater.Donotusetheremoteofthe
batterieshaveleaked.
The chemical in batteries could cause burns
or other health hazards

4
2. Function
When the power supply is
interrupted and then restore, the air
conditioners automatically restore
the previous function setting.
BLDC fan motor
Maintain the room temperature in accordance w
ith the setting temperature.
The mode can be change by the room temperature.
The louver can be set at the desired position or
swing up and down automatically
The function is usually used in rainy days in
springtime or damp areas.
The fan is turn to low speed (cooling/heating).
The unit will be turn off at the seventh hour.
The unit will decide the louver direction according to
operation mode.
Turbo wind, high, med, low, breeze.
Restarting is for approx. 3 minutes..
Prevent the water being f
r
ozen on evaporator by sensing
the evaporator pipe temperature in cooling mode
Room temperature sensor.
Pipe temperature sensor.
Indoor unit
Operation by remote controller
Sensing by room temperature
Room temperature control
Anti-freezing control in cooling
TimeDelaySafetycontrol
Indoor fan speed control
Two-direction air vane
Sleep mode auto control
Independent dehumidification
Air flow Direction control
Auto mode
Temp. Compensation Flexible wiring connection
Auto defrost
Ionizer (Optional)
Anti-cold function
Self-diag. function
Auto-restart function
Prevent the cold wind at the
beginning of unit start.

5
It protects the valves and prevents water from dripping.
The unit has 3 mins delay between continuously ON/OFF operations.
Outdoor unit
Power relay control
The hydrophilic fin can improve the heating efficiency at operation mode.
Hydrophilic aluminum fin
It is only operated in the heating operation mode except defrosting operation.
Anti-rust cabinet
Valve protection cover
4 way valve control
Made from electrolytic zinc steel sheet and anti-
rust coated components.
Low noise air flow system
Bird tail propeller fan makes the outdoor unit run more quietly.
Discharge pipe temperature protect
EEV control
Low ambient cooling function (optional)
BLDC fan motor

8
Indoor MTN A256DV
Outdoor MTG A256DV
Power supply Ph-V-Hz 1, 220-240V~, 50/60Hz
Max. input consumption W 2050
Max. current A 9.5
Compressor
Model DA110S1C-30FZ
Type Twin-Rotary DC inverter
Brand GMCC
Capacity W 3200
Input W 850
Rated current(RLA) A 5.8
Thermal protector CS-74
Capacitor uF No
Refrigerant oil ml 500
Indoor fan motor
Model WZDK30-38G
Brand Welling/Panasonic
Output W 30
Speed r/min 1230/1120/880/700/600/550
Indoor air flow (Hi/Mi/Lo) m3/h 850/750/620
Indoor noise level (Hi/Mi/Lo) dB(A) 41/33/27
Indoor unit
Dimension (W*H*D) mm 850*305*225
Packing (W*H*D) mm 945*385*313
Net/Gross weight Kg 10.5/13.5
Outdoor fan motor
Model WZDK35-38G
Brand Welling/Panasonic
Output W 35
Speed r/min 850/580
Outdoor air flow m3/h 2200
Outdoor noise level dB(A) 53
Outdoor unit
Dimension(W*H*D) mm 760*590*285
Packing (W*H*D) mm 887*645*355
Net/Gross weight Kg 37/40
Refrigerant type R410A g 1100
Refrigerant piping
Liquid side/ Gas side mm Ф6.35/Ф12.7
Max. refrigerant pipe length m 20
Max. difference in level m 8
Operation temp 17 ~ 30
Ambient temp -15 ~ 50
The above design and specifications are subject to change without prior notice for product improvement.

9
5. Refrigerant cycle diagram