MDV MS1Ai-09HRFN1 User manual

1ASFI-1103-A
SERVICE MANUAL
MDV AIRCONDITIONER
EUROPE MARKET
SPLIT WALL-MOUNTED TYPE
1A INVERTER SERIES

CONTENTS
1. Precaution .................................................................................................................................................... 1
1.1 Safety Precaution.......................................................................................................................... 1
1.2 Warning......................................................................................................................................... 1
2. Function........................................................................................................................................................ 6
3. Dimension .................................................................................................................................................... 9
3.1 Indoor Unit..................................................................................................................................... 9
3.2 Outdoor Unit................................................................................................................................ 10
4. Refrigerant Cycle Diagram ........................................................................................................................11
5. Wiring Diagram .......................................................................................................................................... 12
5.1 Indoor Unit................................................................................................................................... 12
5.2 Outdoor Unit................................................................................................................................ 14
6. Installation details...................................................................................................................................... 17
6.1 Wrench torque sheet for installation........................................................................................... 17
6.2 Connecting the cables ................................................................................................................ 17
6.3 Pipe length and the elevation ..................................................................................................... 18
6.4 Air purging with vacuum pump.................................................................................................... 20
6.5 Pumping down (Re-installation).................................................................................................. 21
6.6 Re-air purging (Re-installation)................................................................................................... 22
6.7 Balance refrigerant of the 2-way, 3-way valves.......................................................................... 23
6.8 Evacuation .................................................................................................................................. 24
6.9 Gas charging............................................................................................................................... 25
7. Operation characteristics ......................................................................................................................... 26
8. Electronic function.................................................................................................................................... 27
8.1 Abbreviation ................................................................................................................................ 27
8.2 Display function........................................................................................................................... 27
8.3 Main Protection........................................................................................................................... 28
8.4 Operation Modes and Functions................................................................................................. 29
9. Troubleshooting......................................................................................................................................... 40
9.1 Indoor Unit Error Display............................................................................................................. 40
9.2 Diagnosis and Solution............................................................................................................... 41

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, there is risk of fire or electric shock.
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.

2
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.

3
If strange sounds, or small or smoke 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.
It can avoid vibration of water leakage.
Do not install the product where the noise or hot air from the outdoor unit could damage

4
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 or 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 cause personal injury.
Do not drink the water drained from the product.

5
It is not sanitary could cause serious health issues.
Use a firm stool or ladder when cleaning or maintaining the product.
Be careful and avoid personal injury.
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 clean
water. Do not use the remote of the batteries have leaked.
The chemical in batteries could cause burns or other health hazards
The designs, and information in this book are subject to change without notice for product improvement.

6
2. Function
Model Names of Indoor/Outdoor Units
3D
Inverter
Capacity
Indoor units
Outdoor units
9k
MS1Ai
-09HRFN1
MOC3i
-09HFN1
12k
MS1Ai
-12HRFN1
MOC3i
-12HFN1

7
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 unit will decide the louver direction according
to operation mode.
Turbo wind, high, med, low, auto
Prevent the water being frozen on evaporator by
checking the evaporator coil temperatur
Indoor unit
Operation by remote controller
Anti-freezing control in cooling mode
Time Delay Safety control
Indoor fan speed control
Two-direction air vane
Sleep mode auto control
Independent dehumidification
Air flow Direction control
Auto mode
Flexible wiring connection
Auto defrost
Anti-cold function
Self-diag. function
Auto-restart
Ionizer (Optional)
Prevent the cold wind at the
beginning of unit start.
Follow me
Golden fin (Optional)
Silence operation
Concealed display
Self clean function

8
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.
Valve protection cover
4 way valve control
Made from electrolytic zinc steel sheet and anti-rust coated components.
Low noise air flow system
Compressor crank case heater
Driving heating at -20℃for outdoor units
Anti-rust cabinet

9
3. Dimension
3.1 Indoor Unit
For MS1Ai-09HRFN1, MS1Ai-12HRFN1 units,
Model
Dimension (mm)
W
H
D
MS1Ai
-09HRFN1
830
316
250
MS1Ai
-12HRFN1
830
316
250

10
3.2 Outdoor Unit
Model
W
H
D
B
C
F
MOC3i
-09HFN1
MOC3i
-12HFN1
760
590
285
530
290
63

11
4. Refrigerant Cycle Diagram

12
5. Wiring Diagram
5.1 Indoor Unit
MS1Ai-09HRFN1 MS1Ai-12HRFN1

14
5.2 Outdoor Unit
MOC3i-09HFN1 MOC3i-12HFN1

17
6. Installation details
6.1 Wrench torque sheet for installation
Outside diameter
Torque
Additional
tightening torque
mm
inch
N.cm
N.cm
Ф6.35
1/4
1500
(153kgf.cm)
1600
(163kgf.cm)
Ф9.52
3/8
2500
(255kgf.cm)
2600
(265kgf.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
0.75
>6 and ≤10
1.0
>10 and ≤16
1.5
>16 and ≤25
2.5
The cable size and the current of the fuse or switch are determined by the maximum current indicated
on the nameplate which located on the side panel of the unit. Please refer to the nameplate before
selecting the cable, fuse and switch.

18
6.3 Pipe length and the elevation
The pipe length and refrigerant amount:
Model
Connective pipe
length
Air purging
Additional amount of
refrigerant
All
Less than 5m
Use vacuum
pump
------------------
MS1Ai
-09HRFN1
MS1Ai
-12HRFN1
More than 5m
Use vacuum
pump
(Pipe length –5) × 20g/m
Model
Standard
length
(m)
Max.
Elevation
B (m)
Max.
Length
A (m)
MS1Ai
-09HRFN1 MS1Ai-12HRFN1
5
8
20
Caution:
Capacity test is based on standard length and maximum allowance length is based on system
reliability. Oil trap should be installed per 5-7 meters.

20
6.4 Air purging with vacuum pump
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.
●Water may lead to corrosion of parts in the refrigerant system.
Therefore, the indoor units and the pipes between indoor and outdoor units must be leak tested and
evacuated to remove gas and moisture from the system.
Air purging with vacuum pump
(Indoor unit) (Liquid side)
(Gas side)
Vacuum
pump
Vacuum
pump
adaptor
Lo Hi
Handle Hi
Two-way valve
Close
Manifold valve
Compound meter Pressure
gauge
-76cmHg
Handle Lo
Charge hose Charge hose
(Outdoor unit)
Close
Three-way valve
Procedure
1. Completely tighten the flare nuts of the indoor and outdoor units, connect the manifold valve
charge.
2. Connect the charge hose connection to the vacuum pump.
3. Fully open the handle Lo of the manifold valve.
4. Operate the vacuum pump to evacuate. After starting evacuation, slightly loose the flare nut of the
Lo valve on the gas pipe side and check the air is entering. (Operation noise of the vacuum pump
changes and a compound meter indicates 0 stead of minutes)
5. After the evacuation is complete, fully close the handle Lo valve of the manifold valve and stop the
operation of the vacuum pump. Make evacuation for 15 minutes or more and check the compound
meter indicates -76cmHg.
6. Turn the stem of the Hi valve about 45°counterclockwise for 6 or 7seconds after the gas coming

21
out, then tighten the flare nut again. Make sure the pressure display in the pressure indicator is a
little higher than the atmosphere pressure.
7. Remove the charge hose from the Lo pressure charge hose.
8. Fully open the Hi and Lo packed valve.
9. Securely tighten the cap of the packed valve.
Gas leak check
Soap water method
Apply soap water or a liquid neutral detergent on the indoor unit connections or outdoor unit
connections by a soft brush to check for leakage of the connecting points of the piping. If bubbles
come out, the pipes have leakage.
6.5 Pumping down (Re-installation)
Procedure
1. Confirm that both the 2-way and 3-way valves are set to the opened position.
Remove the valve stem caps and confirm that the valve stems are in the opened position.
Be sure to use a hexagonal wrench to operate the valve stems.
2. Operate the unit for 10 to 15 minutes.
3. Stop operation and wait for 3 minutes, then connect the charge set to the service port of the 3-way
valve.
Connect the charge hose with the push pin to the gas service port.
4.Air purging of the charge hose.

22
Open the low-pressure valve on the charge set slightly to purge air from the charge hose.
5. Set the 2-way valve to the close position.
6. Operate the air conditioner at the cooling cycle and stop it when the gauge indicates 0.1MPa.
7. 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 amount the 2-way and 3-way valve’s stem nuts and service port caps.
Use a torque wrench to tighten the service port cap.
Be sure to check for gas leakage.
6.6 Re-air purging (Re-installation)
Procedure:
1. Confirm that both the 2-way and 3-way valves are set to the closed position.
2. Connect the charge set and a charging cylinder to the service port of the 3-way valve.
Leave the valve on the charging cylinder closed.
3. Air purging.
Open the valves on the charging cylinder and the charge set. Purge the air by loosening the flare nut on
the 2-way valve approximately 45’ for 3 seconds then closing it for 1 minute; repeat 3 times.