Mitsubishi Electric PUHY-P200 How to use

Models PUHY-P200, P250, P300, P350, P400YGM-A
PUHY-P450, P500, P550, P600, P650YGM-A
PUY-P200, P250, P300, P350YGM-A
Service Handbook
AIR CONDITIONERS CITY MULTI

Contents
1Read Before Servicing ................................................................ 6
[1] Items to Be Checked .............................................................. 6
[2] Necessary Tools and Materials .............................................. 7
[3] Piping Materials ...................................................................... 8
[4] Storage of Piping Material ...................................................... 10
[5] Piping Machining .................................................................... 11
[6] Brazing.................................................................................... 12
[7] Airtightness Test ...................................................................... 13
[8] Vacuuming .............................................................................. 13
[9] Vacuum Drying........................................................................ 14
[ 10 ] Changing Refrigerant.............................................................. 15
[ 11 ] Remedies to be taken in case of a refrigerant leak................ 15
[ 12 ] Characteristics of the Conventional and the New Refrigerants .. 16
[ 13 ] Notes on Refrigerating Machine Oil........................................ 17
2Restrictions .................................................................................. 18
[1] Electrical Work & M-NET control ............................................ 18
[2] Types of Switch Setting and Address Setting ........................ 19
[3] Examples of system connection ............................................ 21
[4] Restrictions on Refrigerant Piping Length.............................. 35
3Components of the Outdoor Unit ................................................ 37
[1] Appearance of the Components and Refrigerant Circuit........ 37
[2] Control Box ............................................................................ 43
[3] Circuit Board .......................................................................... 45
4Remote Controller........................................................................ 49
[1] Functions and Specifications of MA and ME Remote Controllers .... 49
[2] Group Setting and Interlocking Settings that are Made on
the ME Remote Controller .................................................... 50
[3] Interlocking Setting that is Made on the MA Remote Controller ...... 53
[4] Switching to the built-in Thermo on the remote controller...... 54
5Electrical Wiring Diagram ............................................................ 55
[1] PUHY-P200, P250, P300, P350, P400YGM-A / PUY-P200, P250, P300, P350YGM-A .. 55
[2] PUHY-P450, P500, P550, P600, P650YGM-A .............................. 56
[3] Power Dispatching Extension Unit for the Transmission Lines ........ 57
6Refrigerant Circuit ........................................................................ 58
[1] Refrigerant Circuit Diagram .................................................... 58
[2] Functions of Principal Parts.................................................... 62
7Control.......................................................................................... 64
[1] Dip Switch Functions and Their Factory Settings .................. 64
[2] Controlling the Outdoor Unit .................................................. 69
[3] Operation Flow Chart ............................................................ 76
8Test Run ...................................................................................... 81
[1] Check Items before Test Run.................................................. 81
[2] Test Run Method .................................................................... 81
[3] Operating Characteristics and Refrigerant Amount................ 82
[4] Adjustment and Judgment of Refrigerant Amount ................ 82
[5] Refrigerant Volume Adjustment Mode Operation .................. 84
[6] Symptoms that do not Signify Problems ................................ 86
[7] Standard Operation Data (Reference Data) .............................. 87
9Troubleshooting............................................................................ 95
[1] Check Code List .................................................................... 95
[2] Responding to Error Display on the Remote Controller ........ 98
[3] Investigation of Transmission Wave Shape/Noise .................. 131
[4] Troubleshooting of Principal Parts .......................................... 134
[5] Refrigerant Leak .................................................................... 151
[6] Compressor Replacement Instructions (only P450-P650 types) .... 153
[7] Collecting the Cooling Liquid from the Accumulator (Only P450-P650 types) .. 154
0LED display .................................................................................. 155
[1] LED Monitor Display .............................................................. 155

Safety Precautions
Symbols used in the text
Warning:
Failure to follow all instructions may result in serious personal injury or death.
Caution:
Failure to follow all instructions may result in personal injury or damage to the unit.
Symbols used in the illustrations
: Indicates an action that must be avoided.
: Indicates that important instructions must be followed.
: Indicates a part which must be grounded.
: Beware of electric shock (This symbol is displayed on the main unit label.) <Color : Yellow>
Warning : Carefully read the labels affixed to the main unit.
Before installing the unit, be sure to carefully read all of the following safety precautions.
These precautions provide important information regarding safety. Be sure to follow them to ensure safety.
After reading this handbook, hand it over to those who will be using the unit.
The user of the unit should keep this manual at hand and make it available to those who will be performing
repairs or relocating the unit.
Also, make it available to the new user when the user changes hands.
Be sure to carefully follow each step in this
handbook when installing the unit.
•Improper installation may result in water leak,
electric shock, smoke or fire.
Securely attach the terminal cover (panel) on the
unit.
•If installed improperly, dust and/or water may enter
the unit and present a risk of electric shock, smoke,
or fire.
Only use Refrigerant R410A as indicated on the
unit when installing or relocating the unit.
•The use of any other refrigerant or an introduction of
air into the unit circuit may cause the unit to run an
abnormal cycle and cause the unit to burst.
Do not make any changes or modifications to the
unit. In case of problems, consult the dealer.
•If repairs are not made properly, the unit may leak
water and present a risk of electric shock, or it may
produce smoke or cause fire.
Have all electrical work performed by a licensed
electrician according to the local regulations and
the instructions given in this manual. Secure a
circuit designated exclusively to the unit.
•Improper installation or a lack of circuit capacity may
cause the unit to malfunction or present a risk of
electric shock, smoke, and fire.
Have the unit professionally installed.
•Improper installation by an unqualified person may
result in water leak, electric shock, or fire.
Only use specified cables for wiring. Securely
connect each cable, and make sure that the cables
are not straining the terminals.
•Cables not connected securely and properly may
generate heat and cause fire.
Place the unit on a stable, level surface that
withstands the weight of the unit to prevent the
unit from tipping over or falling causing injury as a
result.
Take necessary safety measures against typhoons
and earthquakes to prevent the unit from falling
over.
- 1 -

When relocating the air conditioner, consult the
dealer or a specialist.
•Improper installation may result in water leak,
electric shock, or fire.
•Consult the dealer for necessary measures to take.
After completing the service work, check for a
refrigerant gas leak.
•If leaked gas refrigerant is exposed to a heart
source such as fan heater, stove, and electric grill,
noxious gases may form.
In the event of a refrigerant gas leak, provide
adequate ventilation to the room.
•If leaked refrigerant gas is exposed to a heat source,
noxious gases may form.
With All-Fresh type air conditioners, outdoor air
may be directly blown into the room upon thermo
off. Take this into consideration when installing the
unit.
•Direct exposure to outdoor air may present a health
hazard, and it may also cause food items to
deteriorate.
When installing the unit in a small room, safeguard
against hypoxia that results from leaked refrigerant
reaching the threshold level.
Do not touch the fins on the heat exchanger with
bare hands: they are sharp and dangerous.
Precautions for Handling Units for Use with R410A
Caution
Warning : Carefully read the labels affixed to the main unit.
Do not try to defeat the safety features of the
devices, and do not change the settings.
•Defeating the safety features on the unit such as the
pressure switch and temperature switch or using
parts other than those specified by Mitsubishi
Electric may result in fire or explosion.
Use refrigerant pipes made of C1220 phosphorus
deoxidized copper categorized under H3000
(Copper and Copper Alloy Seamless Pipes and
Tubes), a standard set by JIS. Keep the inner and
outer surfaces of the pipes clean and free of
contaminants such as sulfur, oxides, dust/dirt,
shaving particles, oils, and moisture.
•Contaminants inside the refrigerant piping will cause
the refrigerant oil to deteriorate.
Do not use the following tools that have been used
with the conventional refrigerants.Prepare tools
that are for exclusive use with R410A.
(Gauge manifold, charging hose, gas leak detector,
reverse-flow check valve, refrigerant charge base,
vacuum gauge, and refrigerant recovery
equipment.)
•If refrigerant and /or refrigerant oil left on these tools
are mixed in with R410A, or if water is mixed with
R410A, it will cause the refrigerant to deteriorate.
•Since R410A does not contain chlorine, gas-leak
detectors for conventional refrigerators will not work.
Only use specified parts.
•Have the unit professionally installed.
Improper installation may cause water leak, electric
shock, smoke, or fire.
Use a vacuum pump with a reverse-flow-check
valve.
•If other types of valves are used, the vacuum pump
oil will flow back into the refrigerant cycle and cause
the refrigerator oil to deteriorate.
Do not use the existing refrigerant piping
•The old refrigerant and refrigerator oil in the existing
piping contain a large amount of chlorine, which will
cause the refrigerator oil in the new unit to
deteriorate.
•R410A is a high-pressure refrigerant, and the use of
the existing piping may result in bursting.
- 2 -

Before Installing the Unit
Warning
Caution
Store the piping to be used during installation
indoors, and keep both ends of the piping sealed
until immediately before brazing. (Keep elbows and
other joints wrapped in plastic.)
•If dust, dirt, or water enters the refrigerant cycle, it
may cause the oil in the unit to deteriorate or may
cause the compressor to malfunction.
Use a small amount of ester oil, ether oil, or
alkylbenzene to coat flares and flange connections.
•A large amount of mineral oil will cause the
refrigerating machine oil to deteriorate.
Do not use a charging cylinder.
•The use of charging cylinder will change the
composition of the refrigerant and lead to power
loss.
Exercise special care when handling the tools.
•An introduction of foreign objects such as dust, dirt,
or water into the refrigerant cycle will cause the
refrigerating machine oil to deteriorate.
Only use R410A refrigerant.
•The use of refrigerants containing chlorine (i.e. R22)
will cause the refrigerant to deteriorate.
Use liquid refrigerant to charge the system.
•Charging the unit with gas refrigerant will cause the
refrigerant in the cylinder to change its composition
and will lead to a drop in performance.
Do not install the unit in a place where there is a
possibility of flammable gas leak.
•Leaked gas accumulated around the unit may start a
fire.
Do not use the unit to preserve food, animals,
plants, artifacts, or for other special purposes.
•The unit is not designed to provide adequate
conditions to preserve the quality of these items.
When installing the unit in a hospital, take
necessary measures against noise.
•High-frequency medical equipment may interfere
with the normal operation of the air conditioning unit
or the air conditioning unit may interfere with the
normal operation of the medical equipment.
Do not use the unit in an unusual environment.
•The use of the unit in the presence of a large
amount of oil, steam, acid, alkaline solvents, or
special types of sprays may lead to a remarkable
drop in performance and/or malfunction and
presents a risk of electric shock, smoke, or fire.
•The presence of organic solvents, corroded gas
(such as ammonia, sulfur compounds, and acid)
may cause gas or water leak.
Do not place the unit on or over things that may
not get wet.
•When humidity level exceeds 80% or when the
drainage system is clogged, indoor units may drip
water.
•Installation of a centralized drainage system for the
outdoor unit may also need to be considered to
prevent water drips from the outdoor units.
- 3 -

Before Installing (Relocating) the Unit or Performing Electric Work
Caution
Do not spray water on the air conditioners or
immerse the air conditioners in water.
•Water on the unit presents a risk of electric shock.
Install a breaker for current leakage at the power
source to avoid the risk of electric shock.
•Without a breaker for current leakage, there is a risk
of electric shock, smoke, or fire.
Use wires that are specified in the installation
manual.
•The use of other types of wires presents a risk of
electrical current leak, electric shock, smoke, or fire.
Periodically check the platform on which the unit is
placed for damage to prevent the unit from falling.
•If the unit is left on a damaged platform, it may
topple over, causing injury.
Ground the unit.
•Do not connect the grounding on the unit to gas
pipes, water pipes, lightning rods, or the grounding
terminals of telephones. Improper grounding
presents a risk of electric shock, smoke, fire, or the
noise caused by improper grounding may cause the
unit to malfunction.
Use breakers and fuses (electrical current breaker,
remote switch <switch + Type-B fuse>, molded
case circuit breaker) with a proper current
capacity.
•The use of large-capacity fuses, steel wire, or
copper wire may damage the unit or cause smoke or
fire.
When installing draining pipes, follow the
instructions in the manual, and make sure that they
properly drain water so as to avoid dew
condensation.
•If not installed properly, they may cause water leaks
and damage the furnishings.
Make sure the wires are not subject to tension.
•If the wires are too taut, they may break or generate
heat and/or smoke and cause fire.
Exercise caution when transporting products.
•Do not try to move equipments over 20kg (approx.
44 lbs.) alone.
•Do not use the PP bands used on some packages
for transportation.
•Wear protective gloves to avoid injury caused by
touching the fins on the heat exchanger with bare
hands.
•When using a suspension bolt to transport the heat-
source unit, use a four-point suspension. A three-
point suspension does not provide adequate stability
and presents a risk of accidents.
Properly dispose of the packing materials.
•Things such as nails and wood pieces may be
included in the package. Dispose of them properly to
prevent injury.
•Plastic bags present a choking hazard to children.
Tear up the plastic bags before disposing of them to
prevent accidents.
- 4 -

Before the Test Run
Caution
Turn on the unit at least 12 hours before the test
run.
•Keep the unit on throughout the season.
Turning the unit off during the season may cause
problems.
Do not turn off the power immediately after
stopping the unit.
•Allow for at least five minutes before turning off the
unit; otherwise, the unit may leak water or
experience other problems.
Do not operate the unit without panels and safety
guards in their proper places.
•They are there to keep the users from injury from
accidentally touching rotating, high-temperature, or
high-voltage parts.
Do not touch the refrigerant pipes with bare hands
during and immediately after operation.
•Depending on the state of the refrigerant in the
system, certain parts of the unit such as the pipes
and compressor may become very cold or hot and
may subject the person to frost bites or burning.
Do not operate switches with wet hands to avoid
electric shock.
Do not operate the unit without air filters.
•Dust particles in the air may clog the system and
cause malfunction.
- 5 -

- 6 -
¡¡ Read Before Servicing
[1] Items to Be Checked
1. Verify the type of refrigerant used by the unit to be serviced.
Refrigerant Type : R410A
2. Check the symptom exhibited by the unit to be serviced.
Look in this service handbook for symptoms relating to the refrigerant cycle.
3. Be sure to carefully read the Safety Precautions at the beginning of this document.
4. Prepare necessary tools: Prepare tools exclusive for use with each refrigerant type.
Refer to P7 for more information.
5. If the refrigerant circuit is opened (to repair a gas leak etc.), the dryer needs to be replaced.
Only use the dryer designed specifically for Citi Multi YGM-A. The use of other dryers may result in malfunctions.
✻Replace the dryer after completing all the repairs on the refrigerant circuit.
(If left exposed to air, the dryer will absorb moisture. Replace the dryer as quickly as possible after removing
the old one.)
✻When all of the following conditions are met, the replacement of drier is not necessary.
(1) Do not leave the refrigerant circuit longer than 2 hours.
(2) Cover the opening end with a cap or tape to keep moisture from entering.
(3) Also cover the opening end of the new part with a cap or tape
(4) Do not perform the task in the rain.
(5) Evacuate the refrigerant circuit as specified.
6. Verification of the connecting pipes: Verify the type of refrigerant used for the unit to be
moved or replaced.
• Use pipes made of phosphorus deoxidized copper. Keep the inner and outer surfaces of the pipes clean and
free of contaminants such as sulfur, oxides, dust/dirt, shaving particles, oils, and moisture.
• Contaminants inside the refrigerant piping will cause the refrigerant oil to deteriorate.
7. If there is a gas leak or if the remaining refrigerant is exposed to an open flame, a noxious gas
hydrofluoric acid may form. Keep workplace well ventilated.
CAUTION
1. Install new pipes immediately after removing old ones to keep moisture out of the refrigerant circuit.
2. Chloride in some types of refrigerants such as R22 will cause the refrigerating machine oil to
deteriorate.

- 7 -
[2] Necessary Tools and Materials
Prepare the following tools and materials necessary for installing and servicing the unit.
[Necessary tools for use with R410A (Adaptability of tools that are for use with R22 and R407C)]
1. To be used exclusively with R410A (not to be used if used with R22 or R407C)
Tools/Materials NotesUse
Gauge Manifold
Charging Hose
Refrigerant Recovery Equipment
Refrigerant Cylinder
Refrigerant Cylinder Charging Port
Flare Nut
Evacuating, refrigerant charging
Evacuating, refrigerant charging
Refrigerant recovery
Refrigerant charging
Refrigerant charging
Connecting the unit to piping
5.09MPa on the High-pressure side.
Hose diameter larger than the conventional ones.
Write down the refrigerant type.
Pink in color at the top of the cylinder.
Hose diameter larger than the conventional ones.
Use Type-2 Flare nuts.
(That are in compliance with JIS B 8607).
2. Tools and materials that may be used with R410A with some restrictions
Tools/Materials NotesUse
Gas leak detector
Vacuum Pump
Flare Tool
Refrigerant Recovery Equipment
Detection of gas leaks
Vacuum drying
Flare machining of piping
Recovery of refrigerant
The ones for HFC type refrigerant may be used.
May be used if a reverse flow check adaptor is
attached.
Changes have been made in the flare machining
dimension. Refer to the next page.
May be used if designed for use with R410A.
3. Tools and materials that are used with R22 or R407C that can also be used with R410A
Tools/Materials NotesUse
Vacuum Pump with a Check valve
Bender
Torque Wrench
Pipe Cutter
Welder and Nitrogen Cylinder
Refrigerant Charging Meter
Vacuum Gauze
Vacuum drying
Bending pipes
Tightening flare nuts
Cutting pipes
Welding pipes
Refrigerant charging
Checking vacuum degree
Only ø 12.70 (1/2”) and ø 15.88 (5/8”) have a
larger flare machining dimension.
4. Tools and materials that must not be used with R410A
Tools/Materials NotesUse
Charging Cylinder Refrigerant Charging Must not be used with R410A-type units.
Tools for R410A must be handled with special care; keep moisture and dust from entering the
cycle.

Type-O pipes Soft copper pipes (annealed copper pipes)
They can be bent easily with hands.
Type-1/2H pipes Hard copper pipes (straight pipes)
Stronger than type-O pipes of the same radial thickness.
- 8 -
[3] Piping Materials
NOOK
New Piping Existing Piping
Do not use the existing piping!
<Types of copper pipe>
•The distinction between type-O and type-1/2H pipes is made based on the strength of the pipes themselves.
•Type-O pipes are soft and can easily be bent with hands.
•Type-1/2H pipes are considerably stronger than type-O pipes of the same radial thickness.
Use pipes made of phosphorus deoxidized copper.
Since the operation pressure of the units that use R410A is higher than that of the units for use with R22, use
pipes with at least the radial thickness specified in the chart below.
(Pipes with a radial thickness of 0.7 mm or less may not be used.)
Maximum Operation Pressure Applicable Refrigerants
3.45 MPa
4.30 MPa
R22, R407C etc.
R410A
<Types of Copper Pipes (Reference)>
✻ Use pipes that meet the local standards.
Type-O pipes
Type-1/2H or
H pipes
Size(mm) Size(inch) Radial Thickness(mm) Type
ø 6.35
ø 9.52
ø 12.7
ø 15.88
ø 19.05
ø 22.2
ø 25.4
ø 28.58
ø 31.75
1/4”
3/8”
1/2”
5/8”
3/4”
7/8”
1”
1 1/8”
1 1/4”
0.8t
0.8t
0.8t
1.0t
1.0t
1.0t
1.0t
1.0t
1.1t
<Piping Materials/Radial Thickness>
✻ Although it was possible to use type-O for pipes with a size of up to ø19.05 (3/4”) with conventional refriger-
ants, use type-1/2H pipes for units that use R410A. (Type-O pipes may be used if the pipe size is ø19.05 and
the radial thickness is 1.2t.)
✻The table shows the standards in Japan. Using this table as a reference, choose pipes that meet the local
standards.