Mitsubishi Electric PUHY-HP72 How to use

i
Safety Precautions
Please read the following safety precautions carefully before installing the unit to ensure safety.
Make sure that this manual is passed on to the end user to retain for future reference.
Retain this manual for future reference. When the unit is reinstalled or repaired, have this manual available to those who pro-
vide these services. Make sure that this manual is passed on to any future users.
All electric work must be performed by qualified personnel.
Air tightness test must be performed by qualified personnel.
[1] General Precautions
Indicates a risk of death or serious injury.
Indicates a risk of serious injury or structural damage.
General Precautions
Do not use refrigerant other than the type in-
dicated in the manuals provided with the
unit and on the nameplate. Doing so may
cause the unit or pipes to burst, or result in
explosion or fire during use, during repair,
or at the time of disposal of the unit. It may
also be in violation of applicable laws. MIT-
SUBISHI ELECTRIC CORPORATION cannot
be held responsible for malfunctions or ac-
cidents resulting from the use of the wrong
type of refrigerant.
Do not install the unit in a place where large
amounts of oil, steam, organic solvents, or
corrosive gases, such as sulfuric gas, are
present or where acidic/alkaline solutions
or sprays containing sulfur are used fre-
quently. These substances can compro-
mise the performance of the unit or cause
certain components of the unit to corrode,
which can result in refrigerant leakage, wa-
ter leakage, injury, electric shock, malfunc-
tions, smoke, or fire.
Donottrytodefeatthesafetyfeaturesofthe
unit or make unauthorized setting changes.
Forcing the unit to operate the unit by de-
feating the safety features of the devices
such as the pressure switch or the tempera-
ture switch, making unauthorized changes
to the switch settings, or using accessories
other than the ones recommended by Mit-
subishi Electric may result in smoke, fire, or
explosion.
To reduce the risk of shorting, current leak-
age,electricshock,malfunctions,smoke,or
fire, do not splash water on electric parts.
To reduce the risk of electric shock, mal-
functions, smoke or fire, do not operate the
switches/buttons or touch other electrical
parts with wet hands.
To reduce the risk of pipe burst and explo-
sion, do not allow gas refrigerant and refrig-
erant oil to be trapped in the refrigerant
circuit.
To reduce the risk of burns or frost bites, do
nottouch therefrigerant pipes or refrigerant
circuit components with bare hands during
and immediately after operation.
To reduce the risk of burns, do not touch
any electrical parts with bare hands during
or immediately after stopping operation.
To reduce the risk of injury from falling
tools, keep children away while installing,
inspecting, or repairing the unit.
Keep the space well ventilated. Refrigerant
can displace air and cause oxygen starva-
tion. If leaked refrigerant comes in contact
with a heat source, toxic gas may be gener-
ated.

ii
[2] Transportation and Installation
Always replace a fuse with one with the cor-
rect current rating. The use of improperly
rated fuses or a substitution of fuses with
steel or copper wire may result in bursting,
fire or explosion.
To reduce the risk of electric shock, smoke,
and fire due to infiltration of dust and water,
properly install all required covers and pan-
els on the terminal box and control box.
Toreducethe risk ofinjuryfromunits falling
or falling over, periodically check the instal-
lation base for damage.
Consultan authorizedagencyforthe proper
disposal of the unit. Refrigerant oil and re-
frigerant that may be left in the unit pose a
risk of fire, explosion, or environmental pol-
lution.
To reduce the risk of being caught in rotat-
ing parts, electric shock, and burns, do not
operate the unit without all required panels
and guards being installed.
To reduce the risk of injury, do not sit,
stand, or place objects on the unit.
To reduce the risk of water leakage and mal-
functions, do not turn off the power immedi-
ately after stopping operation. Leave the
unit turned on for at least 5 minutes before
turning off the power.
Do not install the unit over things that are
vulnerable to water damage from condensa-
tion dripping.
To reduce the risk of injury, electric shock,
and malfunctions, do not touch or allow ca-
bles to come in contact with the edges of
components.
To reduce the riskof injury, donot touch the
heat exchanger fins or sharp edges of com-
ponents with bare hands.
Always wear protective gears when touch-
ing electrical components on the unit. Sev-
eral minutes after the power is switched off,
residual voltage may still cause electric
shock.
To reduce the risk of electric shock and
burns, always wear protective gear when
working on units.
To reduce the risk of injury, do not insert fin-
gers or foreign objects into air inlet/outlet
grills. If the unit is left on a damaged base, it
may fall and cause injury.
To reduce the risk of injury, always wear
protective gear when working on units.
Do not release refrigerant into the atmo-
sphere. Collect and reuse the refrigerant, or
have it properly disposed of by an autho-
rized agency. Refrigerant poses environ-
mental hazards if released into the air.
Transportation and Installation
Lift the unit by placing the slings at desig-
nated locations. Support the outdoor unit
securely at four points to keep it from slip-
ping and sliding. If the unit is not properly
supported, it may fall and cause personal
injury.
To reduce the risk of injury, do not carry the
product by the PP bands that are used on
some packages.
To reduce the risk of injury, products weigh-
ing 20 kg or more should be carried by two
or more people.

iii
[3] Installation
[4] Piping Work
Installation
Do not install the unit where there is a risk
of leaking flammable gas.
If flammable gas accumulates around the
unit, it may ignite and cause a fire or explo-
sion.
To reduce the risk of injury from coming in
contact with units, install units where they
are not accessible to people other than
maintenance personnel.
To reduce the risk of injury, properly dis-
pose of the packing materials so that chil-
dren will not play with them.
Properly dispose of the packing materials.
Plastic bags pose suffocation hazard to
children.
All drainage work should be performed by
the dealer or qualified personnel according
to the instructions detailed in the Installa-
tion Manual. Improper drainage work may
cause water leakage and resultant damage
to the furnishings.
Remove packing materials from the unit be-
fore operating the unit. Note that some ac-
cessories may be taped to the unit. Properly
install all accessories that are required. Fail-
ing to remove the packing materials or fail-
ing to install required accessories may
result in refrigerant leakage, oxygen depri-
vation, smoke, or fire.
Consult your dealer and take appropriate
measures to safeguard against refrigerant
leakageandresultantoxygenstarvation.An
installation of a refrigerant gas detector is
recommended.
Any additional parts must be installed by
the dealer or qualified personnel. Only use
the parts specified by Mitsubishi Electric.
Installation by unauthorized personnel or
use of unauthorized parts or accessories
may result in water leakage, electric shock,
or fire.
Take appropriate safety measures against
wind gusts and earthquakes to prevent the
unit from toppling over and causing injury.
Toreducethe risk ofinjuryfromunits falling
or falling over, install the unit on a surface
that is strong enough to support its weight.
Do not install the unit over things that are
vulnerable to water damage. Provide an ad-
equate collective drainage system for the
drain water from unit as necessary.
To reduce therisk of damage to the unit and
resultant electric leak and electric shock,
keep small animals, snow, and rain water
from entering the unit by closing the gap in
the pipe and wire access holes.
To reduce the risk of rain water or drain wa-
ter from entering the room and damaging
the interior, drainage work must be per-
formed by your dealer or qualified person-
nel according to the instructions detailed in
the Installation Manual.
Piping Work
To reduce the risk of injury, including frost
bites, that may result from being blasted
with refrigerant, use caution when operat-
ing the refrigerant service valve. If refriger-
ant leaks out and comes in contact with an
open flame, toxic gases may be generated.
To reduce the risk of refrigerant catching
fire and causing burns, remove the refriger-
ant gas and the residual refrigerant oil in the
pipes before heating them.

iv
[5] Wiring Work
To reduce the risk of pipe damage, refriger-
ant leakage, and oxygen deprivation, use
pipes that meet the pipe thickness specifi-
cations, which vary by the type of refriger-
ant used, pipe diameter, and pipe material.
To reduce the risk of pipe burst or explo-
sion, evacuate therefrigerant circuit using a
vacuum pump, and do not purge the system
with refrigerant.
To reduce the risk of explosion and deterio-
ration of refrigerant oil caused by chloride,
do not use oxygen, flammable gas, or refrig-
erant that contains chloride as a pressuriz-
ing gas.
To prevent explosion, do not heat the unit
with refrigerant gas in the refrigerant circuit.
To reduce the risk of oxygen deprivation
and gas poisoning, check for gas leakage
and keep fire sources away.
Insulate pipe connections after completing
the air tightness test. Performing an air
tightness test with the pipe being insulated
may lead to failure to detect refrigerant leak-
age and cause oxygen deprivation.
To reduce the risk of pipe damage and re-
sultant refrigerant leakage and oxygen de-
privation, keep the field-installed pipes out
of contact with the edges of components.
To reduce the risk of pipe bursting and ex-
plosion due to abnormal pressure rise, do
not allow any substances other than R410A
(such as air) to enter the refrigerant circuit.
To keep the ceiling and floor from getting
wet due to condensation, properly insulate
the pipes.
Wiring Work
To reduce the risk of wire breakage, over-
heating, smoke, and fire, keep undue force
from being applied to the wires.
To reduce the risk of wire breakage, over-
heating, smoke, or fire, properly secure the
cables in place and provide adequate slack
in the cables so as not to stress the termi-
nals.
All electric work must be performed by a
qualified electrician according to the local
regulations, standards,and the instructions
detailed in the Installation Manual. Capacity
shortage to the power supply circuit or im-
proper installation may result in malfunc-
tion, electric shock, smoke, or fire.
To reduce the risk of electric shock, smoke,
or fire, install an inverter circuit breaker on
the power supply to each unit.
Use properly rated breakers and fuses (in-
vertercircuit breaker, local switch <switch +
fuse>, no-fuse breaker). The use of a break-
er with a breaking capacity greater than the
specified capacity may cause electric
shock, malfunctions, smoke, or fire.
To reduce the risk of current leakage, over-
heating, smoke, or fire, use properly rated
cables with adequate current carrying ca-
pacity.
Proper grounding must be provided by a li-
censed electrician.
Do not connect the grounding wire to a gas
pipe, water pipe, lightning rod, or telephone
wire. Improper grounding may result in
electric shock, smoke, fire, or malfunction
due to electrical noise interference.
To reduce the risk of current leakage, wire
breakage, smoke, or fire, keep the wiring
out of contact with the refrigerant pipes and
other parts, especially sharp edges.

v
[6] Relocation and Repairs
[7] Additional Precautions
Relocation and Repairs
To reduce the risk of refrigerant leakage,
water leakage, injury, electric shock, and
fire, units should only be moved or repaired
by your dealer or qualified personnel.
To reduce the risk of wire shorting, electric
leak, electric shock, smoke, or fire, do not
perform maintenance work in the rain.
To reduce the risk of injury, electric shock,
and fire, properly reinstall all removed com-
ponents after completing repair work.
To reduce the risk of wire shorting, electric
shock, malfunctions, or fire, keep circuit
boards dust free, and do not touch them
with your hands or tools.
To reduce the risk of refrigerant and water
leakage, check the pipe supports and insu-
lation for damage during inspection or re-
pair, and replace or repair the ones that are
found to be deteriorated.
Additional Precautions
To avoid damage to the unit, use appropri-
ate tools to install, inspect, or repair the
unit.
To reduce the risk or malfunction, turn on
the power at least 12 hours before starting
operation, and leave the power turned on
throughout the operating season.
Recover all refrigerant in the units, and dis-
pose of it properly according to any applica-
ble laws and regulations.
Provide a maintenance access to allow for
the inspection of pipes above the ceiling or
the buried pipes.
Take appropriate measures against electri-
calnoise interferencewheninstalling theair
conditioners in hospitals or facilities with
radio communication capabilities. Inverter,
high-frequency medical, or wireless com-
munication equipment as well as power
generators may cause the air conditioning
system to malfunction. Air conditioning
system may also adversely affect the opera-
tion of these types of equipment by creating
electrical noise.
To reduce the risk of damage to the unit,
leave the valves on the unit closed until re-
frigerant charging is completed.
Place a wet towel on the refrigerant service
valve before brazing the pipes to keep its
temperature from rising above 120ºC and
damaging the surrounding equipment.
Direct the blazing torch flame away from the
adjacent cables and sheet metal to keep
them from being overheated and damaged.
Prepare tools for exclusive use with R410A.
Do not use the following tools if they have
been used with the conventional refrigerant
(R22): gauge manifold, charging hose, re-
frigerant leak detector, check valve, refrig-
erant charge spout, vacuum gauge, and
refrigerant recovery equipment. R410A
does not contain chloride, so leak detectors
for use with older types of refrigerants will
not detect an R410A leak. Infiltration of the
residual refrigerant, refrigerant oil, or water
on these tools may cause the refrigerant oil
in the new system to deteriorate or damage
the compressor.
To reduce the risk of the vacuum pump oil
backflowing into the refrigerant cycle and
causing the refrigerant oil to deteriorate,
use a vacuum pump with a check valve.
Have a set of tools for exclusive use with
R410A. Consult your nearest Mitsubishi
Electric Dealer.
Keep dust, dirt, and water off charging hose
and flare tool. Infiltration of dust, dirt, or wa-
ter into the refrigerant circuit may cause the
refrigerant oil to deteriorate or damage the
compressor.

vi
Use refrigerant piping and couplings that
meet the applicable standards. For refriger-
ant pipes, use pipes made of phosphorus
deoxidized copper. Keep the inner and out-
er surfaces of pipes and couplings clean
and free of such contaminants as sulfur, ox-
ides, dust, dirt, shaving particles, oil, and
moisture. Failure to follow these directions
may result in the deterioration of refrigerant
oil or compressor damage.
Store the piping materials indoors, and
keep both ends of the pipes sealed until im-
mediately before brazing. Keep elbows and
other joints in plastic bags. Infiltration of
dust, dirt, or water into the refrigerant cir-
cuit may cause the refrigerant oil to deterio-
rate or damage the compressor.
Apply ester oil, ether oil, or a small amount
of alkyl benzene to flares and flanges. The
use and accidental infiltration of mineral oil
into the system may cause the refrigerant
oil to deteriorate or damage the compres-
sor.
To reduce the risk of oxidized film from en-
tering the refrigerant pipe and causing the
refrigerant oil to deteriorate or damaging
thecompressor,brazepipesundernitrogen
purge.
Do not use the existing refrigerant piping. A
large amount of chloride that is contained in
the residual refrigerant and refrigerant oil in
the existing piping may cause the refriger-
ant oil in the new unit to deteriorate or dam-
age the compressor.
Charge refrigerant in the liquid state. If re-
frigerant is charged in the gas phase, the
composition of the refrigerant in the cylin-
der will change, compromising the unit's
performance.
Do not use a charging cylinder. The use of a
charging cylinder will change the composi-
tion of the refrigerant, compromising the
unit's performance.
Charge the system with an appropriate
amount of refrigerant in the liquid phase.
Refer to the relevant sections in the manu-
als to calculate the appropriate amount of
refrigerant to be charged. Refrigerant over-
charge or undercharge may result in perfor-
mance drop or abnormal stop of operation.
To reduce the risk of power capacity short-
age, always use a dedicated power supply
circuit.
To reduce the risk of both the breaker on the
product side and the upstream breaker from
tripping and causing problems, split the
power supply system or provide protection
coordination between the earth leakage
breaker and no-fuse breaker.
Have a backup system, if failure of the unit
has a potential for causing significant prob-
lems or damages.

CONTENTS
HWE18240_GB
Chapter 1 Check Before Servicing
1-1 Preparation for Piping Work..................................................................................................................1
1-2 Handling and Characteristics of Piping Materials, Refrigerant, and Refrigerant Oil.......................3
1-3 Working with Refrigerant Piping...........................................................................................................7
1-4 Precautions for Wiring.........................................................................................................................11
1-5 Cautionary notes on installation environment and maintenance....................................................13
Chapter 2 Restrictions
2-1 System Configurations..........................................................................................................................1
2-2 Types and Maximum Allowable Length of Cables..............................................................................2
2-3 Switch Settings.......................................................................................................................................3
2-4 M-NET Address Settings .......................................................................................................................4
2-5 Demand Control Overview ....................................................................................................................9
2-6 System Connection Example..............................................................................................................11
2-7 Example System with an MA Remote Controller ..............................................................................12
2-8 Example System with an ME Remote Controller...............................................................................22
2-9 Example System with an MA and an ME Remote Controller............................................................24
2-10 Restrictions on Refrigerant Pipes ......................................................................................................26
Chapter 3 Major Components, Their Functions and Refrigerant Circuits
3-1 External Appearance and Refrigerant Circuit Components of Outdoor Unit ...................................1
3-2 Outdoor Unit Refrigerant Circuit Diagrams.........................................................................................3
3-3 Functions of the Major Components of Outdoor Unit ........................................................................4
3-4 Functions of the Major Components of Indoor Unit ...........................................................................7
Chapter 4 Electrical Components and Wiring Diagrams
4-1 Outdoor Unit Circuit Board Arrangement............................................................................................1
4-2 Outdoor Unit Circuit Board Components ............................................................................................4
4-3 Outdoor Unit Electrical Wiring Diagrams...........................................................................................14
4-4 Transmission Booster Electrical Wiring Diagrams...........................................................................16
Chapter 5 Control
5-1 Dipswitch Functions and Factory Settings..........................................................................................1
5-2 Outdoor Unit Control .............................................................................................................................9
Chapter 6 Test Run
6-1 Read before Test Run ............................................................................................................................1
6-2 Operation Characteristics and Refrigerant Charge ............................................................................2
6-3 Evaluating and Adjusting Refrigerant Charge.....................................................................................2
6-4 The Following Symptoms Are Normal .................................................................................................6
Chapter 7 Troubleshooting Using Error Codes
7-1 Error Code and Preliminary Error Code Lists .....................................................................................1
7-2 Error Code Definitions and Solutions: Codes [0 - 999].......................................................................6
7-3 Error Code Definitions and Solutions: Codes [1000 - 1999]...............................................................8
7-4 Error Code Definitions and Solutions: Codes [2000 - 2999].............................................................12
7-5 Error Code Definitions and Solutions: Codes [3000 - 3999].............................................................18
7-6 Error Code Definitions and Solutions: Codes [4000 - 4999].............................................................21
7-7 Error Code Definitions and Solutions: Codes [5000 - 5999].............................................................38
7-8 Error Code Definitions and Solutions: Codes [6000 - 6999].............................................................45
7-9 Error Code Definitions and Solutions: Codes [7000 - 7999].............................................................66

CONTENTS
HWE18240_GB
Chapter 8 Troubleshooting Based on Observed Symptoms
8-1 MA Remote Controller Problems..........................................................................................................1
8-2 ME remote Controller Problems ...........................................................................................................5
8-3 Refrigerant Control Problems.............................................................................................................10
8-4 Checking Transmission Waveform and for Electrical Noise Interference......................................15
8-5 Pressure Sensor Circuit Configuration and Troubleshooting Pressure Sensor Problems ..........18
8-6 Troubleshooting Solenoid Valve Problems.......................................................................................22
8-7 Troubleshooting Outdoor Unit Fan Problems...................................................................................24
8-8 Troubleshooting LEV Problems..........................................................................................................25
8-9 Troubleshooting Inverter Problems ...................................................................................................31
8-10 Control Circuit ......................................................................................................................................44
8-11 Measures for Refrigerant Leakage .....................................................................................................50
8-12 Parts Replacement Instructions .........................................................................................................52
8-13 Troubleshooting Problems Using the LED Status Indicators on the Outdoor Unit.......................79
Chapter 9 USB Function
9-1 Service Overview....................................................................................................................................1
9-2 Operation Data Collection and Storage Functions .............................................................................4
9-3 Software Rewrite Function on the USB................................................................................................8
9-4 Maintenance LED Display and Troubleshooting...............................................................................10
Chapter 10 LED Status Indicators on the Outdoor Unit Circuit Board
10-1 LED Status Indicators............................................................................................................................1
10-2 LED Status Indicators Table..................................................................................................................4

HWE18240_GB
Chapter 1 Check Before Servicing
1-1 Preparation for Piping Work ................................................................................................................ 1
1-1-1 Read before Servicing ............................................................................................................................ 1
1-1-2 Tool Preparation ..................................................................................................................................... 2
1-2 Handling and Characteristics of Piping Materials, Refrigerant, and Refrigerant Oil...................... 3
1-2-1 Piping Materials ...................................................................................................................................... 3
1-2-2 Storage of Piping Materials..................................................................................................................... 4
1-2-3 Pipe Processing...................................................................................................................................... 4
1-2-4 Characteristics of the New and Conventional Refrigerants .................................................................... 5
1-2-5 Refrigerant Oil......................................................................................................................................... 6
1-3 Working with Refrigerant Piping ......................................................................................................... 7
1-3-1 Pipe Brazing............................................................................................................................................ 7
1-3-2 Air Tightness Test................................................................................................................................... 8
1-3-3 Vacuum Drying ....................................................................................................................................... 9
1-3-4 Refrigerant Charging............................................................................................................................. 10
1-4 Precautions for Wiring ....................................................................................................................... 11
1-5 Cautionary notes on installation environment and maintenance .................................................. 13

HWE18240_GB

[1-1 Preparation for Piping Work ]
HWE18240_GB chapter 1 - 1
1 Check Before Servicing
1 Check Before Servicing
1-1 Preparation for Piping Work
1-1-1 Read before Servicing
1. Check the type of refrigerant used in the system to be serviced.
Refrigerant Type
Multi air conditioner for building application CITY MULTI:R410A
2. Check the symptoms exhibited by the unit to be serviced.
Refer to this service handbook for symptoms relating to the refrigerant cycle.
3. Thoroughly read the safety precautions at the beginning of this manual.
4. Preparing necessary tools: Prepare a set of tools to be used exclusively with each type of re-
frigerant.
For information about the correct use of tools, refer to the following page(s). [1-1-2 Tool Preparation]
5. Verification of the connecting pipes: Verify the type of refrigerant used for the unit to be moved
or replaced.
Use refrigerant pipes made of phosphorus deoxidized copper. Keep the inner and outer surfaces of the pipes clean and free
of such contaminants as sulfur, oxides, dust, dirt, shaving particles, oil, and water.
These types of contaminants inside the refrigerant pipes may cause the refrigerant oil to deteriorate.
6. If there is a leak of gaseous refrigerant and the remaining refrigerant is exposed to an open
flame, a poisonous gas hydrofluoric acid may form. Keep workplace well ventilated.
7. Specifications and system requirements may differ for products manufactured at different
times. Refer to the relevant chapters for specification details. Production periods can be found
from the serial number as follows.
Note
Install new pipes immediately after removing old ones to keep moisture out of the refrigerant circuit.
The use of refrigerant that contains chloride, such as R22, will cause the refrigerating machine oil to deteriorate.
8XP ...
1~9: Jan to Sept.
X~Z: Oct to Dec.
8: April 2018 to March 2019
(Production month)
(Production year)

[1-1 Preparation for Piping Work ]
2 - chapter 1 HWE18240_GB
1 Check Before Servicing
1-1-2 Tool Preparation
Prepare the following tools and materials necessary for installing and servicing the unit.
Tools for use with R410A (Adaptability of tools that are for use with R22 or R407C)
1. To be used exclusively with R410A (not to be used if used with R22 or R407C)
2. Tools and materials that may be used with R410A with some restrictions
3. Tools and materials that are used with R22 or R407C that may also be used with R410A
4. Tools and materials that must not be used with R410A
Tools for R410A must be handled with special care to keep moisture and dust from infiltrating the cycle.
Tools/Materials Use Notes
Gauge Manifold Evacuation and refrigerant charging Higher than 5.09MPa[738psi] on the
high-pressure side
Charging Hose Evacuation and refrigerant charging The hose diameter is larger than the
conventional model.
Refrigerant Recovery Cylinder Refrigerant recovery
Refrigerant Cylinder Refrigerant charging The refrigerant type is indicated. The
cylinder is pink.
Charging Port on the RefrigerantCylinder Refrigerant charging The charge port diameter is larger
than that of the current port.
Flare Nut Connection of the unit with the pipes Use Type-2 Flare nuts.
Tools/Materials Use Notes
Gas Leak Detector Gas leak detection The ones for use with HFC refrigerant
may be used.
Vacuum Pump Vacuum drying May be used if a check valve adapter
is attached.
Flare Tool Flare processing Flare processing dimensions for the
piping in the system using the new re-
frigerant differ from those of R22. Re-
fer to the following page(s). [1-2-1
Piping Materials]
Refrigerant Recovery Equipment Refrigerant recovery May be used if compatible with
R410A.
Tools/Materials Use Notes
Vacuum Pump with a Check Valve Vacuum drying
Bender Bending pipes
Torque Wrench Tightening flare nuts Only the flare processing dimensions
for pipes that have a diameter of
ø12.7 (1/2") and ø15.88 (5/8") have
been changed.
Pipe Cutter Cutting pipes
Welder and Nitrogen Cylinder Welding pipes
Refrigerant Charging Meter Refrigerant charging
Vacuum Gauge Vacuum level check
Tools/Materials Use Notes
Charging Cylinder Refrigerant charging Prohibited to use

[1-2 Handling and Characteristics of Piping Materials, Refrigerant, and Refrigerant Oil ]
HWE18240_GB chapter 1 - 3
1 Check Before Servicing
1-2 Handling and Characteristics of Piping Materials,
Refrigerant, and Refrigerant Oil
1-2-1 Piping Materials
1. Copper pipe materials
The distinction between Annealed and Drawn is made based on the strength of the pipes themselves.
Annealed can easily be bent with hands.
Drawn are considerably stronger than Annealed at the same thickness.
2. Types of copper pipes
3. Piping materials/Radial thickness
Select piping materials that meet the requirements set forth in ASTM B280.
4. Thickness and refrigerant type indicated on the piping materials
Ask the pipe manufacturer for the symbols indicated on the piping material for new refrigerant (R410A).
5. Flare processing
Select piping materials that meet the requirements set forth in ASTM.
6. Flare nut
Select piping materials that meet the requirements set forth in ASTM.
Annealed Soft copper pipes (annealed copper pipes). They can easily be bent with hands.
Drawn Hard copper pipes (straight pipes). They are stronger than the Annealed at the same
radial thickness.
Maximum working pressure Refrigerant type
3.45 MPa [500psi] R22, R407C etc.
4.30 MPa [624psi] R410A etc.
Do not use the existing piping!

[1-2 Handling and Characteristics of Piping Materials, Refrigerant, and Refrigerant Oil ]
4 - chapter 1 HWE18240_GB
1 Check Before Servicing
1-2-2 Storage of Piping Materials
1. Storage location
Store the pipes to be used indoors. (Warehouse at site or owner's warehouse)
If they are left outdoors, dust, dirt, or moisture may infiltrate and contaminate the pipe.
2. Sealing the pipe ends
Both ends of the pipes should be sealed until just before brazing.
Keep elbow pipes and T-joints in plastic bags.
The new refrigerator oil is 10 times as hygroscopic as the conventional refrigerating machine oil (such as Suniso) and, if not
handled with care, could easily introduce moisture into the system. Keep moisture out of the pipes, for it will cause the oil to
deteriorate and cause a compressor failure.
1-2-3 Pipe Processing
Use a small amount of ester oil, ether oil, or alkylbenzene to coat flares and flanges.
When processing the severed ends of the pipes, keep the shaving dust out of the pipes to prevent malfunction of the refrigerant
circuit.
Use a minimum amount of oil.
Use only ester oil, ether oil, and alkylbenzene.

[1-2 Handling and Characteristics of Piping Materials, Refrigerant, and Refrigerant Oil ]
HWE18240_GB chapter 1 - 5
1 Check Before Servicing
1-2-4 Characteristics of the New and Conventional Refrigerants
1. Chemical property
As with R22, the new refrigerant (R410A) is low in toxicity and chemically stable nonflammable refrigerant.
However, because the specific gravity of vapor refrigerant is greater than that of air, leaked refrigerant in a closed room will
accumulate at the bottom of the room and may cause hypoxia.
If exposed to an open flame, refrigerant will generate poisonous gases. Do not perform installation or service work in a con-
fined area.
*1 When CFC11 is used as a reference
*2 When CO2is used as a reference
2. Refrigerant composition
R410A is a pseudo-azeotropic HFC blend and can almost be handled the same way as a single refrigerant, such as R22. To
be safe, however, draw out the refrigerant from the cylinder in the liquid phase. If the refrigerant in the gaseous phase is drawn
out, the composition of the remaining refrigerant will change and become unsuitable for use.
If the refrigerant leaks out, it may be replenished.
3. Pressure characteristics
The pressure in the system using R410A is 1.6 times as great as that in the system using R22.
New Refrigerant (HFC type) Conventional Refriger-
ant (HCFC type)
R410A R407C R22
R32/R125 R32/R125/R134a R22
Composition (wt%) (50/50) (23/25/52) (100)
Type of Refrigerant Pseudo-azeotropic
Refrigerant Non-azeotropic Refrigerant Single Refrigerant
Chloride Not included Not included Included
Safety Class A1/A1 A1/A1 A1
Molecular Weight 72.6 86.2 86.5
Boiling Point (°C/°F) -51.4/-60.5 -43.6/-46.4 -40.8/-41.4
Steam Pressure
(25°C,MPa/77°F,psi) (gauge) 1.557/226 0.9177/133 0.94/136
Saturated Steam Density
(25°C,kg/m3/77°F,psi) 64.0 42.5 44.4
Flammability Nonflammable Nonflammable Nonflammable
Ozone Depletion Coefficient (ODP)*1 0 0 0.055
Global Warming Coefficient (GWP)*2 2088 1774 1810
Refrigerant Charging Method Refrigerantchargingin
the liquid state Refrigerantchargingin the liquid state Refrigerantchargingin the gaseous state
Replenishment of Refrigerant after a Refrigerant
Leak Available Available Available
Temperature (°C/°F)
Pressure (gauge)
R410A R407C R22
MPa/psi MPa/psi MPa/psi
-20/-4 0.30/44 0.18/26 0.14/20
0/32 0.70/102 0.47/68 0.40/58
20/68 1.34/194 0.94/136 0.81/117
40/104 2.31/335 1.44/209 1.44/209
60/140 3.73/541 2.44/354 2.33/338
65/149 4.17/605 2.75/399 2.60/377

[1-2 Handling and Characteristics of Piping Materials, Refrigerant, and Refrigerant Oil ]
6 - chapter 1 HWE18240_GB
1 Check Before Servicing
1-2-5 Refrigerant Oil
1. Refrigerating machine oil in the HFC refrigerant system
HFC type refrigerants use a refrigerating machine oil different from that used in the R22 system.
Note that the ester oil used in the system has properties that are different from commercially available ester oil.
This unit requires refrigerant oil that is compatible with low temperature refrigerant.
2. Effects of contaminants*1
Refrigerating machine oil used in the HFC system must be handled with special care to keep contaminants out.
The table below shows the effect of contaminants in the refrigerating machine oil on the refrigeration cycle.
3. The effects of contaminants in the refrigerating machine oil on the refrigeration cycle.
Refrigerant Refrigerating machine oil
R22 Mineral oil
R407C Ester oil
R410A Ester oil
*1. Contaminants is defined as moisture, air, processing oil, dust/dirt, wrong types of refrigerant, and refrigerating machine oil.
Cause Symptoms Effects on the refrigerant cycle
Water infiltration Frozen expansion valve
and capillary tubes Clogged expansion valve and capillary tubes Poor cooling performance
Compressor overheat
Motor insulation failure
Burnt motor
Coppering of the orbiting scroll
Lock
Burn-in on the orbiting scroll
Hydrolysis Sludge formation and ad-
hesion
Acid generation
Oxidization
Oil degradation
Air infiltration Oxidization
Infiltration of
contaminants
Dust, dirt
Adhesion to expansion valve and capillary
tubes Clogged expansion valve, capillary tubes, and drier
Poor cooling performance
Compressor overheat
Infiltration of contaminants into the com-
pressor Burn-in on the orbiting scroll
Mineral oil
etc.
Sludge formation and adhesion Clogged expansion valve and capillary tubes
Poor cooling performance
Compressor overheat
Oil degradation Burn-in on the orbiting scroll

[1-3 Working with Refrigerant Piping ]
HWE18240_GB chapter 1 - 7
1 Check Before Servicing
1-3 Working with Refrigerant Piping
1-3-1 Pipe Brazing
No changes have been made in the brazing procedures. Perform brazing with special care to keep foreign objects (such as oxide
scale, water, and dust) out of the refrigerant system.
Example: Inside the brazed connection
1. Items to be strictly observed
Do not conduct refrigerant piping work outdoors if raining.
Use inert gas during brazing.
Use a brazing material (BCuP-3) that requires no flux when brazing between copper pipes or between a copper pipe and
copper coupling.
If installed refrigerant pipes are not immediately connected to the equipment, then braze and seal both ends.
2. Reasons
The new refrigerating machine oil is 10 times as hygroscopic as the conventional oil and is more likely to cause unit failure if
water infiltrates into the system.
Flux generally contains chloride. Residual flux in the refrigerant circuit will cause sludge to form.
3. Notes
Do not use commercially available antioxidants because they may cause the pipes to corrode or refrigerating machine oil to
deteriorate.
Use of no inert gas during brazing Use of inert gas during brazing

[1-3 Working with Refrigerant Piping ]
8 - chapter 1 HWE18240_GB
1 Check Before Servicing
1-3-2 Air Tightness Test
No changes have been made in the detection method. Note that a refrigerant leak detector for R22 will not detect an R410A leak.
1. Items to be strictly observed
Pressurize the equipment with nitrogen up to the design pressure (4.15MPa[601psi]), and then judge the equipment's air tight-
ness, taking temperature variations into account.
Refrigerant R410A must be charged in its liquid state (vs. gaseous state).
2. Reasons
Oxygen, if used for an air tightness test, poses a risk of explosion. (Only use nitrogen to check air tightness.)
Refrigerant R410A must be charged in its liquid state. If gaseous refrigerant in the cylinder is drawn out first, the composition
of the remaining refrigerant in the cylinder will change and become unsuitable for use.
3. Notes
Procure a leak detector that is specifically designed to detect an HFC leak. A leak detector for R22 will not detect an
HFC(R410A) leak.
Halide torch R22 leakage detector

[1-3 Working with Refrigerant Piping ]
HWE18240_GB chapter 1 - 9
1 Check Before Servicing
1-3-3 Vacuum Drying
1. Vacuum pump with a reverse-flow check valve (Photo1)
To prevent the vacuum pump oil from flowing into the refrigerant circuit during power OFF or power failure, use a vacuum
pump with a reverse-flow check valve.
A reverse-flow check valve may also be added to the vacuum pump currently in use.
2. Standard of vacuum degree (Photo 2)
Use a vacuum pump that attains 0.5Torr(65Pa) or lower degree of vacuum after 5 minutes of operation, and connect it directly
to the vacuum gauge. Use a pump well-maintained with an appropriate lubricant. A poorly maintained vacuum pump may not
be able to attain the desired degree of vacuum.
3. Required precision of vacuum gauge
Use a vacuum gauge that registers a vacuum degree of 5Torr(650Pa) and measures at intervals of 1Torr(130Pa). (A recom-
mended vacuum gauge is shown in Photo2.)
Do not use a commonly used gauge manifold because it cannot register a vacuum degree of 5Torr(650Pa).
4. Evacuation time
After the degree of vacuum has reached 5Torr(650Pa), evacuate for an additional 1 hour. (A thorough vacuum drying re-
moves moisture in the pipes.)
Verify that the vacuum degree has not risen by more than 1Torr(130Pa) 1hour after evacuation. A rise by less than
1Torr(130Pa) is acceptable.
If the vacuum is lost by more than 1Torr(130Pa), conduct evacuation, following the instructions in section 6. Special vacuum
drying.
5. Procedures for stopping vacuum pump
To prevent the reverse flow of vacuum pump oil, open the relief valve on the vacuum pump side, or draw in air by loosening
the charge hose, and then stop the operation.
The same procedures should be followed when stopping a vacuum pump with a reverse-flow check valve.
6. Special vacuum drying
When 5Torr(650Pa) or lower degree of vacuum cannot be attained after 3 hours of evacuation, it is likely that water has pen-
etrated the system or that there is a leak.
If water infiltrates the system, break the vacuum with nitrogen. Pressurize the system with nitrogen gas to
0.5kgf/cm2G(0.05MPa) and evacuate again. Repeat this cycle of pressurizing and evacuation either until the degree of vac-
uum below 5Torr(650Pa) is attained or until the pressure stops rising.
Only use nitrogen gas for vacuum breaking. (The use of oxygen may result in an explosion.)
7. Triple Evacuation
The method below can also be used to evacuate the system.
Evacuate the system to 4,000 microns from both service valves. System manifold gauges must not be used to measure vac-
uum. A micron gauge must be used at all times. Break the vacuum with Nitrogen (N2) into the discharge service valve to 0
PSIG.
Evacuate the system to 1,500 microns from the suction service valve. Break the vacuum with Nitrogen (N2) into the discharge
service valve to 0 PSIG.
Evacuate the system to 500 microns. System must hold the vacuum at 500 microns for a minimum of 1 hour.
Conduct a rise test for a minimum of 30 minutes
(Photo1) 15010H (Photo2) 14010
Recommended vacuum gauge:
ROBINAIR 14010 Thermistor Vacuum Gauge