Mitsubishi Electric CAHV-R450YA-HPB User manual

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Safety Precautions
• Thoroughly read the following safety precautions prior to use.
• Observe these precautions carefully to ensure safety.
WARNING
WARNING
Indicates a risk of death or serious injury
CAUTION
Indicates a risk of injury or structural damage
IMPORTANT
Indicates a risk of damage to the unit or other components in the system
General
All electric work must be performed by personnel certified by Mitsubishi Electric.
Do not use refrigerant other than the type indicated 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.
• MITSUBISHI ELECTRIC CORPORATION cannot be held
responsible for malfunctions or accidents 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
frequently.
These substances can compromise the performance of the
unit or cause certain components of the unit to corrode,
which can result in refrigerant leakage, water leakage, injury,
electric shock, malfunctions, smoke, or fire.
Do not try to defeat the safety features of the unit or
make unauthorized setting changes.
Forcing the unit to operate the unit by defeating the safety
features of the devices such as the pressure switch or the
temperature switch, making unauthorized changes to the
switch settings, or using accessories other than the ones
recommended by Mitsubishi Electric may result in smoke,
fire, or explosion.
To reduce the risk of fire or explosion, do not use volatile or
flammable substances as a heat carrier.
To reduce the risk of burns or electric shock, do not touch
exposed pipes and wires.
To reduce the risk of shorting, current leakage, electric
shock, malfunctions, smoke, or fire, do not splash water on
electric parts.
To reduce the risk of electric shock, malfunctions, smoke or
fire, do not operate the switches/buttons or touch other
electrical parts with wet hands.
To reduce the risk of electric shock and injury from the fan or
other rotating parts, stop the operation and turn off the main
power before cleaning, maintaining, or inspecting the unit.
To reduce the risk of burns or frost bites, do not touch the
refrigerant pipes or refrigerant circuit components with bare
hands during and immediately after operation.
Before cleaning the unit, switch off the power.
(Unplug the unit, if it is plugged in.)
To reduce the risk of injury, keep children away while
installing, inspecting, or repairing the unit.
Children should be supervised to ensure that they do not play
with the appliance.
This appliance is not intended for use by persons (including
children) with reduced physical, sensory or mental
capabilities, or lack of experience and knowledge, unless
they have been given supervision or instruction concerning
use of the appliance by a person responsible for their safety.
Keep the space well ventilated. Refrigerant can displace
air and cause oxygen starvation.
If leaked refrigerant comes in contact with a heat source,
toxic gas may be generated.
Always replace a fuse with one with the correct current
rating.
The use of improperly rated fuses or a substitution of fuses
with steel or copper wire may result in fire or explosion.
If any abnormality (e.g., burning smell) is noticed, stop
the operation, turn off the power switch, and consult
your dealer.
Continuing the operation may result in electric shock,
malfunctions, or fire.
Properly install all required covers and panels on the
terminal box and control box to keep moisture and dust
out.
Dust accumulation and water may result in electric shock,
smoke, or fire.
Consult an authorized agency for the proper disposal of
the unit
Refrigerant oil and refrigerant that may be left in the unit pose
a risk of fire, explosion, or environmental pollution.
Do not use means to accelerate the defrosting process
or to clean, other than those recommended by the
manufacturer.
The appliance shall be stored in a room without
continuously operating ignition sources (for example:
open flames, an operating gas appliance or an operating
electric heater.)
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CAUTION
WARNING
Do not pierce or burn. Be aware that refrigerants may not contain an odour.
To reduce the risk of fire or explosion, do not place
flammable materials or use flammable sprays around the
unit.
Do not operate the unit without panels and safety guards
properly installed.
To reduce the risk of injury, do not sit, stand, or place objects
on the unit.
Do not connect the makeup water pipe directly to the
potable water pipe. Use a cistern tank between them.
Connecting these pipes directly may cause the water in the
unit to migrate into the potable water and cause health
problems.
To reduce the risk of adverse effects on plants and animals,
do not place them where they are directly exposed to
discharge air from the unit.
Do not install the unit on or over things that are
vulnerable to water damage.
Condensation may drip from the unit.
The model of heat pump unit described in this manual is not
intended for use to preserve food, animals, plants, precision
instruments, or art work.
To reduce the risk of injury, do not touch the heat exchanger
fins or sharp edges of components with bare hands.
Do not place a container filled with water on the unit.
If water spills on the unit, it may result in shorting, current
leakage, electric shock, malfunction, smoke, or fire.
Always wear protective gears when touching electrical
components on the unit.
Several minutes after the power is switched off, residual
voltage may still cause electric shock.
To reduce the risk of injury, do not insert fingers or foreign
objects into air inlet/outlet grills.
To reduce the risk of injury, wear protective gear when
working on the unit.
Do not release refrigerant into the atmosphere. Collect
and reuse the refrigerant, or have it properly disposed of
by an authorized agency.
Refrigerant poses environmental hazards if released into the
air.
To prevent environmental pollution, dispose of brine in
the unit and cleaning solutions according to the local
regulations.
It is punishable by law not to dispose of them according to the
applicable laws.
The water heated by the heat pump is not suitable for
use as drinking water or for cooking.
It may cause health problems or degrade food.
In areas where temperature drops to freezing during the
periods of non-use, blow the water out of the pipes or fill
the pipes with anti-freeze solution.
Not doing so may cause the water to freeze, resulting in burst
pipes and damage to the unit or the furnishings.
In areas where temperature drops to freezing, use an anti-
freeze circuit and leave the main power turned on to prevent
the water in the water circuit from freezing and damaging the
unit or causing water leakage and resultant damage to the
furnishings.
Use clean tap water.
The use of acidic or alkaline water or water high in chlorine
may corrode the unit or the pipes, causing water leakage and
resultant damage to the furnishings.
In areas where temperature can drop low enough to
cause the water in the pipes to freeze, operate the unit
often enough to prevent the water from freezing.
Frozen water in the water circuit may cause the water to
freeze, resulting in burst pipes and damage to the unit or the
furnishings.
Periodically inspect and clean the water circuit.
Dirty water circuit may compromise the unit’s performance or
corrodes the unit or cause water leakage and resultant
damage to the furnishings.
Ensure that the flow rate of the feed-water is within the
permitted range.
If the flow rate exceeds the permitted range, the unit may
become damaged due to corrosion. Furniture may become
wet due to water leaks.
Do not install the unit in an indoor or semi-underground
space.
• If the refrigerant leaks, a fire may result.
• The unit must be stored where leaking refrigerant will not
accumulate.
Transportation
Lift the unit by placing the slings at designated
locations. Support the outdoor unit securely at four
points to keep it from slipping and sliding.
If the unit is not properly supported, it may fall and cause
personal injury.
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CAUTION
WARNING
CAUTION
WARNING
CAUTION
To reduce the risk of injury, do not carry the product by the
PP bands that are used on some packages.
Observe the restrictions on the maximum weight that a
person can lift, which is specified in local regulations.
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 explosion.
Properly dispose of the packing materials.
Plastic bags pose suffocation hazard to children.
The unit should be installed only by personnel certified
by Mitsubishi Electric according to the instructions
detailed in the Installation/Operation Manual.
Improper installation may result in refrigerant leakage, water
leakage, injury, electric shock, or fire.
Periodically check the installation base for damage.
If the unit is left on a damaged base, it may fall and cause
injury.
Remove packing materials from the unit before operating
the unit. Note that some accessories may be taped to the
unit. Properly install all accessories that are required.
Failing to remove the packing materials or failing to install
required accessories may result in refrigerant leakage,
oxygen starvation, smoke, or fire.
Consult your dealer and take appropriate measures to
safeguard against refrigerant leakage and resultant oxygen
starvation. An installation of a refrigerant gas detector is
recommended.
Any additional parts must be installed by qualified personnel.
Only use the parts specified by Mitsubishi Electric.
Take appropriate safety measures against wind gusts and
earthquakes to prevent the unit from toppling over and
causing injury.
Be sure to install the unit horizontally, using a level.
If the unit is installed at an angle, it may fall and cause injury
or cause water leakage.
The unit should be installed on a surface that is strong
enough to support its weight.
As an anti-freeze, use ethylene glycol or propylene
glycol diluted to the specified concentration.
The use of other types of anti-freeze solution may cause
corrosion and resultant water leakage. The use of flammable
anti-freeze may cause fire or explosion.
Do not install the unit on or over things that are
vulnerable to water damage.
When the indoor humidity exceeds 80% or if the drain water
outlet becomes clogged, condensation may drip from the
indoor unit onto the ceiling or floor.
All drainage work should be performed by the dealer or
qualified personnel according to the instructions
detailed in the Installation Manual.
Improper drainage work may cause rain water or drain water
to enter the buildings and damage the furnishings.
Pipe installation
To prevent explosion, do not heat the unit with refrigerant gas
in the refrigerant circuit. Check for refrigerant leakage at the completion of
installation.
If leaked refrigerant comes in contact with a heat source,
toxic gas may be generated.
Check that no substance other than the specified
refrigerant (R454C) is present in the refrigerant circuit.
Infiltration of other substances may cause the pressure to
rise abnormally high and cause the pipes to explode.
To keep the ceiling and floor from getting wet due to
condensation, properly insulate the pipes.
Piping work should be performed by the dealer or
qualified personnel according to the instructions
detailed in the Installation Manual.
Improper piping work may cause water leakage and damage
the furnishings.
To keep the ceiling and floor from getting wet due to
condensation, properly insulate the pipes.
Do not open the control box cover while charging
refrigerant.
• If the refrigerant leaks, a fire may result.
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WARNING
CAUTION
WARNING
CAUTION
Electrical wiring
To reduce the risk of wire breakage, overheating, smoke, and
fire, keep undue force from being applied to the wires.
Properly secure the cables in place and provide
adequate slack in the cables so as not to stress the
terminals.
Improperly connected cables may break, overheat, and
cause smoke or fire.
To reduce the risk of injury or electric shock, switch off the
main power before performing electrical work.
All electric work must be performed by a qualified
personnel according to the local regulations, standards,
and the instructions detailed in the Installation Manual.
Capacity shortage to the power supply circuit or improper
installation may result in malfunction, electric shock, smoke,
or fire.
To reduce the risk of electric shock, smoke, or fire, install an
earth leakage breaker on the power supply to each unit.
Use properly rated breakers and fuses (an earth leakage
breaker, local switch <a switch + fuse that meets local
electrical codes>, or overcurrent breaker).
The use of improperly rated breakers may result in electric
shock, malfunction, smoke, or fire.
To reduce the risk of current leakage, overheating, smoke, or
fire, use properly rated cables with adequate current carrying
capacity.
Keep the unsheathed part of cables inside the terminal
block.
If unsheathed part of the cables come in contact with each
other, electric shock, smoke, or fire may result.
Proper grounding must be provided by a qualified
personnel. 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.
Tighten all terminal screws to the specified torque.
Loose screws and contact failure may result in smoke or fire.
Only use standard power cables of sufficient capacity.
Failure to do so may result in current leakage, overheating,
smoke, or fire.
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.
To reduce the risk of electric shock, shorting, or malfunctions,
keep wire pieces and sheath shavings out of the terminal
block.
Transportation and repairs
The unit should be moved, disassembled, or repaired
only by qualified personnel. Do not alter or modify the
unit.
Improper repair or unauthorized modifications may result in
refrigerant leakage, water leakage, injury, electric shock, or
fire.
After disassembling the unit or making repairs, replace
all components as they were.
Failing to replace all components may result in injury, electric
shock, or fire.
If the supply cord is damaged, it must be replaced by the
manufacturer, its service agent or similarly qualified persons
in order to avoid a hazard.
To reduce the risk of shorting, electric shock, fire, or
malfunction, do not touch the circuit board with tools or with
your hands, and do not allow dust to accumulate on the
circuit board.
Do not open the control box cover while charging
refrigerant.
• If the refrigerant leaks, a fire may result.
IMPORTANT
To avoid damage to the unit, use appropriate 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 from the unit.
It is punishable by law to release refrigerant into the
atmosphere.
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Do not unnecessarily change the switch settings or
touch other parts in the refrigerant circuit.
Doing so may change the operation mode or damage the
unit.
To reduce the risk of malfunctions, use the unit within its
operating range.
Do not switch on or off the main power in a cycle of
shorter than 10 minutes.
Short-cycling the compressor may damage the compressor.
To maintain optimum performance and reduce the risk of
malfunction, keep the air pathway clear.
To ensure proper operation of the unit, periodically
check for proper concentration of anti-freeze.
Inadequate concentration of anti-freeze may compromise the
performance of the unit or cause the unit to abnormally stop.
Take appropriate measures against electrical noise
interference when installing the air conditioners in
hospitals or facilities with radio communication
capabilities.
Inverter, high-frequency medical, or wireless communication
equipment as well as power generators may cause the air
conditioning system to malfunction. Air conditioning system
may also adversely affect the operation of these types of
equipment by creating electrical noise.
Check the water system, using a relevant manual as a
reference.
Using the system that does not meet the standards (including
water quality and water flow rate) may cause the water pipes
to corrode.
To reduce the risk of power capacity shortage, 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.
When servicing the refrigerant, open and close the check
joint using two spanners, as there is the risk of
refrigerant leaking due to damaged piping.
Please build the water circuit so that it is a closed
system.
Do not use water directly for showers or other applications.
Do not allow other heat source water to mix with the water
circuit.
Store the unit in a room large enough to allow clearance
in the event of refrigerant leakage.
Refrigerant R454C is flammable. Do not use a naked-
flame type detector.
To protect the plate heat exchanger evacuate the system
and collect refrigerant with the pump in the water circuit
being operated.
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CONTENTS
HWE22020 GB
I Read Before Servicing
[1] Read Before Servicing.............................................................................................................. 3
[2] Necessary Tools and Materials ................................................................................................ 4
[3] Brazing...................................................................................................................................... 5
[4] Air Tightness Test..................................................................................................................... 6
[5] Vacuum Drying (Evacuation) .................................................................................................... 7
[6] Refrigerant Charging ................................................................................................................ 9
[7] Remedies to be taken in case of a Refrigerant Leak................................................................ 9
[8] Characteristics of the Conventional and the New Refrigerants .............................................. 10
[9] Precautions for handling equipment using R454C ................................................................. 11
[10] Notes on Refrigerating Machine Oil...................................................................................... 18
II Restrictions
[1] System Configuration ............................................................................................................. 21
[2] Types and Maximum allowable Length of Cables .................................................................. 22
[3] Main Power Supply Wiring and Switch Capacity .................................................................... 23
[4] Sample Installation ................................................................................................................. 27
[5] Switch Types and the Factory Settings .................................................................................. 28
[6] Configuring the Settings ......................................................................................................... 29
[7] Water Pipe Installation............................................................................................................ 36
III Unit Components
[1] Unit Components and Refrigerant Circuit ............................................................................... 43
[2] Control Box of the Unit............................................................................................................ 45
[3] Unit Circuit Board.................................................................................................................... 46
IV Remote Controller
[1] Using the Remote Controller .................................................................................................. 55
V Electrical Wiring Diagram
[1] Electrical Wiring Diagram ....................................................................................................... 67
VI Refrigerant Circuit
[1] Refrigerant Circuit Diagram .................................................................................................... 73
[2] Principal Parts and Functions ................................................................................................. 74
VII Control
[1] Functions and Factory Settings of the Dip switches ............................................................... 79
[2] Operating characteristics and Control Capabilities................................................................. 96
VIII Test Run Mode
[1] Items to be checked before a Test Run................................................................................ 113
[2] Test Run Method .................................................................................................................. 115
[3] Operating the Unit................................................................................................................. 116
[4] Refrigerant ............................................................................................................................ 117
[5] Symptoms that do not Signify Problems............................................................................... 117
[6] Standard operating characteristics (Reference data) ........................................................... 117
IX Maintenance
[1] Periodic maintenance inspections ........................................................................................ 121
[2] Guidelines for Maintenance and Inspection of Major Parts .................................................. 122
X Troubleshooting
[1] Maintenance items................................................................................................................ 127
[2] Troubleshooting .................................................................................................................... 135
[3] Troubleshooting Principal Parts............................................................................................ 141
[4] Refrigerant Leak ................................................................................................................... 158
[5] Parts Replacement Procedures............................................................................................ 159
XI USB Function
[1] Service Overview.................................................................................................................. 175
[2] Software Rewrite Function on the USB ................................................................................ 177
[3] Maintenance LED Display and Troubleshooting................................................................... 179
XII Attachments
[1] R454C saturation temperature table..................................................................................... 185
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CONTENTS
HWE22020 GB
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HWE22020 GB
I Read Before Servicing
[1] Read Before Servicing.......................................................................................................3
[2] Necessary Tools and Materials.......................................................................................... 4
[3] Brazing............................................................................................................................... 5
[4] Air Tightness Test..............................................................................................................6
[5] Vacuum Drying (Evacuation) .............................................................................................7
[6] Refrigerant Charging.......................................................................................................... 9
[7] Remedies to be taken in case of a Refrigerant Leak.........................................................9
[8] Characteristics of the Conventional and the New Refrigerants .......................................10
[9] Precautions for handling equipment using R454C........................................................... 11
[10] Notes on Refrigerating Machine Oil................................................................................. 18
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[ I Read Before Servicing ]
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I Read Before Servicing
[1] Read Before Servicing
1. Check the type of refrigerant used in the system to be serviced.
Refrigerant Type
Hot water Heat pump CAHV-R450YA-HPB:R454C
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 refrigerant.
Refer to "Necessary Tools and Materials" for information on the use of tools.(page 4)
5. 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.
CAUTION
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.
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[2] Necessary Tools and Materials
Prepare the following tools and materials necessary for servicing the unit.
Tools for use with R454C (Adaptability of tools that are for use with R22 or R410A)
1. To be used exclusively with R454C (not to be used if used with R22 or R410A)
2. Tools and materials that may be used with R454C with some restrictions
3. Tools and materials that are used with R22 or R410A that may also be used with R454C
4. Tools and materials that must not be used with R454C
Tools for R454C 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 4.82MPa on the high-
pressure side
Charging Hose Evacuation and refrigerant charging
Refrigerant Recovery Cylinder Refrigerant recovery
Refrigerant Cylinder Refrigerant charging The refrigerant type is indicated. The
cylinder is White
Charging Port on the Refrigerant Cylinder Refrigerant charging
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.
Refrigerant Recovery Equipment Refrigerant recovery May be used if compatible with
R454C.
Tools/Materials Use Notes
Vacuum Pump with a Check Valve Vacuum drying
Bender Bending pipes
Torque Wrench Tightening water pipes
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
Tools containing abrasive materials Pipe cutting, cut edge treatment Prohibited to use
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[3] 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 non-oxidized solder.
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 hygroscopic 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 oxidized solder for brazing Use of non-oxidized solder for brazing
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[4] Air Tightness Test
No changes have been made in the detection method. Note that a refrigerant leak detector for R22 will not detect an R454C leak.
1. Items to be strictly observed
Pressurize the equipment with nitrogen up to the design pressure (3.85MPa), and then judge the equipment's air tightness,
taking temperature variations into account.
Refrigerant R454C 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 R454C 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(R454C) leak.
Halide torch R22 leakage detector
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[5] Vacuum Drying (Evacuation)
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.) When the outside temperature drops below 1°C (or when the saturation pressure drops below
656 Pa), continue vacuum drying for another 1 hour after the vacuum degree has reached the saturated vapor pressure of
the water (ice) at the outside temperature. When performing vacuum drying at a low outside temperature, use a vacuum gauge
appropriate for the temperature range.
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.)
(Photo1) 15010H (Photo2) 14010
Recommended vacuum gauge:
ROBINAIR 14010 Thermistor Vacuum Gauge
Degree of vacuum (reference)
Outdoor temp. -20°C (-4°F) -15°C (5°F) -10°C (14°F) -5°C (23°F) 0°C (32°F)
Degree of vacuum 0.77 Torr (103 Pa) 1.24 Torr (165 Pa) 1.95 Torr (260 Pa) 3.01 Torr (402 Pa) 4.58 Torr (611 Pa)
* Degrees of vacuum shown above are obtained based on the saturated vapor pressure of ice.
* In a system using water heat exchangers, circulate water to prevent the water in the heat exchangers from freezing during vacuum drying.
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HWE22020 GB
7. Notes
To evacuate air only from the outdoor units
Apply a vacuum through the check joints on the low pressure sides.
Evacuating the system from the high-pressure side may damage the compressor.
When dry-vacuuming and recovering refrigerant, let the water circulate to keep the plate heat exchanger from freez-
ing.
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HWE22020 GB
[6] Refrigerant Charging
1. Reasons
R454C is a mixture of 2 refrigerants, each with a different evaporation temperature. Therefore, if the equipment is charged
with R454C gas, then the refrigerant whose evaporation temperature is closest to the outside temperature is charged frist
while the rest of refrigerants remain in the cylinder.
2. Notes
When using a cylinder with a siphon, refrigerant is charged in the liquid state without the need for turning it upside down. Check
the type of the cylinder on the label before use.
[7] Remedies to be taken in case of a Refrigerant Leak
If the refrigerant leaks out, all of the remaining refrigerant must be replaced with a new charge to maintain the proper composition
of the refrigerant. Repair the leak, and then charge the system with the specified amount of refrigerant (9.0 kg). (Charge refrigerant
in the liquid state.)
Refer to "X [4] Refrigerant Leak."(page 158)
Cylinder with a siphon
Cylinder color R454C is White. Refrigerant charging in the liquid state
Charge refrigerant through the
check joint on the high-pressure side.
Charging refrigerant through the
check joint on the low-pressure side
will create reverse pressure,
resulting in compressor malfunctions.
Cylin-
der
liquid
Valve Valve
liquid
Cylin-
der
Cylinder without a siphon
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[8] Characteristics of the Conventional and the New Refrigerants
1. Chemical property
As with R22, the new refrigerant (R454C) is low in toxicity and slightly flammable 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 CO2 is used as a reference
2. Pressure characteristics
The pressure in the system using R454C is 0.9 times as great as that in the system using R22.
New Refrigerant (HFC type) Conventional Re-
frigerant (HCFC
type)
R410A R407C R454C R22
R32/R125 R32/R125/R134a R32/R1234yf R22
Composition (wt%) (50/50) (23/25/52) (21.5/78.5) (100)
Type of Refrigerant Pseudo-azeo-
tropic
Refrigerant
Non-azeotropic
Refrigerant
Non-azeotropic
Refrigerant
Single Refrigerant
Chloride Not included Not included Not included Included
Safety Class A1/A1 A1/A1 A2L/A2L A1
Molecular Weight 72.6 86.2 90.8 86.5
Boiling Point (°C/°F) -51.4/-60.5 -43.6/-46.4 -45.9/-50.6 -40.8/-41.4
Steam Pressure
(25°C,MPa/77°F,psi) (gauge)
1.56/226 0.92/133 0.88/127 0.94/136
Saturated Steam Density
(25°C,kg/m3/77°F,psi)
64.0 42.5 44.5 44.4
Flammability Nonflammable Nonflammable Slightly flammable Nonflammable
Ozone Depletion Coefficient (ODP)*1 0 0 0 0.055
Global Warming Coefficient (GWP)*2 1920 1624 146 1760
Refrigerant Charging Method Refrigerant
charging in the l
iquid state
Refrigerant
charging in the
liquid state
Refrigerant
charging in the
liquid state
Refrigerant
charging in the
gaseous state
Replenishment of Refrigerant after
a Refrigerant Leak
Available Available Non available Available
Temperature (°C/°F)
Saturation Pressure (gauge)
R410A R407C R454C R22
MPa/psi MPa/psi MPa/psi MPa/psi
-20/-4 0.30/44 0.18/26 0.12/17 0.14/20
0/32 0.70/102 0.47/68 0.35/51 0.40/58
20/68 1.34/194 0.94/136 0.75/108 0.81/117
40/104 2.31/335 1.44/209 1.36/197 1.44/209
60/140 3.73/541 2.43/354 2.27/329 2.33/338
65/149 4.17/605 2.74/399 2.55/370 2.60/377
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HWE22020 GB
[9] Precautions for handling equipment using R454C
When handling the units that use R454C refrigerant, observe the following notes. (The notes are based on the precautions
regarding R454C refrigerant contained in IEC 60335-2-40.)
1. General
Compliance with national gas regulations shall be observed.
2. Transportation
1) Additional transportation regulations may exist with respect to equipment containing slightly flammable gas.
3. Disposal
1) Follow the local regulations on proper disposal of equipment using R454C.
4. Storage
1) Store the unit in a sufficiently large space so that leaked refrigerant will not stagnate in a small confined area.
2) The maximum number of pieces of equipment permitted to be stored together will be determined local regulations.
5. Servicing information
1) Checks to the area
Prior to beginning work on systems containing slightly flammable refrigerants, safety checks are necessary to ensure that the
risk of ignition is minimised. For repair to the refrigerating system, 3) to 7) shall be completed prior to conducting work on the
system.
2) Work procedure
Work shall be undertaken under a controlled procedure so as to minimise the risk of a slightly flammable gas being present
while the work is being performed.
3) General work area
All maintenance staff and others working in the local area shall be instructed on the nature of work being carried out. Work in
confined spaces shall be avoided. The area around the workspace shall be sectioned off. Ensure that the conditions within the
area have been made safe by control of flammable material.
4) Checking for presence of refrigerant
The area shall be checked with an appropriate refrigerant detector prior to and during work, to ensure the technician is aware
of potentially slightly flammable atmospheres. Ensure that the leak detection equipment being used is suitable for use with all
applicable refrigerants.
5) Presence of fire extinguisher
If any hot work is to be conducted on the refrigeration equipment or any associated parts, appropriate fire extinguishing
equipment shall be available to hand. Have a dry powder or CO2 fire extinguisher adjacent to the charging area.
6) No ignition sources
No person carrying out work, such as brazing, in relation to a refrigeration system which involves exposing any pipe work shall
use any sources of ignition in such a manner that it may lead to the risk of fire or explosion. All possible ignition sources,
including cigarette smoking, should be kept sufficiently far away from the site of installation, repairing, removing and disposal,
during which refrigerant can possibly be released to the surrounding space. Prior to work taking place, the area around the
equipment is to be surveyed to make sure that there are no flammable hazards or ignition risks. ''No Smoking'' signs shall be
displayed in a conspicuous place in the work area.
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