Mitsubishi Electric CAHV-R450YA-HPB User manual

CONTENTS
Safety Precautions ................................................................2
1. Selecting the Installation Site ............................................7
[1] Installation Conditions...................................................7
[2] Installation Space Requirements ..................................8
2. Unit Installation ................................................................11
3. Water Pipe Installation.....................................................12
[1] Schematic Piping Diagram and Piping System
Components ...............................................................12
[2] Notes on Pipe Corrosion.............................................13
[3] Installing the Strainer and Flow Switch.......................15
[4] Water Pipe Hole Size and Location ............................16
4. System Configurations ....................................................17
[1] Schematic Diagrams of Individual and Multiple
Systems ......................................................................17
[2] Switch Types and the Factory Settings.......................18
[3] Configuring the Settings..............................................20
5. Electrical Wiring Installation.............................................43
[1] Main Power Supply Wiring and Switch Capacity ........43
[2] Cable Connections......................................................45
6. Troubleshooting...............................................................52
[1] Diagnosing Problems for which No Error Codes Are
Available .....................................................................52
[2] Diagnosing Problems Using Error Codes ...................53
[3] Calling for Service.......................................................57
7. Operating the Unit ...........................................................58
[1] Initial Operation...........................................................58
[2] Daily Operation ...........................................................58
[3] Using the Remote Controller.......................................59
[4] Using the Unit in Sub-freezing or Snowy Conditions ..69
8. Main Specifications..........................................................70
9. Maintenance ....................................................................72
[1] Guidelines for Maintenance and Inspection of Major
Parts ...........................................................................72
Hot Water Heat Pump Unit CAHV
Installation/Operation Manual
For use with R454C
CAHV-R450YA-HPB(-BS)
Thoroughly read this manual prior to use.
Save this manual for future reference.
Some of the items in this manual may not apply to made-to-order units.
Make sure that this manual is passed on to the end users.
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2
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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4
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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