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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6
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.
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1. Selecting the Installation Site
[1] Installation Conditions
Select the installation site in consultation with the client.
Select a site to install the outdoor unit that meets the following conditions:
• The unit will not be subject to heat from other heat sources.
• The noise from the unit will not be a problem.
• The unit will not be exposed to strong winds.
• Water from the unit can be drained properly.
• The space requirements (specified on pages 8 through 10) are met.
<1> Providing protection against winds
Using the figures at right as a reference,
provide adequate protection against
winds.
A unit installed alone is vulnerable to
strong winds. Select the installation site
carefully to minimize the effect of winds.
When installing a unit in a place where
the wind always blows from the same
direction, install the unit so that the outlet
faces away from the direction of the
wind.
<2> Cold Climate Installation
Observe the following when installing the units in areas where snow or strong winds prevail.
• Avoid direct exposure to rain, winds, and snow.
• Icicles that may form under the foundation can fall and inflict personal injury or property damage. Select the
installation site carefully to reduce these risks, especially when installing the unit on a roof.
• If the units are installed in the direct line of rain, winds, or snow, install snow hoods (on both the discharge and
suction ducts). Use a snow net or snow fence as necessary to protect the unit.
• Install the unit on a base approximately twice as high as the expected snowfall.
• If the unit is continuously operated for a long time with the outside air temperature below the freezing point, install
a heater at the base of the unit to prevent the water from freezing at the unit bottom.
• Install snow hoods in regions where the outdoor temperature is -10°C or below.
Wind
Wind Wind
• Install the outdoor unit in a place
where it is not exposed to direct wind,
such as behind a building.
• Install the outdoor
unit so that the outlet/
inlet faces away from
the wind.
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[2] Installation Space Requirements
<1> Single unit installation
Secure enough space around the unit as shown in the figures below.
<Unit: mm>
(1) Walls around the unit do not exceed the height limit.
(2) There is a wall above the unit.
(3) One or more of the walls around the unit are taller than the maximum allowable height <h>.
Max. 500
300
Min. 500
A
80
A
80
AWalls are lower than the unit's height.
300
Min. 240
Min. 45º
Min. 1000
Flow hood
(field supplied)
Max. 500
300
Min. 500 + h
A
80
A
80
Min. 500 + h
Max. 500
300 + h
A
80
A
80
h
Min. 500 + h
Max. 500
300 + h
A
80
A
80 h
AWalls are lower than the unit's height.
h
h
h
h
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9
(4) Water pipe installation
<2> Grouped and side-by-side installation
When multiple units are installed adjacent to each other, allow enough space for air circulation and a walk way
between groups of units as shown in the figures below.
* Leave both sides of each group of units open.
As with individual installation, if the wall height exceeds the height limit, widen the space in the front and the back of a
given group of units by the amount that exceeds the limit (labeled <h> in the figure).
<Unit: mm>
(1) Side-by-side installation
(2) Face-to-face installation
* Min. 300
* Min. 500
Min. 80Min. 80
Front
Wall
<Top view> <Side view>
X
X
* Min. 300
* Min. 500
Min. 80Min. 80
Front Wall
<Top view> <Side view>
Water pipeFoundation
Leave a space of at least 500 between the unit and the
water pipe if it is not possible to install the unit on a
raised foundation. (See in the figure.)
Water pipe
Max. 500
*
Min. 500 + h
Min. 160 h
Min. 300 + h
h
Unit height
*
• There are walls in the back and the front of a given
group of units.
Min. 300 + h
Min. 500
Min. 500
Min. 500
500
h
h
Unit height
*
*
• There is a wall on one side.
Min. 500
Min. 500
Min. 80 + h
h
Unit height
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10
(3) Combination of face-to-face and side-by-side installations
(4) Water pipe installation
• There are walls in the back and the front of a given
group of units.
Min. 300 + h
Min. 900
500
h
*
*
Min. 300 + h
500
h
• There is a wall on one side and either the front or
the back of a given group of unit.
Min. 1000 + h
h
Unit height
500
h
Min.
300 + h
*
*
Min. 900
If the product width (labeled A in the figure) times
the number of units that are installed side by side
exceeds 6 m, leave a space of 1000 mm
between each block. Each block is defined as a
group of units that fit within 6 m.
Min. 160
Water pipe
Front
Wall
<Top view> <Side view>
Wall
Front Front
Wall
A
Min. 160A
Water pipe
If the product depth (labeled B in the figure) times the
number of units that are installed in rows exceeds 6 m,
leave a space of 1000 mm between each block. Each
block is defined as a group of units that fit within 6 m.
Min. 500
Water pipe
Front
Wall
<Top view> <Side view>
Wall
Front
BMin.500
Front
Min. 500
Front
Min. 500
Front
Min. 300
Wall
Pattern BPattern A
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11
2. Unit Installation
Units should be installed only by personnel certified by Mitsubishi Electric.
• Securely fix the unit with bolts to keep the unit from falling down during earthquakes or due to strong winds.
• Install the unit on a foundation made of concrete or iron.
• Noise and vibrations from the unit may be transmitted through the floor and walls. Provide adequate protection
against noise and vibration.
• Build the foundation in such way that the corners of the installation legs are securely supported as shown in the
figure below. When using rubber vibration isolators, make sure they are large enough to cover the entire width of
the unit's legs. If the corners of the legs are not firmly seated, the legs may bend.
• The projecting length of the anchor bolt should be less than 30 mm.
• This unit is not designed to be installed using hole-in anchor bolts unless brackets are used to support the four
corners of the unit.
• The legs on the unit are detachable.
• Detaching the legs
Loosen the three screws on the legs to detach each leg (two each in the front and back). If the finish coat becomes
damaged when detaching the legs, be sure to touch it up.
• With some types of installation, unit vibration and sound will be transmitted to the floors and walls.
Excessive vibrations can damage the pipes, resulting in refrigerant gas leakage. Take measures to prevent
vibration (such as using anti-vibration rubber pads).
Warning:
• Install the unit in accordance with the instructions to minimize the risk of damage from earthquakes and
strong winds.
- Improper installation will cause the unit to topple, resulting in serious injury.
To reduce the vibration of the unit operation, irrespective of the cause of the vibration such as earthquakes and
strong winds, perform the foundation work in accordance with the installation instructions (including the
instructions for installing anti-vibration rubber pads) provided in this section.
• The unit must be securely installed on a structure that can sustain its weight.
- Failure to do so will cause the unit to fall, resulting in serious injury. Abnormal vibrations that result from improper
installation can generate abnormal sound and damage the pipes, resulting in refrigerant gas leakage.
Take adequate measures against typhoon winds and earthquakes so that the unit will not fall or tip over. Consult
the local specialists for safety measures to be taken.
When building the foundation, take the floor strength, water drainage during operation, and piping and wiring routes
into consideration.
Precautions for routing the pipes and wires underneath the unit without detachable legs
When routing the pipes and wires underneath the unit, make sure that the foundation will not block the piping access
holes. Also, make sure the foundation is at least 100 mm high so that the piping can pass under the unit.
A: M10 anchor bolt (field supply)
B: Corner is not seated.
C: Detachable leg
D: Screws
≤30 mm
A
≤30 mm
A
B
B
C
D
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3. Water Pipe Installation
[1] Schematic Piping Diagram and Piping System Components
1Union joints/flange joints Required to allow for a replacement of equipment.
2Thermometer Required to check the performance and monitor the operation of the units.
3Water pressure gauge Recommended for checking the operation status.
4Valve Required to allow for a replacement or cleaning of the flow adjuster.
5Flexible joint Recommended to prevent the noise and vibration from the pump from being transmitted.
6Pump Use a pump that is large enough to compensate for the total water pressure loss and
supply sufficient water to the unit.
7Automatic air vent valve
Install automatic air vent valves where air accumulates.
Even in the case of a failure of the water-side heat exchanger in the unit, the refrigerant
may leak from the automatic air vent valve.
To prevent accidents resulted from refrigerant leakage, install the unit where leaked
refrigerant will not accumulate, such as outdoors.
8Closed expansion tank Install a closed expansion tank to accommodate expanded water and to supply water.
9Water pipe Use pipes that allow for easy air purging, and provide adequate insulation.
0Drain valve Install drain valves so that water can be drained for servicing.
aStrainer Install a strainer near the unit to keep foreign materials from entering the water-side
head exchanger.
bFlow switch Required to protect the unit.
cDrain pipe
Install the drain pipe with a downward inclination of between 1/100 and 1/200. To
prevent drain water from freezing in winter, install the drain pipe as steep an angle as
practically possible and minimize the straight line.
For cold climate installation, take an appropriate measure (e.g., drain heater) to prevent
the drain water from freezing.
dCheck valve Required to prevent the backward flow.
eSafety valve
Install a safety valve near the closed expansion tank.
Even in the case of a failure of the water-side heat exchanger in the unit, the refrigerant
may leak from the safety valve.
To prevent accidents resulted from refrigerant leakage, install the unit where leaked
refrigerant will not accumulate, such as outdoors.
c
Indicates the direction of
the flow.
Unit
Water
side heat
exchanger
Air conditioning
floor heating
etc
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13
[2] Notes on Pipe Corrosion
Water treatment and water quality control
Poor-quality circulating water can cause the water-side heat exchanger to scale up or corrode, reducing heat-
exchange performance. Properly control the quality of the circulating water.
• Removing foreign objects and impurities in the pipes
During installation, keep foreign objects, such as welding and sealant fragments and rust, out of the pipes.
• Water Quality Control
(1) Poor-quality water can corrode or scale up the heat exchanger. Regular water treatment is recommended.
Water circulation systems using open heat storage tanks are particularly prone to corrosion.
When using an open heat storage tank, install a water-to-water heat exchanger, and use a closed-loop circuit
on the hot water heat pump unit side. If a water supply tank is installed, keep contact with air to a minimum, and
keep the level of dissolved oxygen in the water no higher than 1 mg/ℓ.
(2) Water quality standard
Reference: Guideline of Water Quality for Refrigeration and Air Conditioning Equipment. (JRA GL02E-1994)
(3) Please consult with a water quality control specialist about water quality control methods and water quality
calculations before using anti-corrosive solutions for water quality management.
(4) When replacing a hot water heat pump unit (including when only the heat exchanger is replaced), first analyze
the water quality and check for possible corrosion.
Corrosion can occur in water systems in which there has been no signs of corrosion. If the water quality level
has dropped, adjust the water quality before replacing the unit.
Items
Lower mid-range temperature water system
Water Temp. ≤60ºC
Higher mid-range temperature water system
Water Temp. > 60ºC
Tendency
Recirculating water Make-up water Recirculating water Make-up water Corrosive Scale-
forming
Standard
items
pH (25˚C) 7.0 ~ 8.0 7.0 ~ 8.0 7.0 ~ 8.0 7.0 ~ 8.0
Electric conductivity (mS/m) (25˚C) 30 or less 30 or less 30 or less 30 or less
(µs/cm) (25˚C) [300 or less] [300 or less] [300 or less] [300 or less]
Chloride ion (mg Cl-/ℓ)50 or less 50 or less 30 or less 30 or less
Sulfate ion (mg SO42-/ℓ)50 or less 50 or less 30 or less 30 or less
Acid consumption
50 or less 50 or less 50 or less 50 or less
(pH4.8) (mg CaCO3/ℓ)
Total hardness (mg CaCO3/ℓ)70 or less 70 or less 70 or less 70 or less
Calcium hardness (mg CaCO3/ℓ)50 or less 50 or less 50 or less 50 or less
Ionic silica (mg SiO2/ℓ)30 or less 30 or less 30 or less 30 or less
Reference
items
Iron (mg Fe/ℓ) 1.0 or less 0.3 or less 1.0 or less 0.3 or less
Copper (mg Cu/ℓ) 1.0 or less 0.1 or less 1.0 or less 0.1 or less
Sulfide ion (mg S2-/ℓ)Not to be detected Not to be detected Not to be detected Not to be detected
Ammonium ion (mg NH4+/ℓ)0.3 or less 0.1 or less 0.1 or less 0.1 or less
Residual chlorine (mg Cl/ℓ) 0.25 or less 0.3 or less 0.1 or less 0.3 or less
Free carbon dioxide (mg CO2/ℓ)0.4 or less 4.0 or less 0.4 or less 4.0 or less
Ryzner stability index — — — —
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14
(5) Suspended solids in the water
Sand, pebbles, suspended solids, and corrosion products in water can damage the heating surface of the heat
exchanger and cause corrosion. Install a good quality strainer (20 mesh or better) at the inlet of the unit to filter
out suspended solids.
Removing foreign substances from the water system
Consider installing a settlement tank or a bypass strainer to remove foreign substances from the water system.
Select a strainer capable of handling two to three percent of the circulating water. The figure below shows a
sample system with a bypass strainer.
(6) Connecting pipes made from different materials
If different types of metals are placed in direct contact with each other, the contact surface will corrode.
Install an insulating material between pipes that are made of different materials to keep them out of direct
contact with each other.
Air conditioning unit
Heat pump unit
Strainer (20 mesh or its equivalent)
Water pump
Bypass strainer
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15
[3] Installing the Strainer and Flow Switch
<1> Installing the strainer
Install the supplied strainer on the inlet water pipe near the unit to filter out suspended solids and prevent clogging or
corrosion of the heat exchanger.
Install the strainer in a way that allows for easy access for cleaning, and instruct the user to clean it regularly.
Operating the units with a clogged strainer may cause the units to make an abnormal stop.
Select a location to install a strainer, taking into consideration the installation angle, insulation thickness, and
maintenance space.
* The dimensions given below indicate the amount of space necessary when screwing in a Y-shaped strainer.
<2> Installing a flow switch
Install a flow switch that meets the following specifications on the water pipe.
Connect the flow switch to the flow switch contact on the unit.
Minimum flow rate= 1.5 m³/h (25 L/min)
Unit usage range (water flow rate): 1.5 - 15.0 m³/h *
* 4.0 - 15.0 m3/h under the following conditions:
a. When the outdoor temperature is below 0°C,
b. When the outlet water temperature is 30°C or below AND the outdoor temperature is 6°C or below.
Rc1 1/2
160
115
100
Y-shaped strainer
(supplied)
Pipes
(field-supplied)
Min. 110
Y-shaped strainer
maintenance access space
153
Sample installation 1 Sample installation 2
Min. 110
* Min. 43
Max. 25º
Y-shaped strainer
maintenance access space
Y-shaped strainer
(supplied)
Pipes (field-supplied)
<Unit: mm>
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16
[4] Water Pipe Hole Size and Location
Water pipe groove specifications
Housing joint
Water inlet <40A housing type joint> Water outlet <40A housing type joint>
1410
426
155
dG
LW
(Unit: mm)
Pipe size
1-1/2B (40A)
d ø48.3±0.3
Gø45
W8±0.3
L 15.9±0.3
0
-0.3
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17
4. System Configurations
[1] Schematic Diagrams of Individual and Multiple Systems
(1) Individual system
(2) Multiple system (2-16 units)
Refer to the sections "Switch Types and the Factory Settings" on the next page and
"System configuration procedures: Individual system" (page 22) for further details.
Refer to the sections "Switch Types and the Factory Settings" on the next page
and "System configuration procedures: Multiple system" (page 23) for further details.
PCB External
temperature
sensor
Field-supplied dry
contact switch/relay
or remote controller
Field-supplied dry
contact switch/relay
or remote controller
External
temperature
sensor
PCB
* Each unit is operated individually by connecting a dry contact switch/relay to each unit.
Sub box Sub box
External
temperature
sensor
Field-supplied dry
contact switch/relay
or remote controller
MAIN unit SUB unit SUB unit(s)
"n"th unit
Inter-unit wiring
(M-NET line)
Inter-unit wiring
(M-NET line)
PCB PCB PCB
* A group of unit that consists of one main unit and up to 15 sub units is operated collectively by connecting an external water temperature sensor and a dry
contact switch/relay to the main unit.
Sub box
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18
[2] Switch Types and the Factory Settings
(1) Switch names and functions
There are four main ways to set the settings as follows:
1Dip switches (SW4 - SW7)
2Dip switches used in combination with the push switches
3Rotary switches
4Slide switches
See below for how these switches are used to set certain items.
Different types of switches on the PCB
Initial Setting
MAIN circuit
Rotary switch (SWU1) Sets the 1's digit of the unit address (Multiple system). "1"
Rotary switch (SWU2) Sets the 10's digit of the unit address (Multiple system). "0"
Slide switch (SWS1)
REMOTE
OFF
LOCAL
The action that the switch takes when set to a certain position depends
on the type of system configuration (e.g., individual or multiple system) REMOTE
Slide switch (SWS2) Unused A
Push switch (SWP1) Switches the display between the item code and the current value for a specific item.
Increases value. -
Push switch (SWP2) Switches the display between the item code and the current value for a specific item.
Decreases value. -
Push switch (SWP3) Advances the item code.
Saves the changed value. -
Dip switches (SW4-7) Switches the LED display contents.
Control box
Service panel
Water outlet
Water inlet
Sub box
Discharge air outlet
Intake air inlet
Service panel
Rotary switch (SWU2) (0-9)
Rotary switch (SWU1) (0-9)
Slide switch (SWS1)
(REMOTE, OFF, and
LOCAL from the top) Push switch (SWP1)
Push switch (SWP2)
Push switch (SWP3)
Slide switch (SWS2)
(A and B from the top)
Switches
[Entire view of a PCB] [Enlarged view of the switches]
LED display
Dip switch (SW4)
Dip switch (SW5)
Dip switch (SW6)
Dip switch (SW7)
Slide the dip
switches; do not
push down the
switches.
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19
(2) Factory Switch Settings (Dip switch settings table)
"-" in the table indicates that the function in the corresponding row will be disabled regardless of the actual switch setting.
The factory setting for these items is OFF.
Refer to page 27 for how to reset errors.
Factory setting
SW Function Usage Circuit board OFF setting ON setting Setting
timing
SW4
1
Model setting
Depends on the unit Leave the setting as it is. At a reset
2
3
4
5
6
7
8
9
10 Model setting OFF Leave the setting as it is. At a reset
SW5
1 Freeze-up protection setting OFF
Starts the pump when both
the outside and water
temperatures drop to
prevent water pipe freeze
up.
Same as when set to OFF At a reset
2Scheduled operation
display
Turns on and off the remote display during
scheduled operation. OFF
Leaves the operation
display on during the period
in which the unit is
scheduled to be stopped.
Turns off the operation
display during the period in
which the unit is scheduled
to be stopped.
At a reset
3 Model setting OFF Leave the setting as it is. At a reset
4 Model setting OFF Leave the setting as it is. At a reset
5Recovery conditions after
forced stoppage
Selects what the operation restoration
condition will be based on after the unit
was forced to stop based on the external
thermistor reading (water outlet
temperature).
OFF External thermistor Built-in thermistor At a reset
6Power supply option to the
communication circuit
Switches between supplying or not
supplying power to the communication
circuit.
-Does not supply power to
the communication circuit.
Supplies power to the
communication circuit. Any time
7Remote water-temperature
setting
Allows or disallows the water temperature
to be set using analog signals from a
remote location.
OFF
Disallows the water
temperature to be set using
external analog signals.
Allows the water
temperature to be set using
external analog signals.
At a reset
8Water-temperature control
option
Selects either the external water
temperature sensor or the built-in sensor
to be used to control water temperature.
OFF Built-in sensor on the unit External water temperature
sensor At a reset
9 Individual/Multiple system Selects between individual and Multiple
system OFF Individual system Multiple system At a reset
10 Display mode switch 7
This switch is used in combination with dip
switches SW6-5 through 6-10 and push
switches SWP 1, 2, and 3 to configure or
view the settings when performing a test
run or changing the system configuration.
OFF Changes the 7-segment LED display mode. Any time
SW6
1 Remote reset Enables or disables the error to be reset
from a remote location. ON
Disables the error to be
reset from a remote
location.
Enables the error to be
reset from a remote
location.
At a reset
2Auto restart after power
failure
Enables or disables the automatic
restoration of operation after power failure
(in the same mode as the unit was in
before a power failure).
ON
An alarm will be issued
when power is restored
after a power outage.
The alarm will be reset
when the power is turned off
and then turned back on.
Automatically restores
operation after power
failure.
At a reset
3 Water-temperature control
Switches between inlet-water-
temperature-based control and outlet-
water-temperature-based control.
OFF Outlet-water-temperature-
based control
Inlet-water-temperature-
based control At a reset
4Pump-thermistor interlock
setting
Interlocks or does not interlock the
operation of the pump with the external
thermistor.
(Effective only when SW5-8 is set to ON.)
OFF
The pump turns on when
the operation switch is
turned on regardless of the
Thermo-ON/Thermo-OFF
status.
Interlocks the operation of
the pump with the Thermo-
ON/Thermo-OFF status.
At a reset
5 Display mode switch 1
These switches are used in combination
with dip switches SW5-5 and push
switches SWP 1, 2, and 3 to configure or
view the settings when performing a test
run or changing the system configuration.
OFF Changes the 7-segment LED display mode. Any time
6 Display mode switch 2 OFF Changes the 7-segment LED display mode. Any time
7 Display mode switch 3 OFF Changes the 7-segment LED display mode. Any time
8 Display mode switch 4 OFF Changes the 7-segment LED display mode. Any time
9 Display mode switch 5 OFF Changes the 7-segment LED display mode. Any time
10 Display mode switch 6 OFF Changes the 7-segment LED display mode. Any time
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20
[3] Configuring the Settings
<1> Making the settings
Use the LED display and the three push switches (SWP1 (↑), SWP2 (↓), and SWP3 (Enter)) to change the current
settings on the circuit board and to monitor various monitored values.
(1) Setting procedures
Take the following steps to set the push switches SWP1 through SWP3. These switches must be set after the dip
switches SW5 and SW6 have been set.
The settings must be set only by a qualified personnel.
1Normally an item code appears on the display.
(The figure at left shows the case where item code 1 is displayed.) Press SWP3
(Enter) to advance the item code.
↓
Press SWP3 (Enter) until the item code appears that corresponds to the item to change or
monitor its value.
2The left figure shows a display example (Code 13 Built-in thermistor temperature
setting 2).
↓
Press either SWP1 (↑) or SWP2 (↓) to display the value that corresponds to the
selected item.
3The current setting value will blink.
↓
The left figure shows that the current setting value is "60.0."
To decrease this value to 58.0, for example, press SWP2 (↓).
Press SWP1 (↑) to increase the value.
4<To change the settings>
When the desired value is displayed (58.0 in the example at left), press SWP3 (Enter).
↓
The displayed value will stop blinking and stay lit.
A lit LED indicates that the new setting has been saved.
* Pressing SWP1 (↑) or SWP2 (↓) will change the blinking setting value, but the
change will not be saved until SWP3 (Enter) is pressed.
If SWP3 is not pressed within one minute, the change will not be saved and the
display will return to the item code display mode.
Press and hold SWP1 (↑) or SWP2 (↓) for one second or longer to fast forward
through the numbers.
<To view the monitored data>
Press SWP3 (Enter) while the LED display is blinking (see step 3 above) to stop the
blinking.
* The values of the items that can only be monitored will not change when SWP1 (↑)
or SWP2 (↓) is pressed.
The display will stop blinking and stay lit after a minute, and the display will
automatically return to the item code display regardless of the type of values
displayed.
To change the values of other items, repeat the steps from step 2 above.
SWP1
SWP3
Enter
SWP2
SWP1
SWP3
Enter
SWP2
SWP1
SWP3
Enter
SWP2
SWP1
SWP3
Enter
SWP2
WT09871X01.book 20 ページ ２０２２年７月６日 水曜日 午前１１時４４分