Mitsubishi Electric PAC-TZ02-E User manual

SERVICE MANUAL
Notes:
•This manual describes ser-
vice data of 2 zone kit only.
PARTS CATALOG (OCB729)
2 ZONE KIT
[Model Name]
PAC-TZ02-E
[Service Ref.]
PAC-TZ02-E
November 2019
2 ZONE KIT
No. OCH729
CONTENTS
1. REFERENCE MANUAL...........................2
2. SAFETY PRECAUTION ..........................3
3. SPECIFICATIONS....................................4
4. PARTS NAMES AND FUNCTIONS.........5
5. OUTLINES AND DIMENSIONS...............6
6. WIRING DIAGRAM..................................7
7. TROUBLESHOOTING.............................8
8. DISASSEMBLY PROCEDURE................ 10

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OCH729
REFERENCE MANUAL
1
Model Name Service Ref. Service Manual No.
EHSD-MED EHSD-MED.UK
OCH712
OCB712
EHSD-VM2D EHSD-VM2D.UK
EHSD-VM6D EHSD-VM6D.UK
EHSD-YM9D EHSD-YM9D.UK
EHSD-YM9ED EHSD-YM9ED.UK
EHSD-TM9D EHSD-TM9D.UK
ERSD-MED ERSD-MED.UK
ERSD-VM2D ERSD-VM2D.UK
EHSC-MED EHSC-MED.UK
EHSC-VM2D EHSC-VM2D.UK
EHSC-VM6D EHSC-VM6D.UK
EHSC-YM9D EHSC-YM9D.UK
EHSC-YM9ED EHSC-YM9ED.UK
EHSC-TM9D EHSC-TM9D.UK
ERSC-MED ERSC-MED.UK
ERSC-VM2D ERSC-VM2D.UK
EHPX-MED EHPX-MED.UK
EHPX-VM2D EHPX-VM2D.UK
EHPX-VM6D EHPX-VM6D.UK
EHPX-YM9D EHPX-YM9D.UK
EHPX-YM9ED EHPX-YM9ED.UK
EHST17D-VM2D EHST17D-VM2D.UK
OCH714
OCB714
ERST17D-VM2D ERST17D-VM2D.UK
EHST20D-MED EHST20D-MED.UK
EHST20D-VM2D EHST20D-VM2D.UK
EHST20D-VM6D EHST20D-VM6D.UK
EHST20D-YM9D EHST20D-YM9D.UK
EHST20D-YM9ED EHST20D-YM9ED.UK
EHST20D-TM9D EHST20D-TM9D.UK
ERST20D-VM2D ERST20D-VM2D.UK
EHST30D-MED EHST30D-MED.UK
EHST30D-VM6ED EHST30D-VM6ED.UK
EHST30D-YM9ED EHST30D-YM9ED.UK
EHST30D-TM9ED EHST30D-TM9ED.UK
ERST30D-VM2ED ERST30D-VM2ED.UK
EHST20C-MED EHST20C-MED.UK
EHST20C-VM2D EHST20C-VM2D.UK
EHST20C-VM6D EHST20C-VM6D.UK
EHST20C-YM9D EHST20C-YM9D.UK
EHST20C-YM9ED EHST20C-YM9ED.UK
EHST20C-TM9D EHST20C-TM9D.UK
ERST20C-VM2D ERST20C-VM2D.UK
EHST30C-MED EHST30C-MED.UK
EHST30C-VM6ED EHST30C-VM6ED.UK
EHST30C-YM9ED EHST30C-YM9ED.UK
EHST30C-TM9ED EHST30C-TM9ED.UK
ERST30C-VM2ED ERST30C-VM2ED.UK
EHPT17X-VM2D EHPT17X-VM2D.UK
EHPT17X-VM6D EHPT17X-VM6D.UK
EHPT17X-YM9D EHPT17X-YM9D.UK
ERPT17X-VM2D ERPT17X-VM2D.UK
EHPT20X-MED EHPT20X-MED.UK
EHPT20X-VM6D EHPT20X-VM6D.UK
EHPT20X-YM9D EHPT20X-YM9D.UK
EHPT20X-YM9ED EHPT20X-YM9ED.UK
EHPT20X-TM9D EHPT20X-TM9D.UK
EHPT20X-MHEDW EHPT20X-MHEDW.UK
ERPT20X-MD ERPT20X-MD.UK
ERPT20X-VM2D ERPT20X-VM2D.UK
ERPT20X-VM6D ERPT20X-VM6D.UK
EHPT30X-MED EHPT30X-MED.UK
EHPT30X-YM9ED EHPT30X-YM9ED.UK
ERPT30X-VM2ED ERPT30X-VM2ED.UK

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OCH729
SAFETY PRECAUTION
2
WARNING
●
●
●
●
INSTALLATION MANUAL
If the cylinder unit (hydrobox) has already been connected to the power supply, ensure circuit breaker is off before carrying out
electrical work.
If the 2 zone kit is installed incorrectly or modified after installation by the user, water may leak or 2 zone kit may fall from the
cylinder unit or wall.
All installation should be performed by a qualified technician according to local regulations and the instructions given in this
manual.
Connections must be made securely and without tension on the terminals.
CAUTION
●
●
●
●
●
●
●
●
●The 2 zone kit must be installed by 2 or more people.
All exposed water pipework should be insulated to prevent unnecessary heat loss and condensation.
To also use the 2 zone kit in cooling mode, securely apply heat-insulation to draining pipework. If heat-insulation is
inadequate, condensation could occur on the surface of pipes and dew could drop on the floor or important goods.
To prevent dirty water from draining onto the floor next to the cylinder unit or under the hydrobox, please connect appropriate
discharge pipework from the 2 zone kit to its disposal location.
Secure 2 zone kit to prevent it from falling.
Do not hold piping or drain socket when moving the 2 zone kit.
Avoid the connection of piping or drain socket from damage. Otherwise, it may cause water leakage.
To prevent incorrect installation, please connect the flexible hose at the bend radius of 150 mm or more.
The water flow rate between the cylinder unit (hydrobox) and the 2 zone kit must be greater than the total flow rate of Zone1
and Zone2. Otherwise, Zone1 and Zone2 may not be heated properly.
● This 2 zone kit MUST be used with the cylinder unit (hydrobox) except for E*SE models.
●
Before starting installation, read the following description together with the installation manual included with the cylinder unit (hydrobox)
and 2 zone kit.
● Please read it carefully and observe fully the following safety precautions.
Precaution that must be observed to prevent injuries or death.
WARNING
After installation, carry out a test run to ensure correct operation, then explain operation method and safety precautions to the
end user.
Tell your customers when they give or sell this machine to any other person include installation manual.
●
Incorrect handling could lead to injury or damage to house and household articles.
CAUTION

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OCH729
SPECIFICATIONS
3
Model name PAC-TZ02-E
Dimension (W × H × D) mm 265 × 383 × 383
Weight kg 17
Power supply 230 V/single phase/50Hz from Cylinder unit (Hydrobox)
Sound pressure level dB(A) 28
Sound power level dB(A) 40
Pump2, 3 Max. 52 W/0.52 A
Max. head 7.0 m *1
Mixing valve W 5
Running time 90° 120 s
Water ow rate range Depend on outdoor unit
Note:
● Max. ow rate is 36.9 L/min. If the ow rate exceeds 36.9 L/min, pipes would be eroded.
●
The water ow rate between the cylinder unit (hydrobox) and the 2 zone kit must be greater than the total ow rate of Zone1
and Zone2.
*1
Refer to the graph below and add any pumps if necessary.
<PP: Proportional pressure>
0
10
20
30
40
50
60
70
80
0 01 02 04 05 6 0
External static pressure [kPa]
30
Flow rate [L/min]
PP1
PP2
PP3
<CP: Constant pressure>
<CC: Constant curve>
CP1
CP2
CP3
0 01 02 04 05 706030
Flow rate [L/min]
0
10
20
30
40
50
60
70
80
External static pressure [kPa]
0
10
20
30
40
50
60
70
80
0 01 02 04 05 6 0
External static pressure [kPa]
30
Flow rate [L/min]
CC3
CC2
CC max.
CC1
The head (pressure) is reduced at falling heat demand and
increased at rising heat demand.
PP1: lowest proportional pressure curve
PP2: intermediate proportional pressure curve
PP3: highest proportional pressure curve
PP Auto Adapt: highest to lowest proportional pressure
curve
The Auto Adapt function enables the circulator to adjust the
pump performance automatically to the size of the system
or the variations in load over time.
The head (pressure) is kept constant, irrespective of the
heat demand.
CP1: lowest constant pressure curve
CP2: intermediate constant pressure curve
CP3: highest constant pressure curve
CP Auto Adapt: highest to lowest constant pressure curve
The Auto Adapt function enables the circulator to adjust the
pump performance automatically to the size of the system
or the variations in load over time.
The circulator runs on a constant curve.

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OCH729
PARTS NAMES AND FUNCTIONS
4
4-1. Component parts
4-2. Water circuit and system gure
Cylinder unit
(Hydrobox)
2 zone kit
<Zone1>
Radiator
<Zone2>
Floor heating
Pump3
THW6
THW7
THW8
Pump2
THW9
Air
vent
Air
vent
Water flow direction
Mixing
valve
PAC-TZ02-E
Pump3 Pump2
Mixing valve
Thermistor
Manual air vent
Reactor box
Thermistor
Earth terminal

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OCH729
OUTLINES AND DIMENSIONS
5
Unit: mm
Legend
AFrom Cylinder unit (Hydrobox)
B To Cylinder unit (Hydrobox)
C From Zone1
D To Zone1
E From Zone2
F To Zone2
PAC-TZ02-E
G1 connection
B
AC D
F E
Drain socket
(Size: Φ18.5)
BAC
D
F
E

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OCH729
6WIRING DIAGRAM
DIP Switch settings of the cylinder unit (hydrobox)
Setting the following DIP switches are necessary for 2 zone control. (See the installation manual of the cylinder unit (hydrobox)
for more information.)
DIP switch Function OFF ON Setting when using 2 zone kit
SW2-6 Mixing tank WITHOUT Mixing tank WITH Mixing tank ON
SW2-7 2-zone temperature control Inactive Active * ON
* Active only when SW3-6 is set to OFF.
PAC-TZ02-E

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OCH729
TROUBLESHOOTING
7
7-1. Troubleshooting
<Summary of self diagnosis based on error codes and service procedures>
Present and past error codes are logged and displayed on the main remote controller or control board of the outdoor unit.
If error codes are displayed, refer to the service manual of the cylinder unit (hydrobox) to solve the problem.
7-2. Test Run
Before a test run
• After installation of outdoor unit, pipework and electrical wiring, recheck that there is no water leakage, loosened connections or miswiring.
• Measure impedance between the ground and the power supply terminal block (L,N) on the outdoor and indoor units with suitable (500 V) ohmmeter. Resistance
should be ≥ 1.0 MΩ .
• Read the Installation and Operation Manuals fully especially the safety requirements before carrying out any test runs.
7-3. Malfunction diagnosis method by main remote controller
If a malfunction occurs during start up or operation, the error code screen may be displayed on the main remote controller.
The error code screen shows the following; code, unit, ref. address, and telephone number of installer (only if previously entered by the installer).
Please note in the case of some malfunctions that an error code is not generated, please refer to the service manual for the cylinder unit (hydrobox) for more details.
To reset
1. To reset the main remote controller press F4 button (Reset).
2. Then press F3 (Yes) to conrm.

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7-4. Checking component parts' function
Part Name Check Points
Water circulation pump 2/3
L N
M
1~
Mixing valve
CCW (Open)
Black
CW (Close)
Brown
N
Blue
M
1~
(1) Check if wirings are correct.
TBO.2-1: Brown
TBO.2-2: Blue
TBO.2-3: Black
(2) Remove the motor part from the mixing valve and check if it functions prop-
erly as follows:
• The motor dial rotates in a CW direction when 230 V is applied between
brown and blue.
• The motor dial rotates in a CCW direction when 230 V is applied between
black and blue.
(3) If the motor functions properly, the valve may be locked by some cause: Re-
move the valve to check for clogging inside.
Thermistors Disconnect the connector then measure the resistance with a tester.
(At ambient temperatures of 10–30°C.)
Thermistor Normal Abnormal
THW6
4.3–9.5 kΩ Open or short
THW7
THW8
THW9
<CC: Constant curve> The circulator runs on a constant curve.
0
10
20
30
40
50
-20 -10 0 10 20 30 40 50
Temperature (:)
Resistance (k")
<Thermistor Characteristics Charts>
• Zone1 ow water temperature thermistor (THW6)
• Zone1 return water temperature thermistor (THW7)
• Zone2 ow water temperature thermistor (THW8)
• Zone2 return water temperature thermistor (THW9)
0°C 15 kΩ
10°C 9.6 kΩ
20°C 6.3 kΩ
25°C 5.2 kΩ
30°C 4.3 kΩ
40°C 3.0 kΩ
Thermistor R0 = 15 kΩ± 3 %
B constant = 3480 ± 2 %
Rt = 15exp {3480 ( 273+t – 273 )}
1
1
0
10
20
30
40
50
60
70
80
0 01 02 04 05 6 0
External static pressure [kPa]
30
Flow rate [L/min]
CC3
CC2
CC max.
CC1

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OCH729
8DISASSEMBLY PROCEDURE
<Preparation for the repair service>
● Prepare the proper tools.
● Prepare the proper protectors.
● Provide adequate ventilation.
● After stopping the operation of the cylinder unit (hydrobox) and outdoor unit, turn off all the power-supply breaker.
● Discharge the condenser before the work involving the electric parts.
● Allow parts to cool.
● Do not expose the electric parts to water.
● When replacing or servicing water circuit parts, drain system first.
Check individual illustrations and positions of the parts by referring to the parts catalog.
Some lead wires and pipes are bundled with Bands. Cut the bands to undo the fastened pipes and lead wires if necessary.
When removing the parts associated with water pipe work, drain the 2 zone kit. Refer to "Draining the cylinder unit" or Draining
the hydrobox" on page 14.)
When draining the 2 zone kit, keep water from splashing on the internal parts (mainly electric parts and insulations).
PAC-TZ02-E : Indicates the visible parts in the photos/gures.
: Indicates the invisible parts in the photos/gures.
DISASSEMBLY PROCEDURE PHOTOS/ FIGURES
1. How to remove the front panel
(1) Remove the 6 screws fixing the front panel (Photo 1-1
and Photo 1-2).
(2) Remove the front panel.
Photo 1-1
Photo 1-2
2. How to remove the mixing valve motor/mixing valve body
<Mixing valve motor>
(1) Remove the front panel (Refer to Procedure 1).
(2)
Disconnect the TBO.2 1-3 from the controller board of the
cylinder unit (hydrobox) (Photo 5-1).
(3) Release the lead wires from the following fixtures:
(Photo 2-1 and 5-1)
• 2 cable straps on the 2 zone kit
• Cable straps and cable clamps in the control box of
the cylinder unit (hydrobox)
• Cable straps on the cylinder unit (hydrobox)
(4) Hold the motor of the mixing valve and pull hard to
remove it from the valve (Photo 2-2).
<
Mixing valve body>
(5) Loosen the 3 G1" nuts using the 2 spanners (Photo 2-3).
Note: When reinstalling the G1" nuts, use new G1" gaskets.
Photo 2-1
Photo 2-3
Photo 2-2
Front panel
Screws
Mixing valve motor
Screws
Mixing valve body
Cable straps
Nut ( G1" )
Gasket (G1")
Nut ( G1" )
Gasket (G1")
Nut ( G1" )
Gasket (G1")

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DISASSEMBLY PROCEDURE PHOTOS/ FIGURES
3. How to remove the water pump 2/pump 3
(1) Remove the front panel (Refer to Procedure 1).
(2) Remove the mixing valve motor (Refer to Procedure 2).
(3) Disconnect the connector between the pump lead wire
and the relay connector (Photo 3-1).
(4) Loosen the 2 G1" nuts of the removing water pump
(Photo 3-2).
Note: •
When reinstalling the G1" nuts, use new G1" gaskets.
• Install the water pump in the direction that the lead
wire comes to the bottom panel side (Photo 3-1).
Photo 3-1
Photo 3-2
4. How to remove the reactor 1 / reactor 2
(1) Remove the front panel (Refer to Procedure 1).
(2) Disconnect the connector between the reactor and the
relay connector (Photo 4-1).
(3)
Release the 2 cable straps and cut the band (Photo 4-1).
(4) Remove the 6 screws fixing the pipe stay to remove the
2 saddle bands and the rubber tubes (Photo 4-2).
(5) Tilt the pipe stay toward the mixing valve, pull to the
side to remove (Photo 4-3).
(6) Remove the 2 screws for the reactor box (Photo 4-4).
(7) Remove the 4 screws for the reactors (Photo 4-5).
Photo 4-1
Photo 4-3
Photo 4-5
Photo 4-2
Photo 4-4
Pump connectors (3 pin) Bottom panel
Nut ( G1" ) Gasket (G1")
Nut ( G1" )
Gasket (G1")
Nut ( G1" )
Gasket (G1")
Pump 3
Pump 2
Screws
Screws
Reactor box
Reactor
connectors
Cable straps
Band
Pipe stay
Screws
Reactors
Saddle bands and rubber tubes
Nut ( G1" )
Gasket (G1")

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OCH729
DISASSEMBLY PROCEDURE PHOTOS/ FIGURES
5. How to remove the flow water temp. & return water
temp. thermistor (THW6, THW7, THW8, THW9)
(1) Remove the front panel (Refer to Procedure 1).
(2) Disconnect the removing thermistor connector from the
controller board of the cylinder unit (hydrobox) (Photo
5-1).
Thermistor Connecting part of the controller board
THW6 TBI.5 7-8
THW7 TBI.5 5-6
THW8 TBI.5 3-4
THW9 TBI.5 1-2
(3) Release the lead wires from the following fixtures:
(Photo 4-1 and 5-1)
• Cable straps on the 2 zone kit
• Cable straps and cable clamps in the control box of
the cylinder unit (hydrobox)
• Cable straps on the cylinder unit (hydrobox)
(4) Remove the thermistor from the holder (Photo 5-2).
Photo 5-1
Photo 5-2
6. How to remove the air vent (manual)
(1) Remove the front panel (Refer to Procedure 1).
(2) Remove the air vent (manual) by turning the air vent
(manual). (Photo 6)
Photo 6
TBO.2 1-3
Cable
clamps
Thermistor connectors
Air vent (manual)
Thermistor
(THW8)
Thermistor
(THW6)
Thermistor
(THW9)
Thermistor
(THW7)
Cable strap

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OCH729
DISASSEMBLY PROCEDURE PHOTOS/ FIGURES
7. How to detach and attach the quick connection
Refer to the following steps when detaching and attaching
the quick connection.
(1) Remove the clip (Photos 7-1 and 7-2).
(2) Separate the connected parts to remove the O-ring
(Photo 7-3).
• Do not reuse the removed O-ring.
• Wipe off if dirt or foreign matters are found on the seal-
ing surface where the O-ring touches.
(3)
Apply grease on the O-ring using a plastic bag, etc.
(Photo 7-4)
(4) Attach the O-ring to the male part of quick connection.
(Photo 7-5)
• Keep the O-ring free from dirt or foreign matters.
(5)
Connect the male and female parts of the quick connec-
tion. (Photo 7-6)
(6) Attach the clip. (Photo 7-7)
• Ensure to attach the wider diameter of the clip to the
female side. Failure to do so it may cause water leak at
the connected part. (Photo 7-8) (For the same diame-
ter quick connection, following this note is not neces-
sary.)
Photo 7-1
Photo 7-2
O-ring
Plastic
bag
Female Male
O-ring
Photo 7-3 Photo 7-4 Photo 7-5
Photo 7-6 Photo 7-7 Photo 7-8
Clip
Clip
Gap
Clip

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OCH729
Notes on replacing the parts
When reinstalling the parts that are listed below, observe the tightening torques in accordance with Table 8 - 1 .
Always use a new O
- ring or gasket.
Table 8-1
Size
[inch]
Recommended tightening torque
[Nm]
Gasket G1 42 ± 2
Attached packing Air vent (manual) 0.25 ± 0.05
Draining the cylinder unit
WARNING: DRAINED WATER MAY BE VERY HOT
1. Before attempting to drain the cylinder unit isolate from the electrical supply to prevent the immersion and booster heaters burning out.
2. Isolate cold water feed to DHW tank.
3. Attach a hose to the DHW tank drain cock. The hose should be able to withstand heat as the draining water could be very hot. The hose should drain to a place
lower than the DHW tank bottom to encourage siphoning.
Open a hot water tap to start draining without a vacuum.
4. When the DHW tank is drained close drain cock and hot tap.
5. Attach hose to water circuit drain cock. The hose should be able to withstand heat as the draining water could be very hot. The hose should drain to a place lower
than the booster heater drain cock to encourage siphoning. Open the pump valve and the strainer valve.
6. Water remains in the strainer still after the cylinder unit was drained.
Drain the strainer by removing the strainer cover.
Draining the hydrobox
WARNING: DRAINED WATER MAY BE VERY HOT
1. Before attempting to drain the hydrobox isolate from the electrical supply to prevent booster heater burning out.
2. Isolate hydrobox from primary water circuit and drain water from hydrobox. Use a suitable heat resistant hose to assist in these operations.
3. Drain any remaining water from booster heater using tted drain cock and hose, and the drain valve on the primary circuit to safely drain the unit.
4. After the hydrobox is drained, water remains in the following component parts. Drain water completely by checking the inside of the parts.
• Strainer (Remove the strainer cover.)
• Pressure relief valve (Operate the valve.)

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HEAD OFFICE: TOKYO BUILDING, 2-7-3, MARUNOUCHI, CHIYODA-KU, TOKYO 100-8310, JAPAN
Copyright 2019 MITSUBISHI ELECTRIC CORPORATION
Published: Nov. 2019 No. OCH729
Made in Japan Specifications are subject to change without notice.