6
Service and Maintenance
Annual Maintenance
It is essential that the hydrobox is serviced at least once a year by a qualified individual. Any required parts MUST be purchased from Mitsubishi Electric (safety matter).
NEVER bypass safety devices or operate the unit without them being fully operational.
Note
▪ Within the first couple of months of installation, remove and clean the hydrobox's strainer plus any additional filter items that are fitted external to the
hydrobox. This is especially important when installing on an old/existing pipe work system.
▪ The PRV valve (No. 11 on Figure 3.3 and 3.4) should be checked annually by turning the knob manually so that the medium is discharged, thus cleaning
the seal seat.
In addition to annual servicing it is necessary to replace or inspect some parts after a certain period of system operation. Please see tables below for detailed instructions.
Replacement and inspection of parts should always be done by a competent person with relevant training and qualifications.
Parts which require regular replacement
Parts
Pressure relief valve (3 bar)
Air vent (Auto/Manual)
Manometer
Engineers Forms
Should settings be changed from default, please enter and record new setting in 'Field Setting' column. This will ease resetting in the future should the system use change
or the circuit board need to be replaced.
Commissioning/Field settings record sheet
Main remote controller screen
Main
Option
Setting
DHW *13
Legionella prevention *13
Heating/ Cooling *12
Compensation
Hi flow temp. set
curve
point
Lo flow temp. set
point
Adjust
Holiday
Replace every
Possible failures
6 years
Water leakage
Zone1 heating room temp.
Zone2 heating room temp. *14
Zone1 heating flow temp.
Zone2 heating flow temp. *1
Zone1 cooling flow temp. *12
Zone2 cooling flow temp. *12
Zone1 heating compensation curve
Zone2 heating compensation curve *1
Holiday mode
Forced DHW operation
DHW
Heating/Cooling
Energy monitor
Operation mode
DHW max. temp.
DHW temp. drop
DHW max. operation time
DHW mode restriction
DHW recharge
Active
Hot water temp.
Frequency
Start time
Max. operation time
Duration of maximum temp.
Zone1 operation mode
Zone2 operation mode *1
Zone1 outdoor ambient temp.
Zone1 flow temp.
Zone2 outdoor ambient temp. *1
Zone2 flow temp. *1
Zone1 outdoor ambient temp.
Zone1 flow temp.
Zone2 outdoor ambient temp. *1
Zone2 flow temp. *1
Zone1 outdoor ambient temp.
Zone1 flow temp.
Zone2 outdoor ambient temp. *1
Zone2 flow temp. *1
DHW *13
Heating/ Cooling *12
Zone1 heating room temp.
Zone2 heating room temp. *14
Zone1 heating flow temp.
Zone2 heating flow temp. *1
Zone1 cooling flow temp. *12
Zone2 cooling flow temp. *12
Parts which require regular inspection
Parts
Check every
Pressure relief valve (3 bar)
1 year
Temperature and pressure
(turning the knob
relief valve
manually)
Immersion heater
2 years
Water circulation pump
20,000 hrs (3 years)
(Primary circuit)
Parts which must NOT be re-used when servicing
* O-ring
* Gasket
Notes:
• Always replace the gasket for pump with a new one at each regular main-
tenance (every 20,000 hours of use or every 3 years).
• No need to inspect pressure relief valve (5 bar) because it does not con-
tact with water unless 3 bar PRV is broken.
Parameters
10°C - 30°C
10°C - 30°C
20°C - 60°C
20°C - 60°C
5°C - 25°C
5°C - 25°C
−9°C - + 9°C
−9°C - + 9°C
Active/Non active/Set time
On/Off
On/Off/Timer
On/Off/Timer
Consumed electrical energy/Delivered energy
Normal/Eco *16
40°C - 60°C *2
5°C - 30°C
30 - 120 min
30 - 120 min
Large/Standard
Yes/No
60°C - 70°C *2
1 - 30 days
00.00 - 23.00
1 - 5 hours
1 - 120 min
Heating room temp./ Heating flow temp./ Heating
compensation curve/ Cooling flow temp.
Heating room temp./ Heating flow temp./ Heating
compensation curve/ Cooling flow temp.
−30°C - +33°C *3
20°C - 60°C
−30°C - +33°C *3
20°C - 60°C
−28°C - +35°C *4
20°C - 60°C
−28°C - +35°C *4
20°C - 60°C
−29°C - +34°C *5
20°C - 60°C
−29°C - +34°C *5
20°C - 60°C
Active/Non active
Active/Non active
10°C - 30°C
10°C - 30°C
20°C - 60°C
20°C - 60°C
5°C - 25°C
5°C - 25°C
Possible failures
PRV would be fixed and
expansion vessel would
burst
Earth leakage causing
circuit breaker to activate
(Heater is always OFF)
Water circulation pump
failure
Default setting
Field setting Notes
20°C
20°C
45°C
35°C
15°C
20°C
0°C
0°C
—
—
On
On
—
Normal
50°C
10°C
60 min
30 min
Large *19
Yes
65°C
15 days
03.00
3 hours
30 min
Room temp.
Compensation curve
−15°C
50°C
−15°C
40°C
35°C
25°C
35°C
25°C
—
—
—
—
Non active
Active
15°C
15°C
35°C
25°C
25°C
25°C
(Continued to next page.)
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