Hitachi YUTAKI S COMBI Series Instruction Manual page 38

COMMISSIONING
7.2.1 Checking the unit
• Check external appearance of the unit to look for any
damage due to transportation or installation.
• Check that all the covers are totally closed.
• Check that the recommended service space is respected
(see "3.2 Service space"
operation manual).
• Check that the unit has been correctly installed and that the
mounting feet are correctly adjusted.
7.2.2 Electrical checking
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C A U T I O N
Do not operate the system until all the check points have been cleared:
• Check to ensure that the electrical resistance is more than 1 MΩ,
by measuring the resistance between ground and electrical parts
terminal. If not, do not operate the system until the electrical leakage
is found and repaired. Do not impress the voltage on the terminals for
transmission and sensors .
• Check to ensure that the switch on the main power source has been
ON for more than 12 hours, in order to give the oil heater time to warm
the compressor.
• In three-phase unit check phase sequence connection on terminal
board.
• Check the power supply voltage (±10% of the rated voltage).
• Check that field-supplied electrical components (main switches,
breakers, wires, conduit connectors and wire terminals) have been
properly selected according to the electrical specifications given in
this document, and check that the components comply with national
and local standards.
• Do not touch any electrical components for more than three minutes
after turning OFF the main switch.
• Check the dip switch settings of the indoor unit and the outdoor unit
are connected as shown in the corresponding chapter.
• Check to ensure the electrical wiring of the indoor unit and the outdoor
unit are connected as shown in the chapter.
• Check to ensure the external wiring is correctly fixed. To avoid
problems with vibrations, noises and cut out wires with the plates.
7.2.3 Hydraulic circuit checking (space heating
and DHW)
• Check that the circuit has been properly flushed and filled
with water and that the installation has been drained: the
pressure of the heating circuit must be 1.8 bar.
7.3 COMMISSIONING PROCEDURE
This procedure is valid regardless of what options are on the
module.
• When installation is complete and all necessary settings
(Dip-switches in PCBs and user controller configuration)
have been carried out, close the electrical box and place the
cabinet as shown in the manual.
• Make the start-up wizard configuration in the user controller.
• Make a test run as shown in item "7.4 Test run / air purge".
• After test run is completed, start the entire unit or the
selected circuit by pressing the OK button.
28 PMML0338B rev.6 - 12/2018
and the outdoor unit Installation and
• The pressure of the DHW circuit in the tank has to be lower
than 7 bars.
• Check that the water tank heating coil is completely filled.
• Check for any leakage in water cycle. Pay special attention
to the water piping connections.
• Make sure the system's internal water volume is correct.
• Make sure the DHW tank internal water volume is correct.
• Check that the hydraulic circuit's valves are fully open.
• Check to see that electrical heater is completely filled with
water by operating pressure of safety valve.
• Check to see that additional water pumps (WP2 or/and WP3)
are correctly connected to terminal board.
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C A U T I O N
• Operating the system with closed valves will damage the unit.
• Check to see that air purge valve is open and that the hydrau l ic circuit
is air purged. The installer is responsible of com p letely air purging the
installation.
• Check that the water pump of the space heating circuit works within
the pump operating range and that the water flow is over the pump's
minimum. If the water flow is under 12 litres/minute (6 litres/minute
for 2.0/2.5/3.0HP unit) (with flow switch tolerance), alarm will be
displayed on the unit.
• Remember that water connection must be accordance with local
regulations.
• Water quality must comply with EU directive 98/83 EC.
• Electrical heater operation when not completely filled with water will
damage the heater.
7.2.4 Checking the refrigerant circuit
• Check to ensure that the stop valves on the gas and liquid
lines are fully open.
• Check that the size of the piping and the refrigerant charge
comply with the applicable recommendations.
• Check the inside of the unit for refrigerant leakage. If there is
a refrigerant leak, call your dealer.
• Check outdoor unit commissioning procedure manual.
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Initial start-up at low outdoor ambient
temperatures
During commissioning and when water temperature is very
low, it is important for the water to be heated gradually.
Additional optional function can be used for starting at low water
temperature conditions: Screed drying function:
- The screed function is used exclusively for the process of
drying a newly applied screed to the floor heating system.
The process is based on EN-1264 par 4.
- When user activates screed function, the water set point
follows a predetermined schedule:
1 Water set point is kept constant at 25ºC for 3 days
2 Water set-point is set to the maximum Heating supply
temperature (but always limited to ≤ 55ºC) for 4 days.