MTA NGSi 05, Technical Manual, Page: 16 / 58

TECHNICAL MANUAL
Chapter 8
- Start-up
NGSi 05÷15
14
ENGLISH
EN
The data in this manual are not binding and they can be modified by the manufacturer without notice. Reproduction of this manual is strictly prohibited
C
HAPTER
8
S
TART
-
UP
Before start-up:
• Check that system diagrams and manuals for the unit installed are available.
• Check that electrical and water system diagrams of the system to which the unit is connected are available.
• Check that the water circuit stop taps are turned on.
• Check that the water system has been filled and pressurised and the air has been vented.
• Check that all the water system connections have been made correctly and all the instructions on the decals have been
followed.
• Check that arrangements have been made for the drainage of condensate.
• Check the electrical connection and that all the terminals are secure.
• Check that the electrical connections have been made in accordance with the relevant standards, including the ground
connection.
• The voltage must be as stated on the unit nameplate.
• Check that the power supply voltage is within the tolerance limits (±10%).
• Check that the compressor heaters are receiving power correctly.
• Check that there are no gas leaks.
• Before switching on the system, check that all the enclosing panels are in place and secured with the screws provided.
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HAPTER
9
U
SER
- C
ONTROL
I
NTERFACE
onoff digital input remote on/off input (closed=unit on / open=unit off)
0-10V+ analogue input (ST10) 0-10V (+) signal input for setpoint modification
0-10V- analogue input (ST10) 0-10V (-) signal input for setpoint modification
WARNING:
The unit must be connected to the electrical mains and set in STANDBY mode (powered up) by turning on the master switch
at least 12 hours before start-up, to allow the heater to warm up the compressor crankcase as required (the heaters are
automatically powered up when the master switch is on). The heaters are operating correctly if the compressor crankcase
temperature has risen to 10÷15°C above room temperature within a few minutes.
WARNING:
Never stop the unit temporarily by turning off the master switch; this must only be done to disconnect the unit from the power
supply for lengthy stoppages (e.g. seasonal lay-offs, etc.). When the power supply is disconnected the crankcase heaters no
longer receive power, leading to the risk of a compressor breakdown when the unit is started up.
WARNING:
Do not modify the electrical connections to the unit; otherwise, warranty cover is forfeited at once.
WARNING:
Summer/winter operating mode must be selected at the start of the relative season. Frequent switching back and forth
between these modes is not recommended, as it may damage the compressors.
WARNING:
When the unit is installed and commissioned, check that it operates correct in both heating and cooling modes.
Selects the operating mode and resets alarms which can be rearmed manually. The sequence at consecutive
pressures on the key is:
off Æ cool Æ heat Æ off
If domestic hot water is enabled, the sequence is:
off Æ cool Æ cool+san Æ heat Æ heat+san Æ off
During parameter setting, it moves BACK one level.
Accesses the parameter setting menu, allowing setting of the summer, winter and domestic hot water setpoints.
Terminal Type Connection