Technical data

Refrigerant Connections
Units are supplied with a nitrogen holding
charge.This should be relieved carefully via the
suction service connections and the liquid line
service connections.
The pipework can be brazed directly onto the
welding connections taking care to protect the unit
from excess heat which may cause distortion.
System Testing
All newly installed pipework must be pressure /
leak tested to national code requirements
(normally 1.1 x Design Working Pressure) then
fully evacuated before charging. Refer to the
section 5 for correct charging methods.
Incorrectly or badly designed and/or
installed pipework systems may
invalidate unit warranty
4.6 Electrical Supplies
Ensure that the power supply is off
before working on the electrical
system.
The unit must be provided with an
earth connection.
It is the installers responsibility to ensure
that all external wiring complies with
applicable safety regulations.
York is not responsible for injury or damage
of any kind resulting from failure to observe
these precautions.
The unit complies with CEI-IEC standards n.17/13
of 1980.
The electrical distribution system must be able to
supply all the unit power and the disconnect
switches and circuit breakers must be sized to
handle the unit starting current, refer to Section 9.
Supply and isolating devices shall be designed so
that the lines are fully independent. Magnetic
thermal differential breakers are recommended, to
prevent damage due to electrical phase loss.
Power supplies to the compressors are through
contactors controlled by the control panel. Each
motor is provided with an internal thermal overload
cut-out and external fuses.
Supply cables should be routed through the cable
entries on the unit and enter the electrical panel
through the hole.
4.7 Electrical Connections
The installation of the unit on the final site
must be carried out according to the
Machinery Safety Directive (CEE 89/392), (as
modified by Directive CEE 91/368, 93/44 and
93/68) to the Low Voltage Directive CEE 73/23,
to the Electromagnetic Interference Directive
CEE 89/336 and according to normal rules for
technical matters prescribed by country
regulations. Do not operate the unit before
having observed all the above. Supply lines
shall consist of insulated copper conductors
sized for maximum current draw.
Terminal connections should be made in
accordance with the connection diagram in this
manual and the diagram supplied with the unit.
Before connecting the supply lines, check
that the mains voltage is within the range
shown in the Electrical Data in Section 9.
For the 3 -phase power supply, also check that the
phase unbalance does not exceed 2%. The check
is performed by measuring the difference between
the voltage of each phase pair and the average
mains voltage during operation. The maximum
measured difference (unbalance) shall not exceed
2% of the average voltage.
If the unbalance is unacceptable, the electricity
supply company must be asked to correct the fault.
Supplying the unit with a line whose
unbalance exceeds the specified value
will automatically void the warranty.
4-4 035B40022-000