Lennox INNOV DM R Series, Инструкция по применению

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INNOV@ ECFAN DMR -AGU-0912-E • 14 •
7 Start-Up
7.1 Preliminary checks
D Check that the electrical connections have been made properly and that all the terminals are securely tightened.
This check should also be included in a periodic six-month inspection.
D Check that the voltage at the RST terminals is 400 V ± 5% and make sure the yellow indicator light of the phase
sequence relay is on. The phase sequence relay is positioned on the electric control board; if the sequence is not
duly observed, it will not enable the machine to start.
D
Make sure there are no refrigerant leaks that may have been caused by accidental impacts during transport and/or
installation.
D
Check the power supply to the crankcase heating elements, where present.
The heating elements must be turned on at least 12 hours before the unit is started.
They are automatically activated when the main switch is put on. Their function is to raise the T of the
oil in the sump and limit the quantity of refrigerant dissolved in it.
To verify whether the heating elements are working properly, check the lower part of the compressors: it should be
warm or in any case at a temperature 10 - 15 °C higher than the ambient temperature.
Fig. 10 Charles’ law diagram
The diagram above illustrates a specific property of gases (Charles’ Law), which are more soluble in liquids as the
pressure increases but less soluble as the temperature increases: if the oil in the sump is held at a constant pressure,
an increase in temperature will significantly reduce the amount of refrigerant dissolved in it, thus ensuring that the
desired lubricating function is maintained.
8 Operating Parameters Setting
8.1 Generalities
All the control devices are set and tested in the factory before the unit is dispatched. However, after the unit has been in
service for a reasonable period of time you can perform a check on the operating and safety devices.
The settings are shown in Tab. 6 and Tab. 7.
All servicing of the equipment is to be considered extraordinary maintenance and may be carried out
BY QUALIFIED TECHNICIANS ONLY: incorrect settings may cause serious damage to the unit and
injuries to persons.
The operating parameters and control system settings configurable by means of the microprocessor control are
password protected if they have a potential impact on the integrity of the unit.
Pressure
% R407C in oil
T Oil
T1
T2
T0