Lennox INNOV DM R Series, Application Manual

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INNOV@ ECFAN DMR -AGU-0912-E • 12 •
2 ) If a high % of refrigerant gets in contact with the Pirani gauge (vacuum sensor), it may “mislead” this sensitive
sensor and misinterpret the value for a certain period of time. For this reason, if no machine for recovering
refrigerant is available, it is nonetheless advisable to switch on the crankcase heater and to avoid full vacuum
before the circuit has been adequately purged of refrigerant. The refrigerant may in fact dissolve in the oil of the
vacuum pump, reducing its performance for a long time (hours).
4.4 Charging positions (single point
)
The best position to charge the unit is the section between the thermostatic valve and the evaporator. Take care to
avoid the fixing of the thermostat bulb until the operation is completed. It is important to ensure that the valve orifice
remains open in order to allow the passage of refrigerant also towards the condenser / liquid receiver.
If possible, avoid the charge of refrigerant into the suction line of the compressor as this may cause excessive dilution of
the lubricant.
In any case verify first the necessary volume of the crankcase and compare it with the required charge volumes.
5 Electrical Connections
5.1 Generalities
Before carrying out any job on electrical parts, make sure the power supply is disconnected.
Check that the mains electricity supply is compatible with the specifications (voltage, number of phases, frequency)
shown on the unit rating plate.
The power connection for single-phase loads is to be made with a three-pole cable and “N” wire at the centre of the star
(optional: power supply w/o neutral).
The size of the cable and line protections must conform to the specifications provided in the wiring
diagram.
The supply voltage may not undergo fluctuations exceeding ±5% and the unbalance between phases must always be
below 2%.
The above operating conditions must always be complied with: failure to ensure said conditions will
result in the immediate invalidation of the warranty.
The electrical connections must be made in accordance with the information shown in the wiring diagram provided with
the unit and with current and local regulations. An earth connection is
mandatory . The installer must connect the
earthing wire using the earthing terminal situated on the electric control board (yellow and green wire).
The power supply to the control circuit is taken from the power line through an insulating transformer situated on the
electric control board.
The control circuit is protected by suitable fuses or automatic breakers depending on the unit size.