The auxiliary digital inputs used for the remote control of the units (remote on/off, flow switch, pumps enable, etc.) must be voltage-free digital input, a

single digital input must be used for each unit (never make a parallel connection to more than one machine with a single enable).

• For further information please refer to the unit wiring diagram/external signal interface and the Interface Manual as guides. Moreover, for the remote ON/

OFF control of the unit from an external contact or from the serial protocol control, the following minimum delays must be complied with:

• Delays between 2 subsequent start-ups: 15 minutes

• Delay between shut-down and start-up: 3 minutes

• Furthermore, if the pump is not activated using the signal provided by the unit, its control has to be designed by making sure that it is operated for at

least 1 minute before starting the unit and it must be switched off 1 minute after the unit is shut down.

• Connect to the appropriate terminals of the control circuit:

o connect the calibrated flow switch to the specific terminals of the control circuit (if not included in the standard supply).

o connect the auxiliary pump contacts to the specific terminals of the control circuit (if present in the wiring diagram).

8.4

Obligatory checks and preparation for initial start-up

The hermetic seal of the refrigerant circuit is checked by Mehits. The hermetic seal test is carried out after final assembly of the machine at the production

plant. An additional test must be carried out before start-up, to check for refrigerant leaks caused by damage that might have occurred during transport

or installation.

Ensure that the installation complies with local regulations concerning pressurised components, electrical safety, electromagnetic compatibility and any

other possible standards.

Before starting up, power the unit for at least 2 hours to allow the compressor crankcase oil to warm up.

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Installation, use and maintenance manual - Original instructions

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