Lennox INNOV DM R Series Application Manual page 37

1.3 Cooling circuit
The entire refrigerating circuit is assembled in our production line including all pipe work and using
only primary brand for components. The workers involved in the welding and pipe work process are
qualified by a third part according CEE 97/23. The DX unit are prechargerd with dry nitrogen for "A",
"D" and with R410A refrigerant for "W", "F", "Q", "K" versions.
Compressors
On INNOV@ units only primary brand scroll compressors are installed. Scroll compressor represent
for CCAC units the best solution in terms of efficiency and reliability. The internal compression ratio is
very close to the typical operating condition of CCAC giving the maximum in terms of COPs and the
perfect balanced pressures at start up gives big advantages to the e_motor in terms of reliability,
mainly in this filed where frequent start up may be possible. All motors are thermally protected with an
internal sensors chain: in case of overload this sensor opens without giving contacts to the connection
box.
Cooling components
· Molecular mesh activated-alumina filter dryer.
· Flow indicator with humidity indicator (indications are provided directly on the sight glass).
· Thermostatic valve with external equalization and integrated MOP function or electic valve
(optional).
· High and low pressure switches.
· Schrader valves for checks and/or maintenance.
Electric control board
Electric control board: The electric control board is constructed and wired in accordance with
Directives 73/23/EEC and 89/336/EEC and related standards. The board may be accessed through a
door after the main switch has been turned off.All the remote controls use 24 V signals powered by an
insulating transformer situated on the electric control board.
· The mechanical safety devices such as the high pressure switched are of the kind that trigger
directly; their efficiency will not be affected by any faults occurring in the microprocessor control
circuit, in compliance with 97/23 PED.
Microprocessor control
The microprocessor built into the unit allows the different operating parameters to be controlled from a
set of pushbuttons situated on the electric control board:
· Switching On/Off of compressor(s) to maintain the temperature set point T inside the shelter.
· Alarm management : - High / Low pressure;
· Alarm signalling.
· Display of operating parameters.
· RS232, RS485 serial output management (optional).
· Phase sequence error (not displayed by the mP, but prevents the compressor from starting up)
(only DX).
See microprocessor control manual for further details, also in relation to particular customer
specifications.
INNOV@ ECFAN DHR -AGU-0912-E
- Dirty filters alarm (optional);
- Air flow alarm.
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