Lennox @DNOVA THND 045 User manual

www.lennoxemea.com
INSTALLATION, OPERATING
AND MAINTENANCE
WALL MOUNTED PACKAGED
INDOOR UNIT
@DNOVA
THN
2,5 - 38 kW ADNOVA-THN_R410A-
IOM-1506-E

@DNOVA THN_R410A-IOM-1506-E - 1-
1General Description 2
1.1 Structure 2
1.2 Field of application 2
1.3 Cooling circuit 3
1.4 Installation warnings 4
2Inspection / Transport / Positioning 5
2.1 Inspection on receipt 5
2.2 Lifting and Transport 5
2.3 Unpacking 5
2.4 Positioning 5
3Installation 10
4Evacuation and Charging Operations 11
4.1 Introduction 11
4.2 Vacuum and charging machine 12
4.3 Evacuating a circuit “contaminated” with refrigerant 12
4.4 Charging positions (single point) 13
5Electrical Connections 13
5.1 Generalities 13
6Starting Up 14
6.1 Preliminary checks 14
6.2 Starting up instructions 15
7Setting Operating Parameters 17
7.1 Generalities 17
7.2 Maximum pressure switch 17
7.3 Minimum pressure switch 17
8Maintenance 18
8.1 Warnings 18
8.2 Generalities 18
8.3 Inspecting the air filter 19
8.4 Inspecting the damper servomotor 19
8.5 Repairing the cooling circuit 20
8.6 Tightness test 20
8.7 Hard vacuum and drying of cooling circuit 20
8.8 Recharging with refrigerant R410A 21
8.9 Environmental protection 21
9Troubleshooting 22

@DNOVA THN_R410A-IOM-1506-E - 2-
1 General Description
THND/U “Lennox Telecom units” are air conditioners for low- and medium-powered telephone exchanges.
They are designed to be mounted inside shelter.
THND/U air conditioners are direct expansion package units with an air-cooled condenser system. They
are distinguished by an innovative air circulation system which significantly enhances performance in all
operating conditions.
1.1 Structure
All THND/U units have a galvanised sheet steel supporting base, and enclosing panels made galvanised
sheet steel coated with epoxy polyester powder paint oven cured at 180°C (RALxxxx). The unit features
an exclusive design which, combined with a rational layout of components and extremely compact
dimensions, lends it an attractive appearance.
1.2 Field of application
THND/U units are to be used within the operating limits stated in this manual; failure to comply with said
limits will invalidate the warranties provided in the contract of sale (see Tab. 1)
Tab. 1 Operating limis
Model THND/U/X 045
THND/U/X
056
THND/U/X
073
THND/U/X
090
THND/U/X
105
THND/U/X
120
THND/U/X
150
Power supply 230Vac 10%
24Vdc 16% / 48Vdc 16%
400Vac 10% / 3Ph + N / 50Hz
24Vdc 16% / 48Vdc 16%
Minimum outdoor
temperature T - 20 °C
Maximum outdoor
temperature T
45 °C 45 °C 45 °C 47,0 °C 45,0 °C 46,0 °C 48,0 °C
Minimum indoor
temp./humidity
conditions 19 °C / 30 % U.R.
Maximum indoor
temp./humidity
conditions 35 °C / 50 % U.R.
Storage conditions -10 °C / 90 % U.R.
+55 °C / 90 % U.R.
Model THND/U/X
170
THND/U/X
180
THND/U/X
200
THND/U/X
220
THND/U/X
250
Power supply 400Vac 10% / 3Ph + N / 50Hz
Minimum outdoor
temperature T
- 20 °C
Maximum outdoor
temperature T
45 °C 46 ° 45 °C 46,0 °C 46,0 °C
Minimum indoor
temp./humidity conditions
19 °C / 30 % U.R.
Maximum indoor
temp./humidity conditions
35 °C / 50 % U.R.
Storage conditions -10 °C / 90 % U.R.
+55 °C / 90 % U.R.

@DNOVA THN_R410A-IOM-1506-E - 3-
1.3 Cooling circuit
The entire cooling circuit is built in the Lennox factory using only components of the finest quality brands
and processes conforming to the specifications of Directive 97/23 for brazing and testing.
Compressors: only scroll-type compressors of leading international manufacturers are used in the
THND/U/X units. Today scroll compressors represent the best solution in terms of reliability, efficiency
and MTBF.
Cooling components:
oMolecular mesh activated-alumina filter dryer
oFlow indicator with humidity indicator. Indications are provided directly on the sight glass.
oThermostatic valve with external equalization and integrated MOP function.
oHigh and low pressure switches
oSchrader valves for checks and/or maintenance
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 put off. All the remote controls use 24 V signals powered by an insulating
transformer situated on the electric control board. NOTE: the mechanical safety devices such as the
high pressure switch 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.
Control microprocessor: 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;
oSwitching on/off of compressor to maintain the temperature set point T inside the shelter
oAlarm management
High / low pressure
Dirty filters alarm
Air flow alarm
oAlarm signalling
oDisplay of operating parameters
oRS232, RS485 serial output management (optional)
oPhase sequence error [Not displayed by the mP, but prevents the compressor from starting up]
[see microprocessor control manual for further details, also in relation to particular customer
specifications]

@DNOVA THN_R410A-IOM-1506-E - 4-
Fig. 1 Basic cooling circuit
1
Compressor
2
Condenser
3
Thermostatic valve
4
Evaporator
5
Filter dryer
6
Sight glass
7
Low pressure switch
8
High pressure switch
9 Condensing pressure
probe
1.4 Installation warnings
General rules
•When installing or servicing the unit, you must strictly follow the rules provided in this manual, comply with
the directions on the units themselves and take all such precautions as are necessary.
•The fluids under pressure in the cooling circuit and the presence of electrical components may cause
hazardous situations during installation and maintenance work.
All work on the unit must be carried out by qualified personnel only, trained to do
their job in accordance with current laws and regulations
•Failure to comply with the rules provided in this manual or any modification made to the unit without prior
authorisation will result in the immediate invalidation of the warranty.
Warning: Before performing any kind of work on the unit, make sure it has been
disconnected from the power supply.
P
P
1
2
3
5
6
7
8
9
4
M
M

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2 Inspection / Transport / Positioning
2.1 Inspection on receipt
On receiving the unit, check that it is perfectly intact: the unit left the factory in perfect conditions;
immediately report any signs of damage to the carrier and note them on the Delivery Slip before signing it.
Lennox or its Agent must be promptly notified of the entity of the damage. The Customer must submit a
written report describing every significant sign of damage.
2.2 Lifting and Transport
While the unit is being unloaded and positioned, utmost care must be taken to avoid abrupt or violent
manoeuvres. The unit must be handled carefully and gently; avoid using machine components as
anchorages or holds and always keep it in an upright position. The unit should be lifted using the pallet it is
packed on; a transpallet or similar conveyance means should be used
Warning: In all lifting operations make sure that the unit is securely anchored in order to
prevent accidental falls or overturning.
2.3 Unpacking
The packing must be carefully removed to avoid the risk of damaging the unit. Different packing materials
are used: wood, cardboard, nylon etc. It is recommended to keep them separately and deliver them to
suitable waste disposal or recycling facilities in order to minimise their environmental impact.
2.4 Positioning
Bear in mind the following aspects when choosing the best site for installing the unit and the relative
connections:
•positioning and dimensions of the coupling flanges;
•location of power supply;
•solidity of the supporting wall;
It is recommended to first prepare holes in the wall for passing through the power cables, for the air intake
and outlet flanges and for the screw anchors that will secure the unit on the wall.
The dimensions of the air outlet/intake flanges and the positions of the holes for the screw anchors and
power cables are shown Fig. 2:

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Fig. 2 THND/X 045...170 (rear view)

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THND/X180-200 (rear view)
THNU220-250 (rear view)

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THNU090..120 (rear view)
THNU045..073 – 150-170