Lennox ADNOVA THX 045 Assembly instructions

www.lennoxemea.com
INSTALLATION, OPERATING
AND MAINTENANCE
WALL MOUNTED PACKAGED
INDOOR UNIT
@DNOVA
THX
4 - 15 kW ADNOVA-THX_R410A-
IOM-1506-E

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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
3 Installation 10
4Evacuation and Charging Operations 10
4.1 Introduction 10
4.2 Vacuum and charging machine 10
4.3 Evacuating a circuit “contaminated” with refrigerant 11
4.4 Charging positions (single point) 11
5Electrical Connections 12
5.1 Generalities 12
6Machine Functional Schemes 13
7Starting Up 14
7.1 Preliminary checks 14
7.2 Starting up instructions (for THX/D packaged air---conditioning units) 14
8Setting Operating Parameters 17
8.1 Generalities 17
8.2 Maximum pressure switch 17
8.3 Minimum pressure switch 17
9Maintenance 18
9.1 Warnings 18
9.2 Generalities 18
9.3 General inspection 19
9.4 Inspecting the air filter (THX) 19
9.5 Inspecting the air filter (THXD) 20
9.6 Inspecting the damper/motor (THXD) 20
9.7 Inspecting the damper/motor (THX) 22
9.8 Fixing of cables 22
9.9 Inspection of the compressor section 23
9.10 Inspection the sight glass and the filter drier 23
9.11 Repairing the cooling circuit 24
9.12 Tightness test 24
9.13 Hard vacuum and drying of cooling circuit 24
9.14 Recharging with refrigerant R410A 25
9.15 Environmental protection 25
10 Troubleshooting 26
11 Dimensional drawing 27

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1 GENERAL DESCRIPTION
THX/D “Lennox Wall-mounted Telecom units” are air conditioners for low- and medium-powered telephone
exchanges. They are designed to be mounted on an outside wall of the shelter.THX 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 THX/D units have a galvanised sheet steel supporting base, coated with epoxy polyester powder paint
oven cured at 180°C, and enclosing panels made of aluminium and magnesium alloy 5005 (Peraluman) or,
on request, painted galvanised sheet steel (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
THX/D 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 limits
Modello
THX
045
THXD
045
THX
056
THXD
056
THX
073
THXD
073
THX
090
THXD
090
THX
105
THXD
105
THX
120
THXD
120
THX
145
THXD
145
THX
230
THX 290
Alimentazione
elettrica
230Vac 10%
24Vdc 16% / 48Vdc 16% 400Vac 10% / 3Ph + N / 50Hz
24Vdc 16% / 48Vdc 16%
Condizioni
ambientali
esterne min. - 20 °C
Condizioni
ambientali
esterne max. 48,0 °C 46,5 °C 45,0 °C 47,0 °C 45,0 °C 46,0 °C 48,0 °C
48,0 °C 46,0 °C
Condizioni
ambientali
interne min. /
Umidità
19 °C / 30 % U.R.
Condizioni
ambientali
interne max. /
Umidità
35 °C / 50 % U.R.
Condizioni di
immagazzinamento -10 °C / 90 % U.R.
+55 °C / 90 % U.R.

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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 THX
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]

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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 Wall mounted unit
THX0230-290

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3 Installation
The THX/D package air-conditioning unit is suitable for all environments except aggressive ones. Do not
place any obstacles near the units and make sure that the air flow is not impeded by obstacles and/or
situations causing back suction (see Fig.3).
Fig. 3 Service Area
A (mm)
B (mm)
C (mm)
D (mm)
Min. 400
Min. 200
Min. 400
Min. 2000
The following steps should be carried out to ensure proper installation (see Fig. 4):

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•Apply a vibration-damping rubber lining between the unit and wall
•Position the unit on the wall, fitting the air outlet and intake flanges correctly into place; use M8 screws
secured by suitable anchors to fasten the unit.
•carefully seal the entire perimeter of the unit on the exterior wall of the shelter and the air intake and
outlet flanges on the inside.
•In order to obtain stable indoor conditions, make sure that the shelter interior is insulated from the
outside; any openings should be sealed closed
Position the air outlets (with a double row of vertical and horizontal fins) and intakes (with a single row of
horizontal fins) inside the shelter and fix them in place with self-tapping screws. Refer to the installation
drawings provided for the exact indications.
Fig. 4 Shelter installation
The recommended sizes for the power cables and emergency line are indicated in the attached electrical
scheme.
Unità HTW Uni tà HTWD

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4 Evacuation and Charging Operations
This type of work must be carried out by qualified personnel only trained to do their job
in accordance with current laws and regulations.
4.1 Introduction
The simultaneous presence of liquid and vapourmakes it necessary for both to be in a state of saturation
(Gibbs law), as shown
in Fig. 5. In conditions of thermal equilibrium, the pressure in the tank corresponds to the T of the
surrounding environment;
a withdrawal of refrigerant charge will cause pressure drops, which will be associated with:
•with drawal of refrigerant charge pressure drop in tank
•pressure drop in tank: T drop change of state
•T drop change of state: evaporation of part of the liquid, causing the liquid itself to
cool
•cooling of liquid: thermal exchange with ambient air, further evaporation of
remaining liquid;the original pressure is restored in the tank
after a certain amount of time
Fig. 5 Diagramma legge di Gibbs
4.2 Vacuum and charging machine
Vacuum cycle
In general it is preferable to apply a “long” rather than “hard” vacuum: reaching low pressures too abruptly
may in fact cause any trapped humidity to evaporate instantaneously, thereby freezing part of it.
Fig. 6 Vacuum cycle diagram
The Fig. 6 represents a vacuum cycle and an optimal subsequent pressure rise for the refrigeration devices
we manufacture. As a rule, if there is suspicion of an extensive presence of humidity throughout the circuit
or system as a whole, the vacuum must be “broken” with anhydrous nitrogen and then the steps must be

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repeated as described; this operation facilitates the removal of trapped and/or frozen humidity during the
evacuation process.
4.3 Evacuating a circuit “contaminated” with refrigerant
The first step is to remove the refrigerant from the circuit using a specific machine with a dry compressor
for recovering the refrigerant. Refrigerants all tend to dissolve in oil (compressor sump) in percentages that
are directly proportional to increases in pressure and decreases in the T of the oil itself --- Charles’ Law ---
(see Fig. 7).
Fig. 7 Charles’ law diagram
The release of refrigerant tends to cool the oil and thus actually serves to oppose the release itself: for this
reason, it is advisable to switch on the crankcase heating elements, if available, during the evacuation
process. If a high % of refrigerant gets into contact with the Pirani gauge (vacuum sensor), it may “drug”
the sensitive element of the latter, rendering it inefficient 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
heating elements and avoid applying a vacuum until the circuit has been adequately purged of refrigerant:
the refrigerant may in fact solubilize in the oil of the vacuum pump, undermining its performance for
a long time (hours).
4.4 Charging positions (single point)
The best position for charging the air conditioners is the section between the thermostatic valve and the
evaporator; care should be taken to avoid fixing the thermostat bulb until the operation is complete: this is
important to ensure that the valve orifice remains open so as to allow the passage of refrigerant also
toward the condenser/receiver.
If possible, avoid the inflow of refrigerant into the compressor as this may cause excessive dilution of the
lubricant; in any case, first check the compatibility between the crankcase capacity and the required charge
volumes.

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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 earth wire using the earth 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.

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6 Machine Functional Schemes
Fig. 8 Machine functional schemes

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7 Starting Up
7.1 Preliminary checks
•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.
•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.
•Make sure there are no refrigerant leaks that may have been caused by accidental impacts during
transport and/or installation.
•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. 9 Diagramma legge di Charles
The diagram in Fig. 9 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.
7.2 Starting up instructions (for THX/D packaged air---conditioning units)
Electric connections and starting up
•Loosen the screws securing the cover of the electric compartment and open it.
•Introduce the power cable through the hole provided on the side of the unit (see Fig. 10) and secure it in
place with the cable holder.

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Fig. 10 Electrical cables inlet holes
Electrical power / UPS inlet
•Connect the power supply and earth wire to the terminals of the main switch.
•Put OFF switch “QF1” of the compressor so as to be sure it will not start running in the wrong direction in
the case of a phase sequence error.
•Switch on the power supply by turning the main switch (QS) to ON.
•After 60 seconds the compressor will start.
•Check the phase sequence relay situated in the middle of the electric control board to make sure the
phases are in the right sequence R---S---T; the green indicator light should go on: if it does not, disconnect
the power supply to the unit from the external distribution board, invert two phases and repeat the check.
IN NO CASE SHOULD YOU TAMPER WITH THE WIRING DOWNSTREAM FROM THE MAIN SWITCH
since this may alter the correct sequence of other devices.
•Check that there are no leaks on the refrigerant side.
•Put the compressor switch “QF1” back on.
•Close the electric compartment by replacing the cover.
Usage
•Always consult the USER manual and control system manual provided with the unit when under taking
maintenance and/or advanced Set-Up.
7.3 Starting operation
Before starting the unit, turn the main switch on, select the operating mode desired from the control panel
and press the ”ON” button on the control panel.
If the unit fails to start up, check if the service thermostat has been set according to the nominal
values provided.
You should not disconnect the unit from the power supply during periods when it is
inoperative but only when it is to be taken out of service for a prolonged period (e.g. at the
end of the season). To turn off the unit temporarily follow the directions provided in the
section 4.5.
Checks during operation

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•Check the phase sequence relay on the control board to verify whether the phases occur in the correct
sequence: if they do not, disconnect the unit from power supply and invert two phases of the incoming
three-pole cable.
Never attempt to modify internal electrical connections: any undue modifications will immediately
invalidate the warranty.
Checking the refrigerant level
•After a few hours of operation, check whether the liquid level indicator has a green ring: a yellow color
indicates the presence of humidity in the circuit. In such a case the circuit must be dehumidified by
qualified personnel.
•Large quantities of bubbles should not appear through the liquid level indicator. A constant passage of
numerous bubbles may indicate that the refrigerant level is low and needs to be topped up.
•Make sure the overheating of the cooling fluid is limited to between 5 and 8 °C: to this end:
1 ) read the temperature indicated by a contact thermometer placed on the compressor intake
pipe;
2 ) read the temperature indicated on the scale of a pressure gauge likewise connected to the
intake side; refer to the pressure gauge scale for the refrigerant R410A.The degree of overheating
is given by the difference between the temperatures thus determined.
•Make sure that the Sub-cooling of the cooling fluid is limited to between 3 and 5°C: to this end:
1 ) read the temperature indicated by a contact thermometer placed on the condenser outlet pipe;
2 ) read the temperature indicated on the scale of a pressure gauge connected to the liquid inlet at
the condenser outlet; refer to the pressure gauge scale for the refrigerant R410A, The degree of Sub-
cooling is given by the difference between the temperatures thus determined.
Warning: all THX/D units are charged with R410A. Any top-ups must be made using
the same type of refrigerant. This operation is to be considered extraordinary
maintenance work and must be performed by qualified personnel only.
Warning: the refrigerant R410A requires “POE” polyolester oil of the type and
viscosity indicated on the compressor rating plate. For no reason should oil of a
different type be introduced into the oil circuit.

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8 Setting Operating Parameters
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. 3 and Tab. 4.
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.
Tab. 3 Setting of control devices
Control device
Set point
Differential
Differential air pressure switch (outlet air flow)
Pa
50
30
Differential air pressure switch (dirty filter)
Pa
50
20
Tab. 4 Setting of control devices
Control device
Activation
Differential
Resetting
Maximum pressure switch
Bars-r
42.0
4
Manual
Minimum pressure switch
Bars-r
1.5
1.5
Automatic
Modulating condensation control device
Bars-r
20
6.5
Time lapse between two compressor starts
s
300
-
-
8.2 Maximum pressure switch
The high pressure switch stops the compressor when the outlet pressure exceeds the set value.
Warning: do not attempt to change the setting of the maximum pressure switch: Should the
latter fail to trip in the event of a pressure increase, the pressure relief valve will open.
The high pressure switch must be manually reset; this is possible only when the pressure falls below the
set differential (see Tab. 4).
8.3 Minimum pressure switch
The low pressure switch stops the compressor when the inlet pressure falls below the set value for more
than 1 seconds. The switch is automatically reset when the pressure rises above the set differential (see
Tab. 4).9

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9 Maintenance
The only operations to be performed by the user are to switch the unit On and Off. All other operations are
to be considered maintenance work and must thus be carried out by qualified personnel trained to do their
job in accordance with current laws and regulations.
9.1 Warnings
All the operations described in this chapter MUST ALWAYS BE PERFORMED BY
QUALIFIED PERSONNEL ONLY..
Before carrying out any work on the unit or accessing internal parts, make sure you
have disconnected it from the mains electricity supply.
The upper part and the outlet pipe of the compressor reach high temperatures. Be
especially careful when working in the surrounding area with the panels off.
Be especially careful when working in proximity to finned coils since the 0.11 mm thick
aluminum fins can cause superficial injuries due to cuts.
After completing maintenance jobs, always replace the panels enclosing the units and
secure them while fastening screws provided.
9.2 Generalities
To guarantee a constantly satisfactory performance over time, it is advisable to carry out routine
maintenance and checks as described in Tab. 5. The indications below are related to standard tear and
wear.
Tab. 5 Routine maintenance
Operation
Frequency
Check the efficiency of all the control and safety devices. Once a year
Check the terminals on the electric control board and compressor terminal boards to
ensure that they are securely tightened. The movable and fixed contacts of the circuit
breakers must be periodically cleaned and replaced whenever they show signs of
deterioration
Once a year
Check the refrigerant level by means of the liquid level indicator Every 6 mos.
Check the efficiency of the differential air pressure switch and dirty filter differential
pressure switch Every 6 mos.
Check the condition of the air filter and replace it if necessary Every 6 mos.
Check the humidity indicator (green=dry, yellow=humid) on the liquid level indicator; if the
indicator is not green as shown on the indicator sticker, replace the filter Every 6 mos.