Lennox Adnova THS Series User manual

www.lennoxemea.com
INSTALLATION, OPERATING
AND MAINTENANCE
CEILING MOUNTED SPLIT UNIT
@DNOVA
THS
2,5 - 38 kW
ADNOVA-THS_R410A-
IOM-1304-E

@DNOVA THS_R410A-IOM-1304-E 1
Index
1General Description ............................................................................................................ 2
1.1 Structure ..........................................................................................................................................2
1.2 Field of application...........................................................................................................................2
1.3 Cooling circuit ..................................................................................................................................2
1.4 Installation warnings ........................................................................................................................5
2Inspection / Transport......................................................................................................... 6
2.1 Inspection on receipt........................................................................................................................6
2.2 Lifting and transport.........................................................................................................................6
2.3 Unpacking........................................................................................................................................6
3Installation........................................................................................................................... 7
3.1 THSI - Indoor unit positioning..........................................................................................................7
3.2 Free-cooling duct connections (optional).........................................................................................8
3.3 THSC - Outdoor unit positioning......................................................................................................8
3.4 Refrigerant connections...................................................................................................................9
3.5 Lines positioning..............................................................................................................................9
4THS - Evacuation and Charging Operations.................................................................... 10
4.1 Introductions ..................................................................................................................................10
4.2 Full vacuum and charge of the unit................................................................................................10
4.3 Evacuating a circuit “contaminated” with refrigerant......................................................................11
4.4 Charging positions (single point) ...................................................................................................11
5Electrical Connections...................................................................................................... 12
5.1 Generalities....................................................................................................................................12
6Starting Up......................................................................................................................... 14
6.1 Preliminary checks.........................................................................................................................14
6.2 Starting up for the first time............................................................................................................14
6.3 Start up ..........................................................................................................................................15
6.4 Starting operation...........................................................................................................................15
6.5 Checks during operation................................................................................................................16
6.6 Checking the refrigerant level........................................................................................................16
7Operating Parameters Setting.......................................................................................... 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 Periodical checks...........................................................................................................................18
8.3 Repairing the cooling circuit...........................................................................................................20
8.4 Tightness test.................................................................................................................................20
8.5 Hard vacuum and drying of cooling circuit.....................................................................................20
8.6 Recharging with refrigerant R410A................................................................................................21
8.7 Environmental protection...............................................................................................................21
9Troubleshooting................................................................................................................ 22

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1 General Description
THS “Lennox Telecom Split” units composed by an evaporating indoor unit THSI for ceiling or wall installation and a
motor-condensing outdoor unit THSC, mainly for electronic equipped shelters, process centers, telecommunications sites
from 4.5 to 38 kW of nominal cooling capacity.
The system provides air filtration, indoor ventilation, cooling, heating, free cooling with outdoor fresh air to assure the
useful climate in the site.
1.1 Structure
All THS units have a galvanized sheet steel supporting base and enclosing panels are painted with epoxy polyester
powder coating cured at 180°C, or, on request, painted galvanized sheet steel (RALxxxx).
1.2 Field of application
All THS units are to be used within the operating limits stated in this manual (see Tab. 1); failure to comply with said
limits will invalidate the warranties provided in the contract of sale.
Tab. 1 Operating limits
Model: THS
025
035
045
056
073
090
105
120
145
310
380
Power supply
230Vac ±10% / 1Ph / 50Hz
400Vac ±10% / 3Ph+N+PE / 50Hz
24Vdc ±16% (Emergency cooling)
48Vdc ±16% (Emergency cooling)
Outdoor
temperature
Min.
-20 °C
Max.
-
-
48.0°C
46.5°C
45.0°C
47.0°C
45.0°C
44.0°C
-
45°C
47°C
Temp. /
Humidity
conditions
Min.
19 °C / 30% R.H.
Max. 35 °C / 50% R.H.
Storage
conditions
Min.
10 °C / 90% R.H.
Max.
55 °C / 90% R.H.
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
On THS units are installed only primary brand scroll compressors of leading international manufacturers.
Today scroll compressors represent the best solution in terms of reliability, efficiency and MTBF.
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.
•High and low pressure switches.
•Schrader 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. All the remote controls use 24V signals powered by an insulating transformer.
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.

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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 to maintain the temperature set point “T” inside the shelter.
•Alarm management: - High / Low pressure;
- Dirty filters alarm;
- Air flow alarm.
•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).
See microprocessor control manual for further details, also in relation to particular customer specifications.
Fig. 1 Basic cooling circuits
THS025-035
Pos. Description Pos. Description
1
Compressor
7
Low pressure switch (LP)
2
Condenser
8
High pressure switch (HP)
3
Thermostatic valve
9
Condensing pressure probe
4
Evaporator
10
Tap
5
Filter dryer
11
Solenoid valve
6
Sight glass
12
Check valve

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THS025-035
Pos.
Description
Pos.
Description
1
Compressor
6
Sight glass
2
Condenser
7
Low pressure switch (LP)
3
Capillary tupe
8
High pressure switch (HP)
4
Evaporator
9
Condensing pressure probe
5
Filter dryer
10
Tap
THS045-056-073-090-105-120-145-310-380
Pos.
Description
Pos.
Description
1
Compressor
8
High pressure switch (HP)
2
Condenser
9
Condensing pressure probe
3
Thermostatic valve
10
Tap
4
Evaporator
11
Liquid receiver
5
Filter dryer
12
Flodding valve
6
Sight glass
13
Safety valve
7
Low pressure switch (LP)
14
Check valve

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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.

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2 Inspection / Transport
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 maneuvers. 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 trans pallet 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
minimize their environmental impact.

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3 Installation
The THS 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.
3.1 THSI - Indoor unit positioning
Bear in mind the following aspects when choosing the best site for installing the unit and the relative connections:
•position of the indoor unit next to the main heat source;
•location of power supply;
•solidity of the supporting ceiling / wall.
It is recommended to first prepare holes in the ceiling / wall for the screw anchors.
The dimensions and the positions of the holes for the screw anchors are shown below.
Fig. 2 Service area
Model: THSI A
(mm)
B
(mm)
025-035
621.6
560
045-056-073-090-105
1021.6
560
120-145
1121.6
650
Model: THSI A
(mm)
B
(mm)
310 - 380
1475
445
ONLY FOR CEILING MOUNTING
T i
A

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3.2 Free-cooling duct connections (optional)
The air conditioner may be supplied with an integrated free-cooling device (optional), which uses fresh air from outside to
cool the ambient without starting up the compressor.
The device supplies the correct cooling capacity required, through a modulating motor damper.
In this case, the back side of the unit is equipped with connections collect the outside air, as follows:
In both cases, the holes in the ceiling/wall have to be protected by rainproof grilles with pre-filter to avoid water or foreign
bodies get in the conditioner.
Outside air, taken into the room by the fan, gets out through an overpressure damper, which is installed on the ceiling /
wall of the room and is protected also by external rainproof grille.
3.3 THSC - Outdoor unit positioning
The condensing unit must be positioned outside to enable its cooling.
It is connected to the air conditioner through the refrigerant lines.
Model A
(mm)
B
(mm)
C
(mm)
D
(mm)
THSI 025-035-045-056-073-090-105-120-145-310-380
0
200
200
200
D
THSI
unit
B
THSI
unit
A
C

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3.4 Refrigerant connections
THIS OPERATION MUST BE CARRIED OUT BY AN EXPERT TECHNICIAN.
Keep refrigerant lines as short as possible and use the suggested diameter and the indication of the “Piping Design
Criteria” (attached to the unit documentation)
3.5 Lines positioning
Connect the air conditioner to the condensing unit by using refrigerant lines in hard or soft copper.
•Limit the number of pre shaped bends; if this is not possible, every bend must have a radius of at least 100mm.
•The gas line must be insulated.
•The liquid line must be kept far from heat sources; if this is not possible it has to be insulated.
•If the condensing unit is placed above the evaporating unit, the last segment of the intake tube (insulated tube)
must lean towards the condensing unit.
•If, on the other hand, the condensing unit is placed under the conditioner it is advisable to create a trap on the
intake tube.
The recommended sizes for the power cables and emergency line are shown in the related electrical drawings.

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4 THS - 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 Introductions
The simultaneous presence of liquid and vapour makes it necessary for both to be in a state of saturation ( Gibbs law ),
as shown in Fig. 3). 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:
•..withdrawal of refrigerant charge:....pressure drop inside the tank;
•..pressure drop inside the tank:........T drop & change of status;
•..T drop & change of status:.. ..........evaporation of part of the liquid, causing a cooling down of the liquid;
•cooling of liquid: thermal exchange with ambient air, further evaporation of remaining liquid;
the original pressure in the tank will be restored after a certain period of time.
Fig. 3 Gibb’s law diagram
4.2 Full vacuum and charge of the unit
Vacuum cycle
In general it is better to apply a “long” rather than a “hard” vacuum: reaching a low pressure too abruptly may in fact
cause that any remaining humidity evaporates instantaneously, thus freezing part of it.
Fig. 4 Vacuum cycle diagram
The Fig. 4 represents a vacuum cycle and an optimal subsequent pressure rise for the refrigeration devices we
manufacture. Generally in bigger refrigeration systems or if there is a suspicion of an extensive quantity of humidity in the
refrigeration circuit, the vacuum needs to be “broken” by using anhydrous nitrogen. Then the steps of evacuation need to
be repeated as described before. This operation facilitates the removal of remaining and/or frozen humidity during the
evacuation process.
P
Enthalpy h
T tank/ambient
Saturated gas
Saturated
liquid
P [Pa]
Time
200 s
6
150

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4.3 Evacuating a circuit “contaminated” with refrigerant
The first step is to remove the refrigerant from the circuit. To do this a specific machine is necessary with a drying
compressor in order to recover the refrigerant.
Refrigerants all tend to dissolve in oil (compressor sump). The Fig. 5 illustrates a specific property (Charles’ Law) of
gases, which are more soluble in liquids as the pressure increases but less soluble as the temperature increases.
Fig. 5 Charles’ law diagram
1 ) The release of refrigerant from the cooling circuit tends to cool down the oil and thus actually creates the
opposite effect by keeping more refrigerant dissolved in the oil: for this reason, it is advisable to switch on -if
available- the crankcase heater during the evacuation process.
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.
T1
T2
T oil
Pressure
% of refrigerant in oil
T3

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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
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.

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Legend:
1
= Power supply for internal unit (THSI);
2
= Power supply for external unit (THSC);
3
= Auxiliary cables.
MAIN
ELECTRICAL
PANEL
2
1
3

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6 Starting Up
6.1 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 230± 5% or 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. 6 Charles’ law diagram
The diagram above 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.
6.2 Starting up for the first time
Instructions for THSI units and THSC units
Refrigerant connection between two units (THSI + THSC)
•THSI and THSC units are both pre-charged with nitrogen.
•Following here-attached refrigeration diagram instructions (pay attention in particular to IN/OUT) start refrigeration
connections between THSI and THSC units.
•Make the vacuum in refrigerant line between in/out of the two units.
T1
T2
T oil
% of R410A in oil
Pressure
T0

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Electrical connection
•Open the frontal panel of the two units.
•Turn THSI unit QS main switch OFF.
•Switch OFF THSC unit Q01 automatic switch.
•Insert the power supply cable using one of the special holes you can find on THSI unit sides and connect it to QS
main switch.
•Following wiring diagram instructions make electrical connections between THSI and THSC units power supply
and power supply and auxiliary circuit cables.
•Connect user interface to microprocessor J10 connector (you can find it in THS wiring diagram) using a telephone
cable.
•Turn THSI unit QS main switch ON.
•Turn THSC unit Q01 automatic switch ON.
•Charge the circuit with R410A refrigerant.
•Close the panels with the matching screws.
6.3 Start up
When you give power to microprocessor, you can see the first mask of main menu where you can see the following
information:
•Indoor air temperature (Tint);
•Supply air temperature (Tsup);
•External air temperature (Text) (only Freecooling version);
•Compressors and fans state;
•Counter for evaporator fans and compressors.
In next mask (m_on_off), that you can see pushing Down , it is possibile to turn the unit on or off pushing Enter
, Down and then again Enter . It is also shown if the unit is a master or a slave unit (this is a fundamental
information for LAN operations) and configuration of local net address (Unit 1, Unit 2 or Stand Alone).
main
m_on_off
Comp OFF Tint 00.0 °C
UNIT ON:
Evap OFF Tsup 00.0 °C
No
Cond OFF Text 00.0 °C
Master
Ev 00000 Comp 00000 h
STAND ALONE UNIT
In THSI unit there is a RED coloured LED to show that alarm is present
Usage
D Always consult the “USER MANUAL” and control system manual provided with the unit when undertaking
maintenance and/or advanced set-ups.
D N.B.: In THSI unit there is not condensing pressure gouge so the value is not reliable.
6.4 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).

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6.5 Checks during operation
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.
6.6 Checking the refrigerant level
After a few hours of operation, check whether the liquid level indicator has a green ring: a yellow colour 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 THS units are pre-charged with nitrogen. 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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7 Operating Parameters Setting
7.1 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. 4 and Tab. 5.
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. 4 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
Values to be calibrated depending on the application.
Tab. 5 Setting of safety-control devices
Control device Activation Differential Resetting
Maximum pressure switch
Bar
42.0
4.0
Manual
Minimum pressure switch
Bar
2.0
1.5
Automatic
Modulating condensation control device
Bar
18.0
7.0
-
Time lapse between two compressor starts
s
480
-
-
7.2 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. 5).
7.3 Minimum pressure switch
The low pressure switch stops the compressor when the inlet pressure falls below the set value for more than 120
seconds. The switch is automatically reset when the pressure rises above the set differential (see Tab. 5).

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8 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.
8.1 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 aluminium
fins can cause superficial injuries due to cuts.
After completing maintenance jobs, always replace the panels enclosing the units and secure them
with the fastening screws provided.
8.2 Periodical checks
To guarantee a constantly satisfactory performance over time, it is advisable to carry out routine maintenance and
checks as described below. The indications below are related to standard tear and wear.
Tab. 6 Periodical checks
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.