CLIVET MR-DX 17, MR-DX 25, MR-DX 31, MR-DX 61, MR-DX 41 Installation, Operation And Maintenance Manual

C. Art. M24D40G3-03 G4D2GB-33

DIRECT EXPANSION
CLOSE CONTROL UNIT WITH
REMOTE CONDENSER

MR-DX 17-25-31-41-61-71-81

INSTALLATION,
OPERATION AND
MAINTENANCE MANUAL

GENERAL

THIS MANUAL CONTAINS THE FOLLOWING SECTIONS WHICH ARE TO BE CONSIDERED AN INTEGRAL PART

OF THE WHOLE AND ARE THEREFORE NOT TO BE DETACHED

G4D2GB-3 R4D2GB-3 E4D2GB-3 F4D2GB-3 C4D2GB-3

General Information

Reception

Electrical connections

Start-up

Controls

M4D2GB-3 L4D2GB-3 P4D2GB-3 N4D2GB-3 K4D2GB-3

Routine maintenance Water connections Refrigerant pipes Air filters

Residual risks

IMPORTANT

The contents of this manual are designed to assure the
correct installation, adjustment and maintenance of the unit;
therefore:

- read the instructions with due care and attention;

- the appliance must be installed, tested and serviced by
properly qualified personnel (law n.45, 5.3.1990) licensed in
accordance with established legislation.

• The manufacturer declines all liability, and guarantee
coverage is automatically waived, if electrical and/or
mechanical modifications are made to the unit. Tampering
and unauthorized repairs or modifications to the unit will
automatically void the guarantee.

• Observe the safety regulations in force at the time of
installation.

• Make sure that the characteristics of the mains network
conform to the data on the serial number plate inside the
electrical panel.

• Conserve this manual and the circuit diagram with care.
Make sure that they are available for consultation by the
operator whenever necessary.

• Packing materials (plastic wrappings, expanded polystyrene,
nails, etc.) are potentially hazardous and must be kept out of
reach of children. Recycle packing materials in accordance
with local bylaws.

• The water chiller must be used only for the purpose for
which it is designed. The manufacturer bears no responsibility
in the case of applications other than the specified use.

• Disconnect the unit in the case of breakdowns or
malfunctions.

• If repairs are necessary use only Clivet-approved service
centres and always insist on original spare parts.
The use of non-original parts and/or unauthorized service
centres may result in unsafe operation of the unit.

The manufacturer declines all liability for direct or indirect damage to property or injury

to persons resulting from failure to adhere to the instructions in this manual.

ADDITIONAL SAFETY PRECAUTIONS

This unit has been especially designed and manufactured so to prevent any risk to persons and health hazard.
For this reason, design solutions fit to eliminate (where possible) any cause of risk and sensibly reduce the probability of
danger have been adopted.
Please refer to the Residual risks section of this manual and strictly observe the behaviour prescriptions listed there in
order to prevent any possible risk that hasn’t been possible to avoid in the design stage.

2

GENERAL SPECIFICATIONS

Sizes 17 25 31 41 61 71 81

Standard voltage 400/3/50
Cooling capacity (1) kW 5.8 8.3 9.4 12.5 17.0 19.1 23.2
Sensible capacity (1) kW 5.3 6.9 8.1 11.2 14.6 15.5 21.4
Compr.input power (1) kW 1.5 2.3 2.9 3.0 4.7 5.6 5.8

Compressor type Scroll
N° of compressors 1
Total oil quantity kg 1.00 1.10 1.10 1.85 1.65 1.65 4

Handling zone
Frontal surface m

2

0.36 0.44 0.64 0.78

N° of rows 3 4
Fin space mm 1.8

Coonections
Gas connection mm 16 18
Liquid connection mm 12 14 16
Condensate drain mm 22

Handling zone fans (Outlet)
N° of fans 1 2
Fan diametre mm 252 280 252 280
RPM rpm 600 1100 1300 1400 1300 1400
Standard air flow l/s 472 555 639 944 1150 1888
Single motor input kW 0.35 0.55 0.35 0.55
Max. ext. static press. Pa 50
Max. ext. static press. (2) Pa 100 150 200 190 200 190 200

Standard unit weight
Shipping weight (3) kg 166 170 218 265 275 295
Lenght mm 750 925 1250 1500
Depth mm 490
Height mm 1800

Sound levels
Sound Pressure Level (4)dB(A) 47 50 51 53 54 56 58

The data refers to the following conditions:

1) Ambient air 24°C BS/ 16,9°C BU
Relative humidity 50%
External air 35°C
Standard static pressure 50Pa

2) With standard ventilating section, upon request. Contact our sales office for further details.

3) Data refers to the version with outlet downwards.

4) Sound pressure level refers to 1 metre from the outside surface of the unit operating in an open field (version with outlet
downwards)

3

POSITIONING

The units are designed for indoor installation.

• Make sure that the supporting surface is perfectly level and able to bear the full weight of the unit (see general
specifications).
Interpose a layer of rubber sheeting between the base of the unit and the supporting surface (to reduce noise and vibration).

• Observe the specified functional clearances.

ACCESSORIES

The units can be fitted with the following accessories (upon request):

- Electric heating coil
Electric heating section made from reinforced aluminium
heaters with integral fins, 2 stage operation and safety
thermostat.

- Water heating coil
Extra heating coil with 3-way balancing control valve
supplied by external hot water.

- Hot gas post-heating
Used to maintain the desired room temperature in the
event of an increase in relative humidity, adding sensible
heat to the air which has already been cooled and
dehumidified.
Operation occurs by advantageously exploiting part of the
hot gas taken from the compressor discharge, conveying it
to a coil located downstream of the cooling section.

- Steam humidifier
Immersed electrode steam humidifier with electronic
controller featuring proportional control fitted with humidity
probe on the air intake and steam distributor.

- Differential pressure switch for dirty air filters
Differential pressure switch suitable for measuring a
pressure difference between the air intake and outlet in the
filter section. In the event where the differential pressure is
greater than the set value, a remote alarm is signalled.

- Soundproofing panels
The panels are lined on the inside with micro-perforated
metal plate for the maximum sound insulation.

- Serial communication module to PC or BMS
Serial connection kit for connecting the unit control module
to a centralised control system (PC or BMS).

- Phase monitor
Used to check the presence and the correct sequence of
the phases of the power supply.

- Flooding sensor
Floor water sensor to detect leaks from the water circuit,
with remote alarm.

- Adjustable support frame
Height adjustable support frame using painted telescopic
columns (RAL 7016).
Adjustment is possible from 300-500mm or from 500­700mm.

- Adjustable support frame with duct
Height adjustable support frame using painted telescopic
columns (RAL 7016), fitted with aluminium deflector that
deviates the flow of air leaving the unit.
Adjustment is possible from 300-500mm or from 500­700mm.

- Front outlet plenum
Plenum for front air discharge, outlets with double row of
painted "aluzink" adjustable fins (RAL7016).

- Outlet plenum on three sides
Plenum for air discharge from three sides, outlets with
double row of painted adjustable fins (RAL 7016).

- Clock
Programmable clock for automatic starts, set point
changes and time band settings.

- Condensate drain pump
The condensate drain pump is used to discharge the water
present in the pan to the outside, when the outside
discharge point is higher than the pan. The pump is
controlled automatically by a built-in level sensor.

- Isolating damper
The air outlet damper, controlled by an actuator with spring
return, isolates the unit when it is not in operation.

- EU5 air filter
Filter made up of a galvanised plate frame with galvanised
and electric-welded protective mesh, and regenerable
filtering media made from polyester fibre sized with
synthetic resins.
Efficiency F5 according to CEN-EN 779 standard
(classification EU5 according to Eurovent 4/5 – average
colorimetric efficiency between 40% and 60% ASHRAE
52-76 Atm). Self-extinguishing (resistance to flame class 1

- DIN 53438).

- Liquid line solenoid valve
Solenoid valve used to prevent the unwanted migration of
refrigerant during inactivity.

4

AIR INTAKE CONFIGURATIONS

1

2

Possible configurations: 1 = outlet downwards with intake from the front (M3 or D)

2 = outlet upwards with intake from the front (M5 or U)

WARNING: When positioning the unit, leave enough space at the front to inspect the air filters and all

the components subject to checks. To the side of the fittings leave enough space for
connections and checks.

5

AIR OUTLET DIMENSIONS

CBA

D E F

C BA B D

E F G

A

A

B

B

H

I

SEZ. B-B
61-71/81

SEZ. A-A

17-25-31/41

I = air outlet downwards
II = air outlet upwards

Sizes

Dimensions

A B C D E F G H I

17-25-31 170 300 280 195 255 40 --- 630 260

41 260 335 330 173 285 32 --- 805 260

61-71 140 305 335 165 200 250 40 1130 260

81 145 333 489 200 172 285 33 1370 260

6

REMOVAL OF THE PANELS

1

3

9

4

5

6

7

8

2

Legend:

1) outlet grill for the version with outlet upwards

2) to remove the side panels, unscrew the 4 inner screws

3) right side panel

4) service panel (can be drilled for connections)

5) service connection

6) inside bottom panel

7) outside bottom panel

8) outside top panel (single piece with the outside bottom panel for sizes 17-25-31-41)

9) left side panel

7

UNIT WITH ONE FAN, INSIDE VIEW (17-25-31-41)

1

2

3

4

5

6

10

11

9

8

13

14

18

19

20

22

23

15

12

17

16

7

21

Legend:

1) control panel

2) main isolator switch

3) LCD display

4) electrical panel

5) humidity probe (optional)

6) inlet air temperature probe

7) liquid gauge

8) heater section (optional)

9) hot water or hot gas coil (optional)

10) air filter (optional EU5)

11) evaporating coil

12) steam humidifier (optional)

13) flow differential pressure switch

14) filter differential pressure switch (optional)

15) liquid line solenoid valve (optional)

16) dewatering filter

17) bypass cock

18) hot water control valve

19) outlet fan

20) compressor

21) user terminal block (with Isolert3+ option)

22) outlet air temperature probe (optional)

23) power supply input and connections

8

UNIT WITH TWO FANS, INSIDE VIEW (61-71-81)

1

2

3

4

5

6

10

11

9

8

13

14

20

21

23

24

16

12

17

15

7

22

18

19

20

Legend:

1) control panel

2) main isolator switch

3) LCD display

4) electrical panel

5) humidity probe (optional)

6) inlet air temperature probe

7) liquid gauge

8) heater section (optional)

9) hot water or hot gas coil (optional)

10) air filter (optional EU5)

11) evaporating coil

12) steam humidifier (optional)

13) flow differential pressure switch

14) filter differential pressure switch (optional)

15) liquid line solenoid valve (optional)

16) dewatering filter

17) bypass cock

18) hot water control valve

19) outlet fan

20) compressor

21) user terminal block (with Isolert3+ option)

22) outlet air temperature probe (optional)

23) power supply input and connections

For details of the water and gas connections, see the corresponding sections Water connections and Refrigerant pipes.

9

OUTLET PLENUM (optional)

A

B

C

I = air outlet from the front

II = air outlet on 3 sides

Sizes Dimensions A x B x C

17-25-31 750 x 490 x 450

41 925 x 490 x 450

61-71 1250 x 490 x450

81 1500 x 490 x450

The grills are double row (vertical - horizontal) and can be oriented as desired.

10

ASSEMBLY OF THE OUTLET PLENUM

2

1

Assembly phases:

1) unscrew the screws fastening the front grill

2) fasten the plenum to the unit at the points indicated in the figure, using the fastening screws supplied

3) replace the front grill

11

ADJUSTABLE SUPPORT FRAME (optional)

Available in two heights, 300-500 mm and 500-700 mm

I = exploded diagram * = with duct option
II = fastening the frame + = with 500-700 height option

Legend:

A) frame
B) rear duct support bracket
C) duct
D) front or rear bracket
E) adjustable leg
F) duct side bracket
G) side bracket

Assembly diagram

X) M6 screws on inserts
Y) Screw and bolt
Z) Self-tapping screw

A

*B

*C

+D

+G

E

*F

x

x

y

z

z

z

GRANDEZ

ZED

IM ENSI

O

N

I

1

7-25-314161-7181700x490xH875x490x

H1200x490x

H1450x490xH

SIZES

DIMENSIONS

CLIVET S.p.A. - Z. I. 32030 VILLAPAIERA - FELTRE (BL) Italy - Tel [phone] - Fax [phone] - sito web: www.clivet.com

The information presented in this manual is not binding and may be changed by the manufacturer without notice. All rights reserved.

DIMENSIONS

C

A

B

Sizes 17 25 31 41 61 71 81

A mm 750 750 750 925 1250 1250 1500
B mm 490 490 490 490 490 490 490
C mm 1800 1800 1800 1800 1800 1800 1800

R4D2GB-3

DIRECT EXPANSION
CLOSE CONTROL UNIT WITH
REMOTE CONDENSER

MR-DX 17-25-31-41-61-71-81

RECEPTION

CONTENTS:

1.0 - INSPECTION UPON DELIVERY

2.0 - HANDLING

2.1 - HANDLING using a FORK LIFT TRUCK or SIMILAR

2.2 - HOISTING using a CRANE or SIMILAR

3.0 - STORAGE

4.0 - REMOVING THE PACKING

5.0 - POSITIONING

1.0 - INSPECTION UPON RECEIPT

The units are delivered in special protective packing.
When it arrives check the unit has not been damaged
during transport and that it has been supplied complete
with all the parts specified in the order. If there is any

visible damage make a note of it on the transport
document, accompanied by the words: “ ACCEPTED

WITH RESERVATIONS DUE TO OBVIOUS DAMAGE
TO PACKING ” since the delivery free at factory includes

cover for damage to be borne by the insurers in
compliance with Italian law N° 450 of 22.08.85 “limite di

risarcibilità”.

IMPORTANT

EVERY OPERATION DESCRIBED BELOW MUST BE CARRIED OUT IN COMPLIANCE WITH THE SAFETY

REGULATIONS IN FORCE CONCERNING BOTH THE EQUIPMENT USED AND THE OPERATING PROCEDURES

ADOPTED.

WARNING

ALWAYS MAKE SURE THE LIFTING CAPACITY OF THE EQUIPMENT USED IS SUITABLE FOR THE WEIGHT OF THE

UNIT IN QUESTION BEFORE CARRYING OUT ANY HANDLING OPERATIONS.

Unit weight table

Size 17 25 31 41 61 71 81

Downflow weight Kg 166 170 170 218 265 275 295
Upflow weight Kg 176 180 180 231 280 290 310

2.0 - HANDLING

2.1 - HANDLING using a FORK LIFT TRUCK or SIMILAR

2.1.1 - Insert the forks in the wooden platform supplied with the unit.

2.1.2 - Start lifting the unit, making sure that it is balanced and stable. Bear in mind that the heaviest part is where the
compressor is installed.

CLIVET S.p.A. - Z. I. 32030 VILLAPAIERA - FELTRE (BL) Italy - Tel [phone] - Fax [phone] – Web site http://www.clivet.com

The information presented in this manual is not binding and may be changed by the manufacturer without notice. All rights reserved.

2.2 - HOISTING using a CRANE or SIMILAR

2.2.1 - Insert the self-balancing fork in the long side of the
wooden base supplied with the unit.

2.2.2 - Place boards on the upper edges of the unit to
protect against damage.

2.2.3 - Gradually tension the lifting straps, checking that they
remain in position.

2.2.4 - Lift the unit, ensure that the unit is perfectly balanced
and stable. Bear in mind that the heaviest part is where
the compressor is installed.

WARNING

FOLLOWING THE ADVICE ON THE OUTSIDE OF THE CARDBOARD PACKING WILL ENSURE THE UNIT REMAINS IN
PERFECT CONDITION AND OPERATES CORRECTLY, TO THE BENEFIT OF THE END USER. THIS ADVICE IS AS
FOLLOWS :

- HANDLE WITH CARE

- KEEP DRY

- UNDER NO CIRCUMSTANCES EVER PLACE OTHER OBJECTS ON TOP OF THE UNIT

3.0 - STORAGE

- Store away from: direct sunlight, rain, sand and wind

- Temperature: maximum 60°C, minimum -10°C

- Maximum humidity: 90%

4.0 - REMOVING THE PACKING

4.1 - Remove the packaging, taking care to avoid damaging
the unit.

4.2 - Remove the brackets which hold the unit on the
wooden platform using a 10 mm spanner.

4.3 - Lift the unit off the platform.

4.4 - Lower the unit to the ground in the installation point
desired

4.5 - Check for any visible damage.

4.6 - Dispose of the packing so that it is taken to specialist
collection or recycling centres (respect the regulations in
force).

5.0 - POSITIONING

5.1 - Check that the area where the unit is to be located is
level and can support the weight involved.

5.2 - Prepare the holes in the floor, in the ceiling and in the
adjacent walls for all the service connections: air outlet,
refrigerant pipes, humidifier water supply, condensate
and humidifier drain, electrical cables.
When required, position the support frame, adjust the
height so that it corresponds to the raised floor, and
check that it is level.

5.3 - Make sure there is a suitable condensate discharge
near the site where the unit is installed. If gravity draining

is not possible, an electric condensate drain pump must
be installed.

5.4 - The doors and panels should be removed and
positioned in a safe place to prevent them from being
damaged during the various phases of installation.

5.5 – The MR units with outlet upwards have been designed
to discharge the air through an upper outlet with
adjustable louvers. If an outlet duct is required, this
should be fitted before all other connections to refrigerant
pipes or the electrical line.
All ducts fastened to the unit must be easily removable
so as to allow access to the unit from above.

M4D2GB-3

DIRECT EXPANSION
CLOSE CONTROL UNIT
WITH REMOTE CONDENSER

MR-DX 17-25-31-41-61-71-81

ROUTINE MAINTENANCE

CONTENTS:

1.0 - ROUTINE MAINTENANCE

1.1 - UNIT

1.2 - WATER SYSTEM

1.3 - ELECTRICAL SYSTEM

1.4 - AIR DUCTING

1.5 - FANS

1.6 - HUMIDIFIER

1.7 - HEATERS

IMPORTANT

MAKE SURE THE UNIT IS NOT CONNECTED TO THE POWER SUPPLY BEFORE STARTING ANY MAINTENANCE OR

CLEANING OPERATIONS

1.0 - ROUTINE MAINTENANCE

This section is intended for the end user and contains
information that is extremely important to ensure the unit has
a long, trouble free service life.
Scrupulously carrying out the few simple operations
described below at regular intervals can avoid the need for
servicing by specialist personnel.
The operations which need to be carried out do not require
any special technical knowledge, involving the following
simple checks on the components of the unit:

- AIR FILTER CLEANING

- EVAPORATOR COIL

- STRUCTURE

1.1 - UNIT

1.1.1 – AIR FILTER CLEANING (SEE AIR FILTER
SECTION).

1.1.2 - EVAPORATOR COIL
IMPORTANT: accidentally touching the exchanger fins
could cause minor cuts. This operation should be carried
out using special gloves.
It is essential for the evaporator coil to provide the
maximum heat exchange. Consequently, the surface
must always be kept free of dirt and deposits.
Clean the coil, removing all impurities that may remain
on the surface. Check that the aluminium fins are not
damaged or bent, and if so, "comb" the coil using the
special tool so as to restore the initial condition and
ensure the optimum flow of air.

1.1.3 - STRUCTURE

- Check the condition of the parts forming the structure,
paying particular attention to its steel components.

- Treat any rusted points of the unit with paints designed to
eliminate or reduce this problem.

- Make sure that the unit’s casing panels are mounted firmly
in place. Poor mounting can cause abnormal vibrations
and noise.

1.2 - WATER SYSTEM

1.2.1 - CONDENSING DRAIN CONTROL
It is recommended periodical checking of the drain
condensing panel of the unit. The dust or calcareous
residues could lead to obstructions.

1.3 - ELECTRICAL SYSTEM

- Make sure there are no cuts, cracks or other signs of
deterioration indicating a possible loss of insulating
capacity in the power cable that connects the unit to the
distribution board. Contact an authorised service centre if
any maintenance operations are required

1.4 - AIR DUCTING

- Check that the fixing screws of the ducting and
corresponding structures have not loosened.
Loose screws are the source of vibrations and therefore
noise.

- Check any antivibration systems installed in the ducting to
avoid vibration transmission

1.5 - FANS
Before staring the unit each season, check the status of
the fans.

- Before starting the unit each season, check the
fastening of the fans to the structure of the unit.

- Also check that the impeller is perfectly aligned and has
not become dangerously unbalanced, as highlighted by
abnormal noise and vibrations.

2

1.6. - HUMIDIFIER

1.6.1 - Components to be checked or replaced
The steam humidifier has only one part that requires periodical
replacement: the steam production cylinder. This operation is
necessary when the lime scale that forms inside the cylinder
prevents the sufficient flow of current. This situation is signalled on
the control board by the LEVEL LED, which flashes. The frequency
of this operation depends on the supply water: the more salt or
impurities in the water, the more frequently the cylinder will need to
be replaced.

The following parts need to be checked annually:

• fill/drain solenoid valve: clean away any solid deposits, without
using compressed air, and check correct operation.

• water circuit/supply tank: clean away any deposits in the path
travelled by the water from the supply valve to the cylinder. Finally,
check that there are no leaks or drips.

• steam outlet pipe/condensate drain: check that along the path,
from the humidifier to the distributor in the duct or the room, the
pipe is not choked, which would prevent the normal release of
steam/condensate.

• humidity probes: check the condition of the probes, and if
necessary, re-calibrate them. Do not use compressed air or
solvents to clean the probe sensor.

Warning: if placing the unit out of service, completely empty
the water from the cylinder.

1.6.2 - Replacing the cylinder

To remove the cylinder, proceed as follows.

• Completely drain the water by pressing the “DRAIN” button on the
control board.

• Disconnect the power supply to the humidifier using the isolating
switch on the unit.

• Remove the steam pipe from the cylinder.

• Disconnect the electrical connections from the electrodes and
remove the plugs from the high level electrodes.

• Unscrew the nut to remove the flare coupling and the filter (when
the filter is outside the cylinder)

• Lift the cylinder to pull it out.

Before replacing it:

• The filter body does not need to be replaced, consequently, wash
it in water and reposition it on the new cylinder using the new
gasket supplied with the latter.

• Check the gasket between the cylinder and the drain assembly.

• Replace the cylinder, repeating the same operations in the reverse
order.

1 - pipe locking spring
2 - steam pipe
3 - fill pipe
4 - steam cylinder
5 - O-ring
6 - fill valve
7 - valve supports
8 - drain valve
9 - bottom sump
10 - pipe locking spring
11 - fill pipe
12 - overflow pipe

IMPORTANT

AUTHORISED PERSONNEL SHOULD BE PRESENT WHEN STARTING THE UNIT EACH SEASON, SO AS TO CARRY

OUT BOTH THE ABOVE CHECKS AND THE CHECKS ON THE REFRIGERANT CIRCUIT.

CLIVET S.p.A. - Z. I. 32030 VILLAPAIERA - FELTRE (BL) Italy - Tel [phone] - Fax [phone] - Web site: www.clivet.com

The data contained in this manual is not binding and may be changed by the manufacturer without prior notice. All reproduction, even partial, is prohibi ted.

3

1.7 – HEATERS

The unit is supplied with finned convection heaters that require periodical checking of their cleanliness and their fastening to
the support.

If requiring replacement, follow the instructions below, with reference to the figure:

1) -Remove the outlet grill A (version with outlet upwards) or the top access panel (outlet downwards).

2) - Remove the side panels B.

3) - Release the springs C that fasten the heaters to the supports.

4) - Remove the heaters D.

1

2

D

C

B

A

B

F4D2GB-3

DIRECT EXPANSION
CLOSE CONTROL UNIT WITH
REMOTE CONDENSER

MR-DX 17-25-31-41-61-71-81

START-UP

CONTENTS:

1.0 - PRELIMINARY CHECKS

1.1 - ELECTRICAL PANEL

1.2 - COMPRESSORS

2.0 – STARTING THE UNIT

4.0 – SET POINT AND INTERFACE

1.0 - PRELIMINARY CHECKS

- Check that the unit is positioned correctly and that the
air and water connections have been performed
correctly.

- Check the power supply voltage and frequency:

WHICH MUST BE WITHIN THE FOLLOWING VALUES

400/3/50 ± 10%
The phase unbalance must be less than a maximum of
3%

(see calculation example).
Calculation example:

L1 - L2 = 388V
L2 - L3 = 379V
L3 - L1 = 377V

The mean of the values measured is obtained by:

388 379 377

3

++

= 381

The maximum deviation of the mean is obtained by:

388-381=7 V

The unbalance is obtained by:

7

381

x 100 = 1,83% (accettabile)

IMPORTANT:
The following operations must only be performed by
suitably trained and authorised personnel.
Before starting the following operations, ensure that
the power supply is disconnected from the unit at the
source and that the isolator device is padlocked and
marked by a special warning sign.

1.1 - ELECTRICAL PANEL

- Check that the screws fastening the wires to the
electrical components in the panel are tight (vibrations
during handling and transport may have caused these
to loosen).

- Close the control and power circuit breakers.

- Close the door on the electrical panel.

- Connect the power line to the unit.

- Close the main line isolator switch.

1.2 - COMPRESSORS

The scroll compressors used in these units are very noisy
if rotating in the wrong direction. If this occurs, reverse
two phases of the electrical power line. The power input
of the compressor must be lower than the FLA value
declared (seen under “electrical connections”).

(acceptable)

CLIVET S.p.A. - Z. I. 32030 VILLAPAIERA - FELTRE (BL) Italy - Tel [phone] - Fax [phone] - sito web http://www.clivet.com

The information presented in this manual is not binding and may be changed by the manufacturer without notice. All rights re served.

2.0 – STARTING THE UNIT

When the unit is powered, with the main isolating switch
rotated in position I, and in standby, the “line” LED on the
interface is on and the display shows:

− Clock and weekday, if the optional clock card is
installed.

− Room temperature and corresponding unit of
measure.

− Ambient humidity and corresponding unit of measure
in % (if the optional humidifier and probe are
present).

− The OFF status of the remote switch, if present.

− Thermometer, indicating that the value displayed is

the temperature.

At this point, turn the remote on/off switch on (on the
display, the text OFF will be replaced by ON). If the
switch is not present, proceed as follows.

Press the On/Off button on the interface, causing the
following actions:

− The green “on” LED associated with the On/Off
button will light up.

− The display will show the symbols corresponding to
the actuators that, depending on the set point and
the parameters set, should start operating.

− The compressor starts after a delay of 20 seconds
from the start of the fan, which itself starts
immediately if requested to operate. The fan, in all
phases (cooling, heating, humidification and
dehumidification) always starts first.

The following are the symbols shown on the display
when the unit is operating, indicating the operating status
of the unit.

3.0 – STOPPING THE UNIT

To stop the unit, press the ON/OFF button; all the
actuators will switch off except for the fan, which will stop
after a delay of 20 seconds. The two green LEDs go off
to signal that the unit is in standby.
At this point, the isolating switch on the door of the panel
can be turned to position 0.

4.0 – SET POINT AND INTERFACE

To set the set point and use the interface, refer to the
section on the control of the unit.

SHORT DISPLAY LEGEND

Fan on

Cooling active, 1 and 2 refer to the cooling actuators

Heating active, 1 and 2 refer to the heating actuators (optional).

Humidification active (optional).

Dehumidification active (optional)

C4D2GB-3

DIRECT EXPANSION
CLOSE CONTROL UNIT WITH
REMOTE CONDENSER

MR-DX 17-25-31-41-61-71-81

CONTROLS

CONTENTS:

1.0 – DISPLAY AND KEYPAD

1.1 - THE DISPLAY

1.2 - OPERATING SIGNALS

1.3 - THE KEYPAD

1.4 - MODIFYING THE PARAMETERS

1.5 - CONTROL PARAMETERS

1.6 - READ ONLY PARAMETERS

1.7 - DIAGRAMS

2.0 - ALARMS

2.1 - MANUAL, AUTOMATIC ALARMS AND RESET

2.2 - SHUT-DOWN SIGNAL

2.3 - OPTIONAL ALARMS

2.4 - DIAGNOSTICS

3.0 - OPTIONS

1.0 – DISPLAY AND KEYPAD

Table 1

Room temperature in programming mode displays the value
of the parameter

Temperature unit of measure: degrees Centigrade/Fahrenheit

Ambient humidity
in programming mode displays the no. of the parameter

Relative humidity unit of measure

Buzzer active

Hour counter limit exceeded

Off from time bands

Time bands active

External contact status:

- ON – enable unit

- OFF – unit in standby

Indicates that the value displayed is the temperature

(without this symbol on, the Set Point is displayed)

Time band selected

Dehumidification active

Fan active :% fan speed

Cooling active:

- number (1 or 2) of cooling actuators; % opening of
cooling valve, or (in shelter mode) % opening of
freecooling damper

Heating active:

- number (1 or 2) of heating actuators

- % opening of valve

Humidification active: % steam production

Programming phase

- set password

- lock parameter modification

(In clock operation) weekday

-

display clock

- setup clock

1.1 - THE DISPLAY
The display shows the main values monitored, and the status
of the unit and the actuators.
Table 1 to the side lists the symbols and the texts shown on
the display, with the corresponding meanings.

N.B. Fig. 1 illustrates all the symbols and texts shown on
the display when the controller is started.

Fig. 1

1.2 - OPERATING SIGNALS

The main states of the controller (power supply, alarm active
and remote On/Off input status) are indicated by 3 LEDs on the
front panel.

Meaning of the LEDs:
Line LED (yellow): controller powered
Alarm LED (red): alarm active on the unit (the siren symbol on

the display is on only when the buzzer is active)
On LED (green): unit On. The effective On status of the unit
may also depend on the position of the remote On-Off switch,
on the active time band (function enabled only if the clock card
is fitted), on the standby condition transmitted by the master
unit (when a series of units are in rotation), and is indicated by
the fan symbol.

The ON-OFF symbols on the display indicate the status of
the remote on/off switch. If the switch is not fitted, the
display will always show the ON symbol.

2

1.3 - THE KEYPAD

ON/OFF: Switches the status of the unit; if on,
pressing the button places it in Standby; vice-versa,
it is reactivated.

ALARM / Prg: When an alarm is present, mutes the
buzzer; if the clock option is present, in programming
phase sets the time.

UP: In programming phase, scrolls or increases the
value of the parameters. If the clock option is present,

each time the button is pressed the following are
displayed, in sequence: the current time, the date
and the room temperature.

DOWN: Held displays the set point. In programming
phase, scrolls or decreases the value of the
parameters.

ENTER / Sel: Pressed for 5s accesses the
parameters. In programming phase, changes the
value of the selected parameter (see par. 1.4 ­Modifying the parameters). If the clock option is

present, in programming phase sets the time.

UP + DOWN pressed together for 2s reset the alarms.

1.4 - MODIFYING THE PARAMETERS

− Press the ENTER button for 5s, the value of the first
accessible parameter will be displayed, and in the top
right, the code of the parameter, flashing.

− Scroll the various parameters using the UP and DOWN
buttons.

− Pressing ENTER again displays the value, flashing, of
the selected parameter, while the UP and DOWN
buttons change the value.

− Press ENTER again to temporarily save the new value.
Then, use the UP and DOWN buttons to scroll the menu
of the parameters, repeating the previous operations for
each parameter to be modified.

− Press the ALARM button, on the other hand, to store the
changes made.

Adjusting the contrast of the LCD

The contrast of the display can be adjusted according to
the effective angle of viewing.
Pressing the ENTER and UP buttons together increases
the value, vice-versa, ENTER and DOWN decrease it.

1.5 - CONTROL PARAMETERS

r1 Temperature set point (cooling)

Used to set the temperature set point in cooling (see
diagrams at the end of the paragraph).

Default: 20.0

r2 Cooling differential

Used to set the differential in cooling mode (see
diagrams at the end of the paragraph).

Range: 0.1-11.0°C
Default: 3.0

r3 Heating differential

Used to set the differential in heating mode (see
diagrams at the end of the paragraph).

Range: 0.1-11.0°C
Default: 2.0

r4 Temperature dead zone

Used to set the dead zone (see diagrams at the end of
the paragraph). When the air inlet temperature is inside
the dead zone, all the actuators are off, except for when
the compressor is operating following a dehumidification
request.

Range: 0.1-11.0°C
Default: 1.0

WARNING: THE PARAMETERS FROM r5 TO r8 ARE
PRESENT ONLY TOGETHER WITH THE HUMIDITY
PROBE OPTION

r5 Humidity set point

Sets the humidity set point (see diagrams at the end of
the paragraph).

Default: 50

r6 Humidification differential

Sets the differential for humidification (see diagrams at
the end of the paragraph).

Range: 1-20%rH
Default: 4

r7 Dehumidification differential

Sets the differential for dehumidification (see diagrams at
the end of the paragraph).

Range: 1-20%rH
Default: 3

r8 Humidity control dead zone

Used to set the dead zone (see the diagram at the end of
the paragraph). When the humidity measured by the
humidity probe is inside this zone, the humidifier and the
dehumidification function are not active.

Range: 1-20%rH
Default: 2

r9 Temperature set point (heating)

Heating set point, does not affect the operation of the
machine, its setting is superfluous.

Default: 18.0

rt Time band setting

If the clock option is installed, used to set time band
mode (see chap. 3)
0= time bands disabled
1= temperature monitoring
2= On/Off

Range: 0-2 flags
Default: 0

1.6 - READ ONLY PARAMETERS

rP Humidity probe reading
Percentage of humidity. Only with probe installed.
rr Probe B4 reading
Outlet air temperature. Displayed only with probe
installed.
c9 Hour counter, compressor 1
cA Hour counter, compressor 2

Indicates the number of operating hours for compressor 1
and/or 2. The reading of cA has no meaning, as only one
compressor is used.

FA Hour counter, outlet fan

Indicates the number of operating hours of the fan.

FC Hour counter, filter

Indicates the number of operating hours of the filter.

Hr Software version

Displays the version of the software.

3

1.7 - DIAGRAMS

Temperature control diagram

Compressor + electric heaters

The diagram to the side highlights the operation of
the compressor and the heaters to bring the
temperature from outside the limits r2 and r3 to
limit r4. In cooling mode, the compressor starts
operating at the end of r2, across the entire band,
until the temperature returns inside the dead zone
r4. In the heating phase, the 2 triads of heaters
start respectively at half of the differential (r3/2)
and at the actual limit (r3/2+r3/2). When the
temperature starts returning the second triad is
deactivated at half of the differential (r3/2) and the
first triad is deactivated at r4.
Ht and Lt are respectively the high and low
temperature limits, over which the alarms Ht and
Lt are activated.
These alarms are reset automatically 1 degree
above (Lt) and 1 degree below (Ht) the threshold.

Temperature control diagram

Compressor + 3-pos. valve

The diagram to the side is typical of machines
fitted with a water heating coil. The trend
highlights the operation of the water valve and the
compressor to bring the temperature back from
outside the differential limits r2 and r3 to the limit
of the dead zone r4. The zone r3 represents the
modulation band for the heating actuator, while r2
is the operating band of the compressor. The
valve opens further the more the temperature
moves away from the set point (r1), and reaches
the maximum value outside of the differential limit
r3.

Humidity control diagrams

Humidification + dehumidification control

The diagram highlights the operation of the
compressor and the humidifier to bring the value
of the humidity, when outside of the limits of the
differential r6 and r7, back into the dead zone r8.
In the dehumidification phase, the compressor
operates even if the temperature is below the set
point r1, while in humidification phase the
humidifier operates along a ramp (0-10Vdc),
proportionally to the humidity request.
In dehumidification mode, exceeding the LOW
LIMIT, equal to 3/2*r3 (see the temperature
control diagram above) causes the compressor to
stop, ignoring the dehumidification request, while
the heating actuators (hot water coil, heaters or
hot gas coil), which are activated as soon as the
temperature falls below the set point, continue to
operate according to the type of control set, until
the temperature reaches the SET POINT, above
which the compressor starts operating again so as
to dehumidify. Exceeding the high (HH) and low
(LH) humidity limits produces the corresponding
alarms, with reset automatic and an hysteresis of
1% RH.

4

Temperature control diagram

Compressor + post-heating coil

Dehumidification

only

-{}­The post-heating hot gas coil, unlike the other heating
actuators, starts when the temperature is below the set point
and the machine is operating in dehumidification mode. The
two conditions, temperature and humidity, are controlled at
the same time.
The coil is activated over the lower limit of r3, and operates
across the entire band until the lower limit of r4.

2.0 - ALARMS

2.1 - MANUAL, AUTOMATIC ALARMS AND RESET

When an alarm occurs, the unit performs the following
actions:

− activation of the buzzer and display of a signal (with
unit On);

− energising of the alarm relay.

− display of the alarm code and red LED on.

In this condition, pressing the ALARM button mutes the
buzzer.
When the alarms with automatic reset are no longer
present, if no alarms with manual reset are active, the
following occurs:

− buzzer off;

− deactivation of the alarm relay;

− red alarm LED switches off;

− reactivation of the actuators stopped due to the

alarm.

Pressing the UP and DOWN buttons together, for 2s,
cancels the display of the alarm code.
In the event of alarms with manual reset, pressing the UP
and DOWN buttons together, for 2s, performs the
following actions:

− deactivation of the alarm relay;

− red alarm LED switches off;

− reactivation of the actuators stopped due to the

alarm.
The alarm messages are displayed cyclically in the
progressive order indicated in Table 2. At the end of the
cycle the percentage of humidity is displayed (if featured)
for 6 s.

2.2 - SHUT-DOWN SIGNAL

A relay that is de-energised when an alarm occurs is
used for the alarm signal. The relay features a 24V, 1A
changeover contact, available via the user terminal block.
Terminal C6: power supply common.
Terminal NC6: NC contact for the remote alarm signal.
Terminal NO6: NO contact for the remote “no alarm”
signal.

2.3 - OPTIONAL ALARMS

Flooding, fire or smoke sensor.

Optional devices are available to signal flooding or the
presence of fire or smoke. The alarm signal, which is also
active in standby, stops the unit, and it can only be reset
manually once the alarm conditions are no longer
present.

Phase monitor.

This measures the exact connection sequence of the
phases, activating an alarm if the machine is not powered
as shown on the wiring diagram. The alarm is manually
reset.

Differential pressure switch for dirty filters

When the air filter is dirty or clogged and the flow-rate of
the air intake falls below 40-50%, the filter differential
pressure switch is activated. A signal-only alarm is
activated, which is reset automatically when the causes
are no longer present.