Julabo FL2503 User manual

English
Operating manual
Recirculating Coolers
FL2503 FLW2503
FL2506 FLW2506
FL4003 FLW4003
FL4006 FLW4006
RS23
2
A
LARM
°C
FL2506
Changes without prior notification reserved
Printed in Germany
1.951.4829 BE0 10/08 Druck: 09.10.2008
Innovative Temperature Technology
JULABO Labortechnik GmbH
77960 Seelbach / Germany
+49 (0) 7823 / 51-0
+49 (0) 7823 / 24 91
|[email protected]
Þwww.JULABO.de
19514829_FL25xx_FL40xx.doc

2
Congratulations!
You have made an excellent choice.
JULABO thanks you for the trust you have placed in us.
This operating manual has been designed to help you gain an understanding of the principles of
operating and possibilities of our circulators. For optimum utilization of all functions, we recommend
that you thoroughly study this manual prior to beginning operation.
EC Conformity
The products described in the operating instructions conform to the requirements of
the following European guidelines:
Low voltage regulations with respect to legal harmonization of the member countries concerning
electric devices for use within certain voltage limits.
EMC guideline with respect to legal harmonization of the member countries concerning
electromagnetic compatibility.
JULABO Labortechnik GmbH
Eisenbahnstr. 45
77960 Seelbach / Germany
Quality Management System
ISO 9001
2000
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The JULABO Quality Management System:
Development, production and distribution of temperature application instruments for
research and industries conform to the requirements according to
DIN EN ISO 9001:2000.
Certificate Registration No. 01 100044846

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TABLE OF CONTENTS
1. Use according to intended purpose.............................................................................................. 4
1.1. Description........................................................................................................................ 4
2. Operator responsibility – Safety recommendations...................................................................... 4
2.1. Handling............................................................................................................................ 4
2.2. Use.................................................................................................................................... 5
2.3. Disposal ............................................................................................................................ 5
3. Technical specifications................................................................................................................ 6
3.1. Warning functions and safety installations...................................................................... 10
3.2. Cooling water connection................................................................................................ 11
4. Safety notes for the user ............................................................................................................ 12
4.1. Safety recommendations ................................................................................................ 12
5. Unpacking and checking ............................................................................................................ 13
6. Installation .................................................................................................................................. 13
6.1. Tubing............................................................................................................................. 15
7. Operating controls and functional elements ............................................................................... 16
8. Operating procedures................................................................................................................. 18
8.1. Bath fluids ....................................................................................................................... 18
8.2. Power connection ........................................................................................................... 18
8.3. Filling............................................................................................................................... 19
8.4. Switching on / Start - Stop .............................................................................................. 19
8.5. Setting the feed pressure................................................................................................ 20
8.6. Setting the temperatures................................................................................................. 20
8.7. AUTOSTART ON / OFF.................................................................................................. 20
8.8. Remote control: activate – deactivate............................................................................. 21
9. Safety installations...................................................................................................................... 21
9.1. Excess temperature protection ....................................................................................... 21
9.2. Low level protection ........................................................................................................ 21
10. Troubleshooting guide / Error messages .......................................................................... 22
11. Electrical connections ....................................................................................................... 24
12. Remote control..................................................................................................................25
12.1. Setup for remote control ................................................................................................. 25
12.2. Communication with a PC or a superordinated data system .......................................... 25
12.3. List of commands............................................................................................................ 26
12.4. Status messages ............................................................................................................ 26
12.5. Error messages............................................................................................................... 27
13. Cleaning / repairing the unit .............................................................................................. 28
14. JULABO Service – Online remote diagnosis..................................................................... 30
14.1. Draining........................................................................................................................... 31
15. Adequate storing of operating manual .............................................................................. 31
16. Warranty conditions .......................................................................................................... 32

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1. Use according to intended purpose
JULABO recirculating coolers have been designed for temperature application to specific fluids. The
pump connections can be used for cooling applications in an external circuit at a constant temperature.
JULABO recirculating coolers are not conceived for direct temperature application to
food and luxury articles or pharmaceutical and medico-technical products. Direct
temperature application means: Unprotected contact of the object with the bath
medium (bath fluid).
1.1. Description
PID1
RS232
The recirculating coolers are operated via the splash-proof keypad. The
implemented microprocessor technology allows to set and to store the setpoint that
can be indicated on the LED temperature display.
The PID temperature regulation is used to withdraw heat from the bath fluid by
means of the cooling machine and to automatically regulate the required need.
Electrical connections:
1. The serial interface RS232 allows modern process technology without
additional interface.
2. Alarm output for external alarm message.
Manually adjustable by-pass (handwheel) to reduce the pump capacity
(e. g. for glass equipment).
2. Operator responsibility – Safety recommendations
The products of JULABO Labortechnik GmbH warrant a safe operation if installation, operation and
maintenance is carried out according to common safety regulations. This section informs you about
potential dangers that may arise from operating the recirculating cooler and also mentions the most
important safety precautions.
The operator is responsible for the qualification of the personnel operating the units.
The operator should be constantly informed about the dangers involved with their job activities as well
as preventive actions.
Make sure all persons expected to carry out operation, installation and maintenance of the unit read
and understand the safety information and operating instructions.
When using hazardous materials, the circulator may only be operated by persons that are absolutely
familiar with these materials and the circulator. These persons must be fully aware of possible risks.
If you have any questions concerning the operation of your unit or the information in this manual,
please contact us!
Contact JULABO Labortechnik GmbH
Eisenbahnstraße 45
77960 Seelbach / Germany
[phone] |[email protected]
[phone] Þwww.JULABO.de
2.1. Handling
You received a product conceived for industrial use. Nevertheless, avoid strikes to the housing,
vibrations, damages to the keypad foil (keys, display) or contamination.
Make sure the product is regularly checked for proper condition. Regularly check (at least every
2 years) the proper condition of the mandatory, warning, prohibition and safety labels.
Take care that the mains supply features a low impedance to avoid any negative affects on the

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instrument being operated in the same mains.
This unit is designed for operation in a controlled electromagnetic environment. This means that
transmitting devices (e.g. cellular phones) should not be used in the immediate vicinity. Magnetic
radiation may influence other units with components susceptible to magnetic fields
(e.g. a monitor). We recommend to keep a minimum distance of 1 m.
Permissible ambient temperature: max. 40 °C, min. 5 °C.
Permissible relative air humidity: 50 % (40 °C).
Do not store in an aggressive atmosphere. Protect from contaminations. Do not expose to sunlight.
Appropriate Operation
Only qualified personnel is authorized to perform configuration, installation, maintenance and repairs of
the recirculating cooler. Untrained personnel should be instructed by trained personnel.
2.2. Use
For the use according to the intended purpose, special material requirements have to be respected
(bath fluids). Only use non-acid and non corroding materials. Observe all warnings for the used
materials (bath fluids) and the respective instructions (safety data sheets).
Only use the unit in well ventilated areas. (see page 13).
The recirculating coolers are not for use in explosive atmosphere
When using hazardous materials, the user must attach the enclosed safety labels to the front of the
unit so they are well visible.
Warning label W00:
Colors: yellow, black
Danger area.
Attention! Observe instructions.
(operating manual, safety data sheet)
Mandatory label M018
Colors: blue, white
Carefully read the user information prior to beginning
operation
Scope: EU
Semi S1-0701
Table A1-2 #9
Carefully read the user information prior to beginning
operation
Scope: NAFTA
Observe the instructions in the manuals for instruments of a different make that you connect to the
circulator, particularly the respective safety recommendations. Also observe the pin assignment of
plugs and technical specifications of the products.
2.3. Disposal
This unit contains the refrigerants R134a or R404A – at this time considered not to have any negative
effects on the ozone layer. However, during the long operating period of the unit, disposal prescriptions
may change. So only qualified personnel should take care of disposal.
Valid in EU countries:
Directive 2002/96/EC of the European Parliament and of the Council of 27 January
2003 on waste electrical and electronic equipment (WEEE).
This directive requires electrical and electronic equipment marked with a
crossedout trash can to be disposed of separately in an environmentally friendly
manner.
Contact an authorized waste management company in your country.
Disposal with household waste (unsorted waste) or similar collections of municipal
waste is not permitted!

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3. Technical specifications
Recirculating Cooler
Cooling
FL2503 FLW2503
air cooled water cooled
Working temperature range °C -20 ... +40 -20 ... +40
Temperature stability °C ±0.5
Temperature selection: digital
via key pad indication on LED-DISPLAY
remote control via personal computer indication on monitor
Temperature indication: LED-DISPLAY
Resolution °C 0.1
Temperature control PID 1
Temperature sensor Pt 100
Excess temperature protection 85 °C - fixed value
Low liquid level protection float switch
Cooling capacity
Medium: Mixture water-glycol
°C
kW
+20 0 -10 +20 0 -10
2.5 1.5 1.2 2.7 1.7 1.3
Cooling compressor 1-stage
Refrigerant R404A
Electrical connections:
Computer interface RS232
Alarm output for external alarm signal
Circulating pump:
discharge, max. at 0 bar l/min 40 40
pressure, adjustable at 0 Liter bar 0.5 ... 3.0 0.5 ... 3.0
Feed pressure indication bar Manometer Manometer
Filling level indicator sight glass
Filling volume from ... to liters 19 ... 27
Dimensions (WxLxH) cm 60x76x115
Weight kg 146 143
Ambient temperature range °C 5 ... 40
Return flow temperature °C 80 max.
Cooling water
Flow rate at 20 °C inlet temperature l/min ----- 4.1
IP class according to IEC 60 529 IP 21
Mains power connection 230 V/50 Hz V/ Hz 207-253 / 50 207-253 / 50
Current input at 230 V A 11 12
Mains power connection 208 - 220 V/60 Hz V/ Hz 197 - 242 / 60 197 - 242 / 60
Current input at 208V / 220 V A 13 ----
All measurements have been carried out at: rated voltage and frequency,
ambient temperature: 20 °C

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Recirculating Cooler
Cooling
FL2506 FLW2506
air cooled water cooled
Working temperature range °C -20 ... +40 -20 ... +40
Temperature stability °C ±0.5
Temperature selection: digital
via key pad indication on LED-DISPLAY
remote control via personal computer indication on monitor
Temperature indication: LED-DISPLAY
Resolution °C 0.1
Temperature control PID 1
Temperature sensor Pt 100
Excess temperature protection 85 °C - fixed value
Low liquid level protection float switch
Cooling capacity
Medium: Mixture water-glycol
°C
kW
+20 0 -10 +20 0 -10
2.5 1.0 0.3 2.5 1.0 0.3
Cooling compressor 1- stage
Refrigerant R404A
Electrical connections:
Computer interface RS232
Alarm output for external alarm signal
Circulating pump:
discharge, max. at 0 bar l/min 60 60
pressure, adjustable at 0 Liter bar 0.5 ... 6.0 0.5 ... 6.0
Feed pressure indication bar Manometer Manometer
Filling level indicator sight glass
Filling volume from ... to liters 19 ... 27
Dimensions (WxLxH) cm 60x76x115
Weight kg 158 160
Ambient temperature range °C 5 ... 40
Return flow temperature °C 80 max.
Cooling water
Flow rate at 20 °C inlet temperature l/min ----- 4.1
IP class according to IEC 60 529 IP 21
Mains power connection 230 V/50 Hz V/ Hz 207-253 / 50 207-253 / 50
Current input at 230 V A 14 15
Mains power connection 208 - 220 V/60 Hz V/ Hz 197 - 242 / 60 197 - 242 / 60
Current input at 208V / 220 V A 16 ------
All measurements have been carried out at: rated voltage and frequency,
ambient temperature: 20 °C

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Recirculating Cooler
Cooling
FL4003 FLW4003
air cooled water cooled
Working temperature range °C -20 ... +40 -20 ... +40
Temperature stability °C ±0.5
Temperature selection: digital
via key pad indication on LED-DISPLAY
remote control via personal computer indication on monitor
Temperature indication: LED-DISPLAY
Resolution °C 0.1
Temperature control PID 1
Temperature sensor Pt 100
Excess temperature protection 85 °C - fixed value
Low liquid level protection float switch
Cooling capacity
Medium: Mixture water-glycol
°C
kW
+20 0 -10 +20 0 -10
4.0 2.4 1.5 4.3 2.5 1.6
Cooling compressor 1- stage
Refrigerant R404A
Electrical connections:
Computer interface RS232
Alarm output for external alarm signal
Circulating pump:
discharge, max. at 0 bar l/min 40 40
pressure, adjustable at 0 Liter bar 0.5 ... 3.0 0.5 ... 3.0
Feed pressure indication bar Manometer Manometer
Filling level indicator sight glass
Filling volume from ... to liters 19 ... 27
Dimensions (WxLxH) cm 60x76x115
Weight kg 148 143
Ambient temperature range °C 5 ... 40
Return flow temperature °C 80 max.
Cooling water
Flow rate at 20 °C inlet temperature l/min ----- 6.6
IP class according to IEC 60 529 IP 21
Mains power connection 230 V/50 Hz V/ Hz 360-440/3Phases/50 360-440/3Phases/50
Current input at 230 V A 8 8
Mains power connection 208 - 220 V/60 Hz V/ Hz 207-253/3Phases/60 207-253/3Phases/60
Current input at 208V / 220 V A 11 ------
All measurements have been carried out at: rated voltage and frequency,
ambient temperature: 20 °C

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Recirculating Cooler
Cooling
FL4006 FLW4006
air cooled water cooled
Working temperature range °C -20 ... +40 -20 ... +40
Temperature stability °C ±0.5
Temperature selection: digital
via key pad indication on LED-DISPLAY
remote control via personal computer indication on monitor
Temperature indication: LED-DISPLAY
Resolution °C 0.1
Temperature control PID 1
Temperature sensor Pt 100
Excess temperature protection 85 °C - fixed value
Low liquid level protection float switch
Cooling capacity
Medium: Mixture water-glycol
°C
kW
+20 0 -10 +20 0 -10
4.0 1.9 0.9 4.0 1.9 0.9
Cooling compressor 1- stage
Refrigerant R404A
Electrical connections:
Computer interface RS232
Alarm output for external alarm signal
Circulating pump:
discharge, max. at 0 bar l/min 60 60
pressure, max. at 0 liter bar 0.5 ... 6.0 0.5 ... 6.0
pressure, adjustable at 0 Liter
Feed pressure indication bar Manometer Manometer
Filling level indicator sight glass
Filling volume from ... to liters 19 ... 27
Dimensions (WxLxH) cm 60x76x115
Weight kg 157 160
Ambient temperature range °C 5 ... 40
Return flow temperature °C 80 max.
Cooling water
Flow rate at 20 °C inlet temperature l/min ----- 6.6
IP class according to IEC 60 529 IP 21
Mains power connection 230 V/50 Hz V/ Hz 360-440/3Phases/50 360-440/3Phases/50
Current input at 230 V A 12 13
Mains power connection 208 - 220 V/60 Hz V/ Hz 207-253/3Phases/60 207-253/3Phases/60
Current input at 208V / 220 V A 16 ------
All measurements have been carried out at: rated voltage and frequency,
ambient temperature: 20 °C

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3.1. Warning functions and safety installations
Excess temperature protection 85 °C - fixed value
Low liquid level protection float switch
Alarm message optical + audible (permanent)
Excess temperature - Warning function 75 °C
Overload protection for compressor and pump motor
Classification according to DIN 12876-1 class I
Environmental conditions according to IEC 61 010-1:
Use only indoor.
Altitude up to 2000 m - normal zero.
Ambient temperature: +5 ... +40 °C
Air humidity:
Max. rel. humidity 80 % for temperatures up to +31 °C,
linear decrease down to 50 % relative humidity at a temperature of +40 °C
Max. mains fluctuations of ±10 % are permissible.
The unit corresponds to Class I
Overvoltage category II
Pollution degree 2
Caution:
The unit is not for use in explosive atmosphere
Standards for interference resistance according to EN 61326-1
This unit is an ISM device classified in Group 1 (using high frequency for internal purposes) Class A
(industrial and commercial range).

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3.2. Cooling water connection
Only for water cooled models - FLW:
Cooling water pressure (IN / OUT ) max. 4,5 bar
Difference pressure (IN - OUT ) 2 bar to 4,5 bar
Flow rate on FLW250x typical 4,1 l/min
Flow rate on FLW400x typical 6,6 l/min
Cooling water temperature <20 °C
Recommended quality of cooling water:
pH – value 7,5 to 9,0
Sulfate [SO4 2- ] < 100 ppm
Hydrocarbonate [HCO3- ] / Sulphate [SO4 2-] > 1 ppm
Hardness [Ca2+, Mg2+] / [HCO3-] > 0,5 dH
Alkalinity 60 ppm < [HCO3-] < 300 ppm
Conductivity < 500 μs / cm
Chloride (CL-) < 50 ppm
Phosphate (PO43-) < 2 ppm
Ammonia (NH3) < 0,5 ppm
Free Chlorine < 0,5 ppm
Ferri Ions (Fe3+ ) < 0,5 ppm
Mangano Ions (Mn2+) < 0,05 ppm
Carbon dioxide (CO2) < 10 ppm
Hydrosulfide (H2S) < 50 ppm
Content of oxygen < 0,1 ppm
Algae growth impermissible
Suspended solids impermissible
Notice:
Danger of corrosion of heat exchanger due to unsuitable quality of cooling
water.
•Due to its high content of lime hart water is not suitable for cooling and causes
calcination of the heat exchanger.
•Ferrous water or water containing ferrous particles will cause formation of rust
even in heat exchangers made of stainless steel.
•Chlorous water will cause pitting corrosion in heat exchangers made of stainless
steel.
•Due to its corrosive characteristics distilled and deionized water is unsuitable and
will cause corrosion of the bath. .
•Due to its corrosive characteristics sea water is not suitable.
•Due to its microbiological (bacteria) components which settle in the heat
exchanger untreated and unpurified river water and water from cooling towers is
unsuitable.
•Avoid particulate matter in cooling water.
•Avoid putrid water.

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4. Safety notes for the user
In addition to the safety warnings listed above, warnings are posted throughout the
manual. These warnings are designated by an exclamation mark inside an equilateral
triangle. „Warning of a dangerous situation (Attention ! Please follow the
documentation).“
The danger is described according to an alarm keyword.
Read and follow these important instructions.
Warning:
Describes a possibly highly dangerous situation. If this is not avoided, serious injury
and danger to life could result.
Caution:
Describes a possibly dangerous situation. If this is not avoided, slight or minor injuries
could result.
A warning of possible damage can also be contained in the text.
Notice:
Describes a possibly harmful situation. If this is not avoided, the product or anything in
its surroundings can be damaged.
4.1. Safety recommendations
Follow the safety recommendations to prevent damage to persons or property. Further,
the valid safety instructions for working places must be followed.
•Only connect the unit to a power socket with earthing contact (PE – protective
earth)!
Recommendation in case of single-phase current supply (e.g. FL250x):
The safety cutouts of the house wiring should have the trait „C“ (C16A).
•The power supply plug serves as safe disconnecting device from the line and must
be always freely accessible.
•Place the instrument on an even surface on a pad made of non-inflammable
material.
•Make sure you read and understand all instructions and safety precautions listed in
this manual before installing or operating your unit.
•Never operate the unit without bath fluid in the bath.
•Do not drain the bath fluid while it is hot or cold!
Check the temperature of the bath fluid prior to draining (by
switching the unit on for a short moment for example).
•Employ suitable connecting tubing.
Make sure that the tubes are securely attached.
•Never operate damaged or leaking equipment.
•Always turn off the unit and disconnect the mains cable from the power source
before performing any service or maintenance procedures, or before moving the
unit.
•Always empty the bath before moving the unit.
•Never operate equipment with damaged mains power cables.
•Risk of injury for hands. Close cover carefully.

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5. Unpacking and checking
Unpack the recirculating cooler and accessories and check for damages
incurred during transit. These should be reported to the responsible carrier,
railway, or postal authority, and a request for a damage report should be
made. These instructions must be followed fully for us to guarantee our full
support of your claim for protecting against loss from concealed damage. The
form required for filing such a claim will be provided by the carrier.
Lifting device for transportation by crane see page 16
6. Installation
•Place the unit on an even surface on a pad made of non-flammable
material. Using the castors (10a, 10b) move the unit to the intended
location.
For better stability, apply the holding breaks on the front casters (10a).
•Cooling machine, pump motor and electronics produce intrinsic heat that is
dissipated via the venting openings.! Never cover these openings!
•Keep at least 20 cm of open space on the front and rear venting grids.
•The place of installation should be large enough and provide sufficient air
ventilation to ensure the room does not warm up excessively because of
the heat the instrument radiates to the environment. (Max. permissible
ambient temperature: 40 °C).
With regard to a disturbance in the cooling loop (leakage), the guideline
EN 378 prescribes a certain room space to be available for each kg of
refrigerant.
> For 0.48 kg of refrigerant R404A, a room space of 1 m3 is required.
Example: model FL2506 with 1.5 kg filling quantity of
refrigerant R404A = 3,13 m3volume
Rear view Example: FL2503
•Connect the tubings for cooling the external system to
the pump connectors M16x1 for feed and return (14)
on the rear of the recirculating cooler.
– Return - Feed
•Connect a piece of tubing to the overflow connector
(15) and drain into a suitable vessel, which always has
to be placed lower thant the exit „Overflow“.
•Turn the adjusting valve (13) counter-clockwise to set
the lowest manometric pressure.
•Do not set up the unit in the immediate vicinity of heat
sources and do not expose to sun light.
•Before operating the unit after transport, wait about
one hour after setting it up. This will allow any oil that
has accumulated laterally during transport to flow back
down thus ensuring maximum cooling performance of
the compressor.
IN OUT
min

14
IN
OUT
12 mm inner dia.
Example:
PVC-tubing
•Only water cooled models - FLW:
Ensure circulation of cooling water by connecting the
tubing to cooling water inlet (IN)and outlet (OUT) on
the rear (18) of the recirculating cooler.
Cooling water see page 11.
Cooling water connectors G3/4" external thread
Tubing 12 mm inner dia. tubing
IN Cooling water inlet
OUT Cooling water outlet
Even high quality heat exchangers as they are installed in our equipment can be
damaged by unsuitable cooling water.
The quality of the cooling water depends on the local conditions.
The heat exchanger may become leaky due to corrosion or it may become clogged due
to particulate matter
Notice: Cooling water circuit
Risk of oil leaking from the cooling circuit (compressor) of the recirculating cooler into
the cooling water in case of a fault in the circuit!
Observe the laws and regulations of the water distribution company valid in the location
where the unit is operated.
Caution: Pump pressure
•Determine and check the max. admissible pressure for the external circuit before
putting the unit into operation. The max. pressure is determined by the weakest
element in the circuit (e. g. glass equipment).
•Securely attach all tubing to prevent slipping.
Notice: Flood hazard!.
In case the system to be cooled is located at a higher level than the recirculating
cooler, take note of bath liquid flowing back when the unit is switched off.
Return flow safety device
Should the filling volume of the bath tank not be sufficient, prevent the liquid from
flowing back by using shut-off valves..
Order No. Description Suitable for
8 970 454 Shut-off valve G ¾“ FL(W) 2503/4003
8 970 458 Shut-off valve G 1¼“ FL(W) 2506/4006
The following questions shall help to recognize possible dangers and to reduce the
risks to a minimum.
•Are all tubes and electrical cables connected and installed?
Note:
sharp edges, hot surfaces in operation, moving machine parts, etc.
•What to do when a dangerous substance was spilled on or in the unit?
Before starting to work, obtain information concerning the substance and determine
the method of decontamination.

15
6.1. Tubing
Caution:
•Employ suitable connecting tubing.
•Make sure that the tubing is securely attached.
•Avoid sharp bends in the tubing, and maintain a sufficient distance from
surrounding walls.
•Regularly check the tubing for material defects (e.g. for cracks).
•Preventive maintenance: Replace the tubing from time to time.
Recommended tubing:
Order No. Description Suitable for
8930319 1 m Reinforced tubing 12 mm inner dia. (-40 ... +120°C) FL(W) 2503/4003
8930325 1 m Reinforced tubing 1“ inner dia. (-40 ... +120°C) FL(W) 2506/4006
Tubing insulation
8930419 1 m Insulation, 29 mm inner dia. Reinforced tubing ¾“ inner dia.
8930425 1 m Insulation, 35 mm inner dia. Reinforced tubing 1“ inner dia.
Tube clamps
8970483 2 Tube clamps, size 4 Reinforced tubing ¾“ inner dia.
8970484 2 Tube clamps, size 5 Reinforced tubing 1“ inner dia.

16
7. Operating controls and functional elements
Example: FL25xx Front view Rear view
RS23
2
A
LARM
°C
FL2506
12
3
4
5
6
7
8
9
11
10a
IN OUT
IN
OUT
13
14
15
16
17
18
10b
Draufsicht
4
12
°C
Push
Push
4Protection lid for fill in opening
12 Protection lid for storing place of
operating manual
Lifting device for transportation by crane
1 ON
Mains power switch

17
2.0 Keypad, spash-water protected
2.1 Edit keys (set point increase or decrease)
2.2 Enter key Store set point value / parameter
3.0 Indication
3.1
°C
LED temperature display
3.2 Control indicator – Cooling
3.3
Control indicator – Alarm
4 Protection lid for fill in opening
5 Feed pressure indication: Manometer
6
RS232
Interface RS232: remote control via personal computer
7
Alarm output (for external alarm signal)
8 Filling level indication
9 Drain tap with drain port
10a
10b
Castor with brake (at the front)
Castor without brake (at the back)
11 Venting grid, removable
12 Protection lid for storing place of operating manual
13 Feed pressure adjusting valve
14
Pump connector OUT – pressure pump
Pump connector IN– Return
FL/FLW2503 G ¾“ außen
FL/FLW4003 G ¾“ außen
FL/FLW2506 G 1¼“
FL/FLW4006 G 1¼“
15
Overflow connector
16
F1, F2, F3, F4
Mains circuit breakers (resettable) FL250x
2 Mains circuit breakers (resettable) 4 A (for Electronics)
2 Mains circuit breakers (resettable) 10 A (for Pump motor)
16
0
1
F1, F2, F3, F4
Mains circuit breakers (resettable) FL400x
1 Motor protection circuit breaker for compressor motor
2 Mains circuit breakers (resettable) 4 A (for Electronics)
2 Mains circuit breakers (resettable) 10 A (for Pump motor)
17 Mains power cable with plug
18
IN
OUT
Only water cooled models
IN Cooling water inlet
OUT Cooling water outlet
G3/4" external thread
12 mm inner dia. tubing

18
8. Operating procedures
8.1. Bath fluids
Caution:
No liability for use of other bath liquids!
Please contact JULABO before using other than recommended bath fluids. JULABO
takes no responsibility for damages caused by the selection of an unsuitable bath fluid
Do not use alcohols.
Water:
The quality of water depends on local conditions.
•Due to the high concentration of lime, hard water is not suitable for temperature
control because it leads to calcification in the bath.
•Ferrous water can cause corrosion - even on stainless steel.
•Chloric water can cause pitting corrosion.
•Distilled and deionized water is unsuitable. Their special properties cause corrosion
in the bath, even in stainless steel.
Water: - No liablity for use with water.
Danger of freezing at working temperatures <5 °C.
Mixture water -glycol:
Strictly observe the safety data and handling instructions from the manufacturer.
The proportion of water might evaporate by and by. Check the mixing ratio regularly and
refill water if necessary.
Recommended bath fluids:
Bath fluids Temperature range
Julabo Thermal G -30 °C ... 80 °C
mixture water/glycol (50:50) -30 °C ... 50 °C
soft/decalcified water +5 °C ... 80 °C
Order No. Desription Quantity
8 940 124
8 940 125
JULABO Thermal G
JULABO Thermal G
10 liters
5 liters
8.2. Power connection
Caution:
•Only connect the unit to a power socket with earthing contact (PE – protective earth)!
•The power supply plug serves as safe disconnecting device from the line and must
be always freely accessible.
•Never operate equipment with damaged mains power cables.
•Regularly check the mains power cables for material defects (e.g. for cracks).
•We disclaim all liability for damage caused by incorrect line voltages!
Recommendation in case of single-phase current supply (e.g. FL250x):
The safety cutouts of the house wiring should have the trait „C“ (C16A).
Check to make sure that the line voltage matches the supply voltage specified on the
identification plate.

19
8.3. Filling
Notice:
Risk of injury for hands. Close cover carefully.
Top view
°C
Push
Push
Take care that no liquid enters the interior of the circulating
cooler.
LConnect the tubing from the external system to the pump
connectors and check for leaks
Respect instructions from page 13 to page 15!
LCheck to make sure that the drain tap (9) is closed.
•Unlock and open lid of fill in opening (4) by slightly
pushing.
•Fill in tempering fluid up to marking „H“ of the filling level
indicator.
H
L
•Turn the mains switch (1) on (Switching on - see page 19)
•Switch on unit. To do so press button for approx. 4 seconds.
•Tempering fluid is pumped into the externally connected system.
Refill fluid up to marking „H“.
•The recirculating cooler is ready for operation.
8.4. Switching on / Start - Stop
ON



Switching on:
The recirculating cooler is turned on and off with the mains switch.
The unit performs a self-test. All segments of the 4-digit LED
temperature DISPLAY and all indicator lights will illuminate
(as illustrated on the left).
Then the software version and the type of unit is indicated.
Examples: (v 1.02) (FL2506)
The display "OFF" indicates the unit is ready to operate (standby
mode).
Start: Press enter for about 4 seconds.
The LED temperature DISPLAY indicates the actual bath
temperature.
Stop: 1. Press enter for about 4 seconds.
2. Wait until the LED display stops blinking!
3. Turn the unit off with the mains power switch.

20
8.5. Setting the feed pressure
max.
Set the max. permissible feed pressure (example: 2 bar) by slowly
closing the adjusting valve (13) on the rear and looking at the
manometer (5).
LThe max. pressure is determined by the weakest element in the
circuit (e. g. glass equipment).
8.6. Setting the temperatures
Factory setting: 25 °C
LSetting can be carried out in the start/stop condition.
1. Press one of the keys for a short moment.
The setpoint value instead of the actual value is indicated on the
display for about 8 seconds.
The value can now be changed.
2. Change value:
Press to set a higher value.
Press to set a lower value.
Keep the keys depressed for the value to change fast.
3. Press enter to store the value.
8.7. AUTOSTART ON / OFF
The recirculating cooler has been configured and supplied by JULABO
according to N.A.M.U.R. recommendations. This means for the start
mode, that the unit must enter a safe operating state after a power
failure (non-automatic start mode). This safe operating state is
indicated by „OFF“ on the LED temperature display. A complete
shutdown of the main functional elements such as compressor and
circulating pump is effected simultaneously.
Should such a safety standard not be required, the AUTOSTART
function (automatic start mode) may be activated, thus allowing the
start of the circulator directly by pressing the mains power switch.
Keep depressed enter and
turn on the unit with the mains power switch.
For a short while the LED DISPLAY indicates the effective start mode:
AUTOSTART on. AUTOSTART off.
Warning:
For supervised or unsupervised operation with the AUTOSTART function, avoid any
hazardous situation to persons or property.
The circulator does no longer conform to N.A.M.U.R. recommendations.