Lauda A 6, A 12, A 24, RA 8, RA 12 User guide

Operating instructions

Alpha

Immersion Thermostat
A

Heating Thermostats
A 6, A 12, A 24

Cooling Thermostats
RA 8, RA 12, RA 24

Read the instructions prior to performing any task!

2 / 52 Alpha 7/2022

Manufacturer
LAUDA DR. R. WOBSER GMBH & CO. KG
Laudaplatz 1
97922 Lauda-Königshofen
Germany
Telephone: [phone]
Fax: [phone]
E-mail [e-mail]
Internet http://www.lauda.de

Q4WA-E_13-004-EN English
Translation of the original operating instructions

Release 7/2022 M
replaces release 12/2022 L, 09/2020 j, 08/2020i

7/2022 Alpha 3 / 52

Prefixed safety notes

Before operating the equipment please read carefully all the instructions and safety notes. If you
have any questions please phone us!

Follow the instructions on setting up, operation etc. This is the only way to avoid incorrect opera­tion of the equipment and to ensure full warranty protection.

 Transport the equipment with care!

Cooling thermostats may NEVER be overturned nor put upside down!

 Equipment and its internal parts can be damaged:

 by dropping,
 by shock.

 Equipment must be operated only by technically qualified personnel!

 Never operate the equipment without a proper heat transfer liquid!
 Never operate the equipment without sufficient water or heat transfer liquid level!

 Do not start up the equipment, if:

 it is damaged or leaking,
 the supply cable is damaged.

 Switch off the equipment and pull out the mains plug for:

 servicing or repair,
 before moving the equipment!

 Drain the bath before moving the equipment!

 Have the equipment serviced or repaired by properly qualified personnel only!

 The device may only be used in the following areas:

 Production, quality assurance, research and development in an industrial environment.

The Operating Instructions include additional safety notes which are identified by a triangle with an exclamation
mark. Carefully read the instructions and follow them accurately! Disregarding the instructions may have serious
consequences, such as damage to the equipment, damage to property or injury to personnel.

Product specifications are subject to change without notice!

4 / 52 Alpha 7/2022

Table of content

Prefixed safety notes ..................................................................................................................................................................... 3

1 SAFETY NOTES............................................................................................................................................................................ 6

1.1 GENERAL SAFETY NOTES ....................................................................................................................................................... 6

1.2 OTHER SAFETY NOTES ........................................................................................................................................................... 7

2 BRIEF OPERATING INSTRUCTIONS .................................................................................................................................... 8

3 CONTROL AND FUNCTIONAL ELEMENTS .................................................................................................................... 10

4 UNIT DESCRIPTION ............................................................................................................................................................... 15

4.1 ENVIRONMENTAL CONDITIONS ......................................................................................................................................... 15

4.2 TYPES OF UNIT ..................................................................................................................................................................... 15

4.3 BATHS .................................................................................................................................................................................. 15

4.4 PUMP ................................................................................................................................................................................... 15

4.5 MATERIALS ........................................................................................................................................................................... 16

4.6 TEMPERATURE INDICATION, CONTROL AND SAFETY CIRCUIT .......................................................................................... 16

4.7 REFRIGERATION SYSTEM .................................................................................................................................................... 16

4.8 STANDARD ACCESSORIES................................................................................................................................................... 16

5 UNPACKING ............................................................................................................................................................................. 17

6 PREPARATIONS ...................................................................................................................................................................... 18

6.1 ASSEMBLY AND SETTING UP............................................................................................................................................... 18

6.2 FILLING AND EMPTYING...................................................................................................................................................... 21

6.3 HEAT TRANSFER LIQUIDS AND HOSES ............................................................................................................................... 22

6.4 CONNECTION OF EXTERNAL CIRCUITS .............................................................................................................................. 24

7 STARTING UP ........................................................................................................................................................................... 25

7.1 CONNECTION TO THE SUPPLY ........................................................................................................................................... 25

7.2 SWITCHING ON .................................................................................................................................................................... 25

7.3 GENERAL KEY FUNCTIONS AND PILOT LAMPS ................................................................................................................... 26

7.4 TEMPERATURE SETPOINT SETTING SET............................................................................................................................. 27

7.5 AUTOMATIC SHUTDOWN TIMER ASD ............................................................................................................................... 27

7.6 DEFINING TEMPERATURE LIMITS HI AND LO ................................................................................................................... 28

7.7 REFRIGERATION UNIT SUBMENU COOL ............................................................................................................................ 28

7.8 OFFSET FOR THE INTERNAL TEMPERATURE PROBE CAL ................................................................................................ 29

7.9 RESTORING WORKS SETTINGS DEF ................................................................................................................................... 29

7.10 STANDBY STBY ................................................................................................................................................................... 30

7.11 SAFETY FUNCTIONS ............................................................................................................................................................ 30

7.11.1 Safety functions and removal .................................................................................................................................... 30

7.11.2 Overtemperature and low level protection .............................................................................................................. 31

7.11.3 Overtemperature and low level protection testing .................................................................................................. 31

7/2022 Alpha 5 / 52

Explanation of symbols

Caution

This sign is used where there may be injury to personnel if a
recommendation is not followed accurately or is disregarded.



Note

Here special attention is drawn to some aspect. May include
reference to danger.



Reference

Refers to other information in different sections.

7.11.4 Unlock the overtemperature protection .................................................................................................................. 32

7.11.5 Pump-motor supervision: Overload ......................................................................................................................... 32

7.11.6 Fault list “Alarms and Errors” .................................................................................................................................... 33

8 MAINTENANCE ........................................................................................................................................................................ 34

8.1 CLEANING ............................................................................................................................................................................ 34

8.2 MAINTENANCE .................................................................................................................................................................... 34

8.2.1 Service intervals .......................................................................................................................................................... 34

8.2.2 Testing the heat transfer liquid .................................................................................................................................. 35

8.2.3 Maintenance of the refrigeration unit ....................................................................................................................... 35

8.3 NOTE ON REPAIR ................................................................................................................................................................. 35

8.4 DISPOSAL INFORMATION .................................................................................................................................................... 35

8.4.1 Disposal of refrigerant ................................................................................................................................................ 35

8.4.2 Disposal of packaging ................................................................................................................................................. 35

8.5 ORDERING SPARES AND RATING LABEL ............................................................................................................................. 36

9 ACCESSORIES .......................................................................................................................................................................... 37

10 TECHNICAL DATA AND DIAGRAMS ................................................................................................................................. 39

11 DECLARATION OF CONFORMITY AND PRODUCT RETURNS ................................................................................ 45

12 COPYRIGHT .............................................................................................................................................................................. 48

13 INDEX .......................................................................................................................................................................................... 49

6 / 52 Alpha 7/2022

The units are designed for operation with non-flammable liquids to DIN EN 61010-2-010.

A laboratory thermostat is intended for heating, cooling and pumping liquids according to the needs of the user. This
leads to hazards by high or low temperatures, fire, and the general hazards due to the application of electrical energy.

The user is largely protected through the application of the appropriate standard specifications.

Further hazard sources may arise from the type of material being thermostated, for example by exceeding or undercut­ting certain temperature thresholds or by the fracture of the container and reaction with the heat transfer liquid.
It is not possible to cover all possibilities; they remain largely within the responsibility and the judgement of the operator.

The unit must only be used as intended and as described in these Operating Instructions. This includes operation by suit­ably instructed qualified personnel.

The units are not designed for use under medical conditions according to DIN EN 60601-1 or IEC 601-1!

Classification in accordance with EMC requirements

Unit

Immunity requirements

Emissions class

Customer power supply

Heating and cooling

thermostats

Alpha

Table 1 in accordance

with

DIN EN 61326-1

Emissions Class B

in accordance with

CISPR 11

Only for EU

Domestic connection value ≥

100 A

Table 1 in accordance

with

DIN EN 61326-1

Emissions Class B

in accordance with

CISPR 11

Rest of the world (outside EU)

No limitation

Valid for the USA:
Instructions for Class A digital devices
“This equipment has been tested and found to comply with the limits for Class A digital device, pursuant to Part 15 of
the FCC (Federal Communication Commission) Rules. These limits are designed to provide reasonable protection
against harmful interference when the equipment is operated in a commercial environment. This equipment generates,
uses, and can radiate radio frequency energy and, if not installed and used in accordance with the instruction manual,
may cause harmful interference to radio communications. Operation of this equipment in a residential area is likely to
cause harmful interference in which case the user will be required to correct the interference at his own expense.”
“This device complies with Part 15 of the FCC (Federal Communication Commission) Rules. Operation is subject to
the following two conditions: (1) This device may not cause harmful interference, and (2) this device must accept any
interference received, including interference that may cause undesired operation.”

Valid for Canada:
“This Class A digital apparatus complies with Canadian ICES-003” (ICES = Interference Causing Equipment Stand­ards).
«Cet appareil numérique de la classe A est conforme à la norme NMB-003 du Canada».

1 Safety notes

1.1 General safety notes

7/2022 Alpha 7 / 52

 Check the device carefully for shipping damage before putting into operation. Never start a damaged device!

 Only technically qualified personnel must operate the equipment!

 Connect the unit only to grounded mains power (PE).

 Parts of bath covers (types Alpha RA xx) may reach surface temperatures above 70 °C when operating at higher

temperatures. Take care when touching the device!  Danger of burns!

 Use suitable hoses ( 6.3).

 Protect tubing with hose clips against slipping off. Avoid kinks in the hoses!

 Check hoses from time to time for possible material defects!

 Heat transfer hoses and other hot parts must not come into contact with the supply cable!

 When using the thermostat as circulation thermostat, failure of hoses may lead to leaking of hot heat transfer liquid

and become a danger to personnel and objects.

 When no external consumer is connected to the thermostat the pump outflow must be linked to the return!

 The units are designed for operation with non-flammable liquids to DIN EN 61010-2-010 only.

 Depending on the heat transfer liquid used and the mode of operation it is possible for irritating vapours to be pro-

duced. Ensure appropriate ventilation!

 Always pull out the mains plug before cleaning, maintenance or moving the thermostat!

 Repairs on the control unit and/or the refrigeration system must be carried out by properly qualified personnel only.

 Values for temperature control and indicating accuracy apply under normal conditions according to DIN 12876.

High-frequency electromagnetic fields may under special conditions lead to unfavourable values. This does not af­fect the safety!

1.2 Other safety notes

8 / 52 Alpha 7/2022

This brief instruction shall give you the possibility to operate the unit quickly. For safe operation of the
unit it is absolutely necessary to read all the instructions and safety notes carefully!

1.

Assemble unit and add items as appropriate ( 6).

2.

Fill the unit with corresponding heat transfer liquid.
When starting up the unit, the tubular heater ( 3) has to be covered with liquid! ( 6.2).

Heating and immersion thermostats:
Fill the bath with decalcified water ( 6.3).

Cooling thermostats:
Fill the bath with proper glycol/water mixture ( 6.3).

The units are designed only for operation with non-flammable liquids to DIN EN 61010-2-010.
 Take care of the level of the heat transfer liquid! ( 6.2).

3.

Connect the unit only to a socket with a protective earth (PE) connection.
Compare the information on the rating label with the supply details.

4. 4

.

Switch the unit on with the front switch .

5. 5

.

Now the display shows the current bath temperature, for example

On warning or error message refer section ( 7.11).



The overtemperature cut-out point SAFE is fixed at 105 °C and cannot be changed.
However, you can adjust a minimum and maximum operation temperature of the thermostat ( 7.6).

Bath temperature

2%3

2 Brief operating instructions

7/2022 Alpha 9 / 52

( 7.6)

( 7.8)

Reset to factory default:
Display: dEF
“Enter” pressed for longer than
3 seconds sets back to default:

SEt = 25 °C; Hi = 105 °C;
Lo = -30 °C; Cool= Auto.

( 7.5)

( 7.4)

( 7.7)

Calibrate probe (offset):
Input temperature of reference
thermometer (only offset values
±5 K of actual bath temperature are
accepted).

Display flashes. Set value
with or . Value is accepted
after 4 seconds or proceed immedi­ately with the key: .

( 7.9)

Flashing display “00.00” (preset)
for inactive timer or “hh.mm” for

time to initiate status “Standby”.
Activate timer by setting the Auto
Shut-Down Delay “hh.mm” with

or .
Deactivate timer by setting
“00.00”.
The setting is accepted only by
pressing the key: .

Bath temperature

2%3

Display flashes. Set Setpoint
with or . Value is accepted
after 4 seconds or proceed immedi­ately with the key: .

Maximum Temperature

Hi

Minimum Temperature

Lo

Configure Refrig. System

Cool

Offset probe

CAL

Settings default

dEF

Timer “Auto Shut Down”

ASd

End of menu

End

Setpoint

SEt

Alarm

nnn

Stand By

StbY

Standard

Alarm

Standby (timer event)

( blinking in timer mode)

Configure Refrigeration System
Default: Auto . Possible settings:

on refrigeration on
Auto refrigeration on if needed
oFF refrigeration off

(3 sec.)

10 / 52 Alpha 7/2022

Alpha immersion thermostat

1 Temperature controller with four segment LED display

2 Heater active (yellow LED is lit)
Cooler active (blue LED is lit)
Error signal (red LED is flashing)

3 Menu functions, select and Enter keys

4 Mains switch

5 Screw clamp

6 Tubular heater

7 Temperature probe Pt100

8 Pump outflow with pump outflow reducer

8
1

2

3

4

5

6

7

3 Control and functional elements

7/2022 Alpha 11 / 52

1 Reset button (press only if the display shows SAFE )

2 Cooler cable

3 Rating label

4 Mains cable

5 Screw clamp

1

2 3 4

5

12 / 52 Alpha 7/2022

1 Control head with clamp

2 Bath vessel

3 Four mounting feet

1

2

3

7/2022 Alpha 13 / 52

Alpha Cooling Thermostat

1 Control head

2 Pump connections: return to bath and pump outflow

3 Bath cover

4 Handle on front and back

5 Removable front cover

6 Grille on both sides

7 Four mounting feet

1

2 3 4

5

6

7

14 / 52 Alpha 7/2022

1 Mains cable

2 Rating label

3 Cooler cable

4 Bath drain nozzle

1

2

3

4

7/2022 Alpha 15 / 52

The operation of the thermostats is only allowed under the following conditions as specified in
DIN EN 61010-1 and DIN EN 61010-2-010:

 Indoor use, no outdoor installation.
 Operation of the device up to an altitude of 2000 m above sea level.
 Foundation must be dense, even, non-slippery and non-flammable.
 Keep clear distance ( 6.1).
 Ambient temperature range ( 10).

Use only within this range for an undisturbed operation.

 Mains supply voltage fluctuations ( 10).
 Relative humidity ( 10).
 Transient over voltage according to Installation Categories (Over voltage Categories) II.
 Pollution degree: 2.

The type designation of the Alpha thermostats consists of the letter A or RA (R for identification as low-temperature
unit = cooling thermostat).
The immersion thermostat Alpha (control head) and the type of bath or the refrigeration system respectively.

Examples:

 RA 8 = Immersion thermostat Alpha (control head) and refrigeration system with bath of 8 liters maximum volume.
 A 12 = Control unit Alpha with bath of 12 liters maximum volume.

All units -except the immersion thermostat- provide a stainless steel bath. The last two digits of the model no. corre­spond to the approximate total volume in liter (for example bath RA 24 = approximately 24 liters).

Part of this volume may be used to insert objects. Be precautious to overflow when inserting large volume samples!

For the immersion thermostat the bath volume is limited to 50 liters. The bath has to provide a reliable option to fix the
thermostat clamp (wall thickness 10 – 30 mm).

All units are equipped with a centrifugal immersion pump. The pumps are driven by a shaded pole motor.

The pump outflow connection can be closed without causing any damage to the pump.

The pump flow can be reduced by the pump outflow reducer.

Pump characteristics ( 10 Technical data).

4 Unit description

4.1 Environmental conditions

4.2 Types of unit

4.3 Baths

4.4 Pump

16 / 52 Alpha 7/2022

All parts being exposed to the heat transfer liquid are made of high quality material appropriate to the operating tem­perature. Non-rusting stainless steel and high quality temperature-resistant materials are being used.

The units are equipped with a 4-character LED display, which is used for the display of the measurements and settings,
as well as the operating status. The entry of setpoints and other settings occurs under menu guidance via three keys.

With low level, overtemperature or other alarms the unit switches off the heater on all poles. The pump and the refriger­ating machine are also switched off. Unlocking the protection system ( 7.11.2).

A Pt100 temperature probe detects the outflow temperature in the bath. A high-resolution A/D converter processes
the measurement. Further measurement conditioning occurs using a special control algorithm for controlling the heater
actuator and the refrigeration system.

The refrigeration system consists essentially of a hermetically sealed compressor. Heat of condensation and motor heat
are dissipated by a fan-cooled finned condenser. Fresh air is drawn in at the front of the unit; warmed air is discharged at
the back and to the sides. The ventilation openings must not be restricted in order to ensure proper air circulation.

The compressors are fitted with sensors that responds both to the compressor temperature and to the motor current.

Cooling curves ( 10 Technical data).

All refrigerated RA types are delivered with bath covers and an external circulation set to connect an external circuit.

All heating types A 6, A 12 and A 24 are not supplied with bath covers. Cooling coil, bath cover and external circulation
set can be ordered as accessory ( 9).

A pump outflow reducer avoids to spill over liquid in small baths (A 6, RA 8, A 12, RA 12).

4.5 Materials

4.6 Temperature indication, control and safety circuit

4.7 Refrigeration system

4.8 Standard accessories

7/2022 Alpha 17 / 52

After the unit and accessories have been unpacked they have to be examined for potential transport damages. If there is
any damage visible on the unit, a claim must be filled in writing with the freight forwarder (expeditor); a notification to
the freight forwarder (expeditor) is obligatory so that the shipment can be examined. Please also inform the LAUDA
Service ( 8.5).

Standard accessories:

Catalogue No.

Quantity

Designation

Q4WA-E_13-004-EN

1x

Operating instructions

for all thermostats

UD 425

1x

Screw clamp

for immersion and for heating
thermostats

---

2x

Pump outflow reducer with different hole
sizes (diameter Ø 4.5 or Ø 6.0)

for all thermostats

---

1x

Bath cover

RA (cooling) types only

---

1x

External circulation set

RA (cooling) types only

---

1x

Silicone tube
outlet to inlet (pump connection link)

RA (cooling) types only

EZB 260

Warning label “HOT surface”

for all thermostats

5 Unpacking

18 / 52 Alpha 7/2022

Do not connect with power mains before assembly and setup is complete!!

Place the unit on a flat surface. If necessary, attach the
appropriate pump outflow reducer R onto the pump
nozzle. In small baths use the pressure reducer to pre­vent any splashing of heat transfer liquid.

Immersion/Heating thermostats only:

Fix the clamp at the bottom of the control head by two
screws M4 x 6 A3 (1.4541) ISO 7046 (recessed
countersunk flat heads).

Accessory “cooling coil set”:

Fix the cooling coil set at the bottom of the control head
by means of the two screws (pan head with cross recess).
The cooling coil set belongs to the left side of the head.

R

6 Preparations

6.1 Assembly and Setting Up

7/2022 Alpha 19 / 52

 Hang the thermostat into the bath and fix the clamp

with the knurled screw on the edging of the bath.

 The wall thickness has to be 10 – 30 mm.
 Check for tight fitting!

Carefully attach the immersion thermo­stat to prevent it dropping into the bath.

If this should occur during operation,
never reach into the bath! Withdraw the
mains plug immediately!



Cooling thermostats only

NEVER overturn the unit and never put it upside down!

After transport and before starting up, store it standing in
upright position for two hours if possible.

Do not cover the ventilation openings.

Keep clear distance of at least 40 cm.

Pump connection link (silicone rubber)

Remove the silicone L-tube at the pump housing to improve the
circulation in the bath (only for operation without external consum­er).

L-tube (silicone rubber)
Operation with external consumer

(circulation thermostat ( 6.4))

20 / 52 Alpha 7/2022

 When operating as bath thermostat without external consumer the pump outflow connec-

tion has to be linked to the return. At bath temperature above 70 °C the label “HOT sur­face” supplied must be affixed on the bath at clearly visible position!



 The unit can be operated safely up to an ambient temperature of 40 °C.
 Depending on the loading of the refrigeration system, a temporary shut-off can occur, especially in

case of an ambient temperature of over 35 °C.

 Additionally a higher ambient temperature results in less refrigerating capacity.
 When starting up the refrigeration system after a longer time, it can take up to 30 minutes, de-

pending on the ambient temperature and the unit type, until the nominal refrigerating capacity is
reached.

7/2022 Alpha 21 / 52

Filling

 Close the drain nozzle.
 Fill baths up to a maximum level of 20 mm be-

low the bath bridge.

 Optimum operation at 20 – 40 mm below the

bath bridge.

 Operation is possible down to 70 mm below the

bath bridge.

 Low-level switch-off takes place at approx.

80 mm below the bath bridge!
(Protection testing ( 7.11.3))

Emptying

 Switch off the thermostat, pull out the mains plug!
 Drain the heat transfer liquid through the drain nozzle

 using a flexible tube.



 The units are designed for operation with non-flammable liquids to

DIN EN 61010-2-010  water or glycol/ water mixture.

 When starting up the unit, the tubular heater has to be covered with liquid!
 When connecting an external consumer take care of the heat transfer liquid level for it must not

decrease too much  fill in heat transfer liquid if necessary.

 Do not drain the heat transfer liquid when it is hot or very cold (below 0 °C)!

Bath drain nozzle

6.2 Filling and Emptying

22 / 52 Alpha 7/2022

Approved heat transfer liquids

LAUDA

Designation

Working

temperature

range

Chemical

Designation

Viscosity

kin

Viscosity

kin

@

temperature

Size

Catalogue number

from °C

to °C

mm²/s at 20 °C

mm²/s

5 L

10 L

20 L

Aqua 90 

5 – 90

decalcified water

1

--

LZB 120

LZB 220

LZB 320

Kryo 30 

-30 – 90

Monoethylen-

glycol/water

mixture

4

50 at -25 °C

LZB 109

LZB 209

LZB 309



 At higher temperatures  Evaporation losses  Use bath covers.

Distilled water or fully deionised water must only be used with the addition of 0,1g sodium carbonate
(Na2CO3)/litre water, otherwise  danger of corrosion!

 Water content falls after prolonged operation at higher temperatures  mixture becomes flammable (flash

point 119 °C)  check the mixture ratio with a dosimeter.

Important:
 The units are designed for operation with non-flammable liquids to DIN EN 61010-2-010.

Hoses

Tubing type

di x t

[mm]

Temperature

range °C

Application

Catalogue

number

EPDM-tubing,

non-insulated

9 x 2

10 – 90

for all LAUDA heat transfer liquids

except for Ultra 350 and mineral oils

RKJ 111

EPDM-tubing,

non-insulated

12 x 2

10 – 90

for all LAUDA heat transfer liquids

except for Ultra 350 and mineral oils

RKJ 112

Silicone tubing,

insulated

11

-60 – 100

for all LAUDA heat transfer liquids

except silicone oils

LZS 007

 Protect tubing with hose clips against slipping off!

6.3 Heat transfer liquids and hoses

Safety data sheets are available on request.

7/2022 Alpha 23 / 52



IMPORTANT: There are differences between “water and water”!
 Tap water may be unsuitable for operation due to the calcium carbonate content  risk of calcification of the

stainless steel tank.

 High purity water (from ion exchangers) and distilled or bidistilled water are unsuitable for operation due to the

corrosive properties of these media.  High purity water and distillates are suitable as a medium after the addi­tion of 0.1 g of soda (Na2CO3, sodium carbonate) per liter of water.

LAUDA Alpha thermostats can be operated ideally with LAUDA Aqua 90, available in container sizes of 5, 10 or
20 liters (order number LZB 120, LZB 220 or LZB 320) or with Kryo 30 ( 6.3).



 There is a risk of electrochemical oxidation with the use of racks of non-ferrous metals or non-ferrous metal

samples.

 The LAUDA Alpha thermostat tanks are produced in stainless steel 1.4301 and are accordingly resistant to

mechanical and chemical stresses.

 Due to the different electrochemical potentials of metals electrochemical oxidation may occur in the case of

direct contact between the tank and a rack (for example copper) and the bath may corrode despite the use of
the highest quality materials for the tank.

Avoid the use of this type of rack or the direct contact with this sort of rack or contact with non-ferrous metal sam­ples and the inside of the container. Use original LAUDA stainless steel racks and commercially available racks in
temperature-resistant plastics!

24 / 52 Alpha 7/2022

Operation as circulation thermostat

An external circulation set is installed as standard for cooling
thermostats and available as accessory for immersion and heating
thermostats ( 9).

Assembly for immersion/heating thermostats only:

 Pull out the mains plug!
 Fix the external circulation set at the bottom of the control

head by means of the two screws (pan head with cross re­cess). The external circulation set belongs to the right side of
the head. Connect the pump outlet with the short pump noz­zle using the L-shaped tubing.

 Hang the thermostat into the bath and fix the clamp with the

knurled thumb screw on the edge of the bath.

 When used as circulation thermostat, care for shortest hose

connections with largest inner diameter as possible. This gives
the best flow.

 Connect 9 mm internal diameter tubing from your applica-

tion to the pump connections.

 Pump connections

– return to bath
– pump outflow or pump pressure side.

Pump connection link (silicone rubber)



 If the cross-section of the tubing is too small  temperature drop between bath and external system

due to low flow rate. Increase the bath temperature appropriately.

 Always ensure the maximum possible flow cross-section in the external circuit!

 If the external consumer is placed at a higher level than the thermostat, the pump is stopped

and air penetrates into the thermostating circuit, the external liquid may drain down into the
bath even with a closed system  danger of flooding the thermostat!

 Protect tubing with hose clips against slipping off!!
 When no external consumer is connected to the thermostat, the pump outflow connection

must be linked to the return (pump connection link).

6.4 Connection of external circuits

7/2022 Alpha 25 / 52

Compare the supply voltage with the data on the rating label (rearside on control head).

 Connect the unit only to a grounded mains power socket (PE).
 No warranty when the thermostat is connected to a wrong supply!
 Please make sure that your mains plug is equipped with at least the following safety fuses ( 10).

Power supply Fuse protection

230 V~ 12 A
115 V~ 15 A
100 V~ 15 A

 The start current of the refrigerating machine may exceed those currents distinctly for a short

time.

 Ensure that the unit is filled in accordance with Section ( 6.2).



Note for electric installation on site:

The devices must be protected with a 16 ampere circuit breaker fitted during installation.

Exception: Devices with 13 ampere UK plugs.

 1 s

 Switch on at the mains switch; an acoustic signal is

emitted for about one second.

 Initial check of display and indicators; software version is shown

and the self-test becomes initiated.

 The current bath temperature is shown on the display.



 If necessary add more heat transfer liquid to replace

the amount pumped out to the external circuit.

Bath temperature

2%3

Self-test

8888

7 Starting up

7.1 Connection to the supply

7.2 Switching on

26 / 52 Alpha 7/2022

Enter Key

 Switch from the current bath temperature display to the main

menu;

 activates input, display flashes;
 saves input, display ceases to flash and menu point is left.

/

 Selection of sub menu or setting of numerical values.

Smart Decrement / Increment Button

Speeds up entry by moving the counting position to the left:
 Keys are pressed and held down.

Moves counting position to the right:
 Switching one place to the right occurs by briefly (1 second)

releasing the key, followed by another pressing of the key.

(or 4 sec.)

 Most relevant settings are accepted automatically after ap-

proximately 4 seconds
or

 the setting is accepted immediately pressing the <Enter> key.

and 

 Fault signal: Flashing red Alarm LED and acoustic signal.

 Heating is active when the yellow LED is lit.

 Cooling is active. When the setpoint temperature is lowered, it

may take up to one minute before the blue LED is lit.

7.3 General key functions and pilot lamps

Your Alpha Thermostat is easy to operate.

7/2022 Alpha 27 / 52

 Press key to show SEt (Setpoint).

 Press, display flashes.

or

 Decrement or increment the Temperature Setting ( 7.3).

(Temperature can be set from -25 °C up to 100 °C depending on
limits “Hi” and “Lo”).

Wait 4 seconds or

 Display flashes 4 seconds  new value is automatically accepted, or

value is accepted immediately with <Enter> key.



 When the setpoint temperature is set below the bath temperature, it may take

up to one minute before the blue LED lights.



 Entering value closer than 5 °C to the maximum or minimum temperature limit

(Hi and Lo) are not accepted. A buzzer signal appears. If necessary, first
change the temperature limits ( 7.6).

1x to ASd

 Call the Automatic Shut-Down Timer ASd .

Read Timer:

The display shows… “00.00”: timer not active;

The display shows… “hh.mm” (any value): timer active,

(

hh.mm

minutes remaining to shutdown)

or

Set Timer:

Increment or decrement “hh.mm” (maximum 99:59)

Within 4 seconds after the last change of values confirm the timer value by press­ing <Enter>.

You then proceed to Main Menu “Bath Temperature”: A blinking point indicates
that the timer is running!!



 No change is done without confirmation by <Enter>!
 You can deactivate the timer any time by setting the value “00.00”.

7.4 Temperature setpoint setting SEt

The setpoint is the temperature, which the thermostat should reach and maintain constant.

7.5 Automatic Shutdown Timer ASd

The automatic Shutdown Timer can be activated/deactivated, read out or be set. At shutdown time, the pump, heater
and compressor are deactivated, the display then shows “StbY” ( 7.10).

28 / 52 Alpha 7/2022

2x for Hi

3x for Lo

and 1x

 Select option Hi (maximum temperature),

or option Lo (minimum temperature) using the key .

 Enter the selection

The maximum temperature can be set from 35 °C to 105 °C.
The minimum temperature can be set from -30 °C to 30 °C.

The current temperature limit value is displayed flashing.

or

 Set the required temperature limit.

Wait 4 seconds or

 Display flashes 4 seconds  new value is automatically accepted, or
 By pressing the <Enter> key the value is accepted immediately.

4x to CooL

and 1x

 Call the option CooL.

or

 Configure the refrigeration system with these possible settings:

Auto automatic refrigeration mode;
on refrigeration on duty;
oFF refrigeration out of duty.

 The selected mode is displayed flashing.

Wait 4 seconds or

 Display flashes 4 s  new selection is automatically accepted,

or

 it is immediately accepted with the <Enter> key.

Hi

Lo

7.6 Defining temperature limits Hi and Lo

With this function, it is possible to define a minimum and a maximum temperature in which the thermostat controls. By
reaching the temperature limits, a warning appears. In this way setpoint input can be prevented which may damage the
heat transfer medium or the apparatus. For example, if water is used as the heat transfer liquid, 95 °C would be practi­cable as the maximum temperature and 5 °C as the minimum temperature. The default values are Hi = 105 °C and
Low = -30 °C.

7.7 Refrigeration unit submenu CooL

Menu Cool only with cooling thermostats.

7/2022 Alpha 29 / 52

5x to CAL

and 1x longer than
3 seconds.

 Call the option CAL.

or

 Display flashes. Enter the value of the reference thermometer.
 The selected value is displayed flashing.

Wait 4 seconds or

 Display flashes 4 s  new value is accepted automatically,

or

 value is immediately accepted with the <Enter> key.

If you would like to restore all the works settings except the probe calibrations

CAL…

6x to dEF

and 1x

 call the works settings dEF .
 dEF is flashing.

3 seconds long

 Press <Enter> more than 3 seconds (display flickering).
 After button release the changeover is acknowledged with donE, the unit

returns back to the mode “Bath temperatur”.



 Reset Values: Set = 25 °C, Hi = 105 °C, Lo = -30 °C, Cool = Auto

dEF

7.8 Offset for the internal temperature probe CAL

Keep attention: All change done here cause the loss of factory calibration!

Calibration should only be activated if a sufficiently accurate temperature measurement device is available as reference.

If, during checking with a calibrated reference thermometer, (for example from the LAUDA DigiCal Series), a devia­tion is found, then the offset (i.e. the additive part of the characteristic) of the internal measuring chain can be adjusted
with the following function. The reference thermometer must be dipped into the bath according to the details on the
calibration certificate. Only offset values of ±5 Kelvin are accepted. Switching on the unit, the last used CAL value is
preloaded again.

7.9 Restoring works settings dEF

30 / 52 Alpha 7/2022

 StbY is displayed.
 To switch to menu Setpoint (SEt) press <Enter>.

StbY

7.10 Standby StbY

The status “Standby” follows any automatic Shut-Down procedure. To reactivate the standard operation menu, press
the <Enter> button and for example modify the latest Setpoint.

7.11 Safety functions

7.11.1 Safety functions and removal

Your Alpha Thermostat triggers alarms, warnings or errors as appropriate.
All warnings, alarms or errors are shown on the LED display.

Alarms: Alarms are safety relevant. Components (Pump / Heater / Refrigerating Unit) will be shut down.

Errors: When an error occurs switch off the device. If the error is always present after switching on the device,

please inform the LAUDA Service ( 8.5) or the local service organisation!

Find cause of alarm, warning or error and rectify where necessary. Then press on the control head in order to re­move the message.

Warnings may be ignored by pressing or on the control head.

7/2022 Alpha 31 / 52



The units are designed for operation only with non-flammable liquids to
DIN EN 61010-2-010.

 The overtemperature cut-off point is activated close above 105 °C and can

not be changed.

 

 If the bath temperature rises above the overtemperature cut-off point or the

liquid level is too low ( 6.2):

1. Alarm sounds as dual-tone signal.

2. SAFE for overtemperature cut-off point appears in the display.

3. The red LED above the fault triangle flashes.

 Heater switches off on all poles;
 Pump and refrigerating unit are switched off electronically.

 Rectify cause of fault.
 Wait until the bath temperature has cooled below the cut-off point.

Unlock the thermostat ( 7.11.4).

Therefore:

 Remove the heat transfer liquid of the thermostat ( 6.2).

 Turn on thermostat and set the set temperature to a value a couple degrees

above ambient temperature.

 

 The heater of the thermostat will now start heating. Attention the heater will

get very hot. Don't touch it at any time.

 Wait about 45 seconds until the protection device will shut off the heater and

the pump and the alarm SAFE will appear.

 If it takes more then 45 seconds for the overtemperature protection to get

triggered immediately cut out the power manually and have the equipment
checked by the LAUDA Service or the local service organization.

 Refill the heat transfer liquid ( 6.2).
 Unlock (reset) the alarm ( 7.11.4).
 Shut off the control head and turn it on again. The alarm must have disap-

peared now.

Overtemperature alarm

SAFE

Overtemperature alarm

SAFE

7.11.2 Overtemperature and low level protection

7.11.3 Overtemperature and low level protection testing

Every 6 month or before the unit is running unattended for longer periods this protection should be tested.

32 / 52 Alpha 7/2022

 Switch off the thermostat, pull out the mains plug!
 To unlock the protection, push the reset knob behind the ventila-

tion grille (see arrows). You can use for example a pen.

 Switch on the thermostat.

 

A temperature sensor monitors the pump:

1. Alarm sounds as dual-tone signal for pump-motor overload or blockage.

2. Display of PuP signals blockage.

3. The red LED above the fault triangle flashes.

 Heater switches off on both poles;
 Pump and refrigerating unit are switched off electronically.

 Switch off the thermostat, pull out the mains plug!
 Find the cause of the fault. Perhaps the viscosity of the heat transfer liquid is

too high or the pump is blocked.

 Rectify cause of fault.
 Press the <Enter> key.
 Also press this key if the unit has been switched off in the fault state.

PuP

7.11.4 Unlock the overtemperature protection

7.11.5 Pump-motor supervision: Overload

7/2022 Alpha 33 / 52

Message on display

Meaning

ourt

Bath temperature > overall maximum temperature 110 °C

hEAd

Temperature in control head > 75 °C

SAFE

Low level overheat protection has tripped

PuP

Pump blocked (no rotation)

Hi

Bath temperature > maximum temperature ( 7.6)

Lo

Bath temperature < minimum temperature ( 7.6)

Message on display

Meaning

E001

Sensor Issue (short)

E002

Sensor Issue (open); unexpected sensor value

 If there is any irregularity when testing the safety devices, switch off the unit immediately and

pull out the mains plug!

 Have the unit checked by the LAUDA Service or the local service organisation!
 The heater surface can reach temperatures up to 250 °C when there is not enough liquid in the

bath  Danger of burning injuries. Use only non-flammable liquids, otherwise  Danger of
fire!

7.11.6 Fault list “Alarms and Errors”

Alarms

Errors

34 / 52 Alpha 7/2022

 Before cleaning the unit, pull out the mains plug!
The unit can be cleaned with water adding a few drops of detergent (washing up liquid), using a moist cloth.

 Water/ heat transfer liquid must not enter the control unit!



 Carry out appropriate detoxification if dangerous material has been spilled on or inside the unit.
 Method of cleaning and detoxification are decided by the special knowledge of the user. In case of

doubt please contact the manufacturer.

 Before any maintenance and repair work pull out the mains plug!
 Repairs on the control unit must only be carried out by properly qualified personnel!

If the heat transfer liquid becomes contaminated, it has to be replaced.

System part

Frequency

Comment

Each time of putting into operation and then

Complete device

External condition of the device

Monthly

Heat transfer liquid

Test of the heat transfer liquid

( 8.2.2)

Heat transfer system

Sealing

Daily

External visual inspection

External hoses

Material fatigue

Monthly

External visual inspection

Cooling unit

Condenser cleaning

( 8.2.3)

Cooling thermostat

Electronics

Over temperature protection

( 7.11.3)

Low level protection testing

( 7.11.3)

8 Maintenance

8.1 Cleaning

8.2 Maintenance

8.2.1 Service intervals

7/2022 Alpha 35 / 52

Condenser cleaning

The refrigeration unit operates largely without mainte­nance.

Depending on the ambient dust conditions and the operat­ing time, any dust on the heat exchanger (condenser)
must be removed at intervals of 2 weeks or longer.

This is done after taking off the front grille. Brush off the
condenser and if necessary blow through with compressed
air.

If you need to send in a unit for repair, it is essential to first contact the LAUDA Service ( 8.5).



 If the equipment has to be returned to the factory, please ensure that it is packed carefully and

properly. LAUDA accepts no responsibility for damage due to unsatisfactory packing.

The following applies to Europe: The disposal of the device is regulated by EU Directive 2012/19/EU
(WEEE Waste of Electrical and Electronic Equipment).

The type and filling quantity of the refrigerant can be read on the unit or on the rating plate. Repair and disposal only
through a qualified refrigeration engineer!

The refrigerant must be disposed of in accordance with regulation 2015/2067/EU in combination with regulation
517/2014/EU.

The packaging must be disposed of in accordance with EU Directive 94/62/EC.

8.2.2 Testing the heat transfer liquid

If the heat transfer liquid becomes contaminated, it has to be replaced ( 6.2 and 6.3).

If required, the heat carrier should be checked for capability for use (for example when changing the method of opera­tion), or at least half-yearly. Further use of the heat carrier is only permissible if the inspection indicates this.

The test of the heat transfer liquid should takes place according to DIN 51529; Testing and assessment of used heat transfer media.
Source: VDI 3033; DIN 51529.

8.2.3 Maintenance of the refrigeration unit

8.3 Note on repair

8.4 Disposal information

8.4.1 Disposal of refrigerant

8.4.2 Disposal of packaging

36 / 52 Alpha 7/2022

When ordering spares please quote instrument type and serial number from the rating label. This avoids queries and sup­ply of incorrect items.

Rating label at immersion/heating thermostats

Contact LAUDA Service Constant Temperature Equipment in the following cases:

 In the event of faults on the machine
 For spare part orders
 In the case of questions about the machine

Contact our Sales Department for application-specific questions.

LAUDA Service

Phone: [phone] (English and German)

Fax: +(0)49 9343 503-283

E-mail: [e-mail]

We are available any time for your queries and suggestions!

LAUDA DR. R. WOBSER GMBH & CO. KG

Laudaplatz 1

97922 Lauda-Königshofen

Germany
Phone: [phone]
Fax: [phone]

E-mail: [e-mail]

Internet: http://www.lauda.de/

8.5 Ordering spares and rating label

7/2022 Alpha 37 / 52

Accessories for Class Alpha thermostats

Description

suitable for

Catalogue

number

Cooling coil set

for all heating thermostats

LCZE 004

External circulation set

for all heating thermostats

LCZE 005

Bath cover

A 6

LCZE 006

Bath cover

A 12

LCZE 007

Bath cover

A 24

LCZE 008

Rack for 12 tubes,

d = 20 mm

stainless steel,

180 mm x 60 mm x

80 mm,

-40 – 200 °C

two racks fit in each of A 12

one rack fits in each of RA 12

six racks fit in each of A 24 and RA 24

UE 038

Rack for 90 tubes,

d = 13 mm

PP white,

250 mm x 100 mm

x 65 mm,

0 – 135 °C

two racks fit in each of RA 12

three racks fit in each of A 24 and RA 24

UE 037

Rack for 60 tubes,

d = 16 mm

PP white,

250 mm x 100 mm

x 65 mm,

0 – 135 °C

two racks fit in each of RA 12

three racks fit in each of A 24 and RA 24

UE 042

Rack for 40 tubes,

d = 20 mm

PP white,

250 mm x 100 mm

x 65 mm,

0 – 135 °C

two racks fit in each of RA 12

three racks fit in each of A 24 and RA 24

UE 039

Rack for 24 tubes,

d = 25 mm

PP white,

250 mm x 100 mm

x 65 mm,

0 – 135 °C

two racks fit in each of RA 12

three racks fit in each of A 24 and RA 24

UE 040

Rack for 21 tubes,

d = 30 mm

PP white,

250 mm x 100 mm

x 65 mm,

0 – 135 °C

two racks fit in each of RA 12

three racks fit in each of A 24 and RA 24

UE 041

9 Accessories

38 / 52 Alpha 7/2022

Rack for 90 tubes,

d = 13 mm

PP yellow,

250 mm x 100 mm

x 65 mm,

0 – 135 °C

two racks fit in each of RA 12

three racks fit in each of A 24 and RA 24

UE 043

Rack for 60 tubes,

d = 16 mm

PP yellow,

250 mm x 100 mm

x 65 mm,

0 – 135 °C

two racks fit in each of RA 12

three racks fit in each of A 24 and RA 24

UE 048

Rack for 40 tubes,

d = 20 mm

PP yellow,

250 mm x 100 mm

x 65 mm,

0 – 135 °C

two racks fit in each of RA 12

three racks fit in each of A 24 and RA 24

UE 045

Rack for 24 tubes,

d = 25 mm

PP yellow,

250 mm x 100 mm

x 65 mm,

0 – 135 °C

two racks fit in each of RA 12

three racks fit in each of A 24 and RA 24

UE 046

Rack for 21 tubes,

d = 30 mm

PP yellow,

250 mm x 100 mm

x 65 mm,

0 – 135 °C

two racks fit in each of RA 12

three racks fit in each of A 24 and RA 24

UE 047

All racks are delivered without test tubes.
For further accessories please refer to our Accessories Catalog or contact us directly ( 8.5).

7/2022 Alpha 39 / 52

The figures have been determined according to DIN 12876.

Common technical data of Alpha Thermostats

Ambient temperature range

°C

5 – 40

Humidity Maximum relative humidity 80 % for temperatures up to 31 °C,

decreasing linearly to 50 % relative humidity at 40 °C

Storage temperature range

°C

-50 – 70

Temperature stability at 37 °C

K

±0.05

Display & setting resolution

°C

0.1

Pump type / number of pump steps

--

Pressure pump / 1

Connections for consumers
(accessory)

--­Hose nozzle ½”, 12.7 mm external diameter

Heater power
230 V; 50/60 Hz
115 V; 60 Hz
100 V; 50/60 Hz

kW
kW
kW

1.5

1.15

1.0 ( 7.1)

Least mains fuse protection
230 V~
115 V~
100 V~

A
A
A

12
15
15

Safety Class

---

1/NFL* according to DIN 12876

Protection class

---

Protection class l according to DIN EN 61140; VDE 0140-1

10 Technical data and diagrams

*NFL non-flammable liquids

Product specifications are subject to change without notice!

40 / 52 Alpha 7/2022

Alpha Immersion Thermostat

Working temperature range

°C

25 – 100

Operating temperature range

°C

-25 – 100

Pump flow

L/min

15

Pump pressure

bar

0.2

Bath volume

L

up to 50

Connections for cooling coil (accessory)

---

Hose nozzle 11.7 mm external diameter

Overall dimensions (W x D x H)

mm

125 x 150 x 300

Weight

kg

3.5

Ingress protection rating
IP Code according to IEC 60529

---

IP 20

Power supply

Power consumption

230 V~ ±10 %; 50/60 Hz

kW

1.5

115 V~ ±10 %; 60 Hz

kW

1.2

100 V~ ±10 %; 50/60 Hz

kW

1.0

Product specifications are subject to change without notice

!

7/2022 Alpha 41 / 52

Alpha Heating and Cooling Thermostats

Units

A 6

A 12

A 24

RA 8

RA 12

RA 24

Working temperature range

°C

25 – 100

-25 – 100

Operating temperature range

°C

-25 – 100

-25 – 100

Cooling capacity (eff.),
ethanol @ 20 °C am­bient temperature

20 °C W

225

325

425

10 °C W

190

300

370

0 °C W

160

260

330

-10 °C W

130

210

225

-20 °C W

80

80

80

-25 °C W

30

30

20

Pump flow

L/min

15

Pump pressure

bar

0.2

Bath volume

L

2.5 – 5.5

8 – 12

18 – 25

5 – 7.5

9.5 – 14.5

14 – 22

Bath vessel

---

Inner tank in stainless steel

Housing

---

Powder-coated steel sheet

Feet

---

Four mounting feet

Bath opening (W x D)
with Head

mm

145 x 161

235 x 161

295 x 374

165 x 177

300 x 203

350 x 277

Bath opening (W x D) without
head

mm

145 x 295

235 x 295

295 x 500

Bath depth

mm

150

200

200

160

160

160

Useable bath depth

mm

130

180

180

140

140

140

Height of top edge of bath with­out cover

mm

212

262

262

450

450

450

Overall dimensions
(W x D x H)

mm

181 x 332

x 370

270 x 332

x 420

332 x 535

x 420

235 x 500

x 605

365 x 500

x 605

415 x 605

x 605

Weight

kg

6.2

7.5

10.5

31

37

43

Ingress protection rating IP Code
accord. to IEC 60529

---

IP 20

IP 20

42 / 52 Alpha 7/2022

Power consumption

Power supply

Units

A 6

A 12

A 24

RA 8

RA 12

RA 24

230 V~ ±10 %; 50/60 Hz

kW

1.5

1.5

1.5

230 V~ ±10 %; 50 Hz

kW 1.8

1.8

1.8

220 V~ ±10 %; 60 Hz

kW 1.8

1.8

1.8

115 V~ ±10 %; 60 Hz

kW

1.2

1.2

1.2

1.5

1.5

1.5

100 V~ ±10 %; 50/60 Hz

kW

1.0

1.0

1.0

1.3

1.3

1.3

Units

RA 8

RA 12

RA 24

Refrigerant

---

R-134a

R-134a

R-134a

maximum filling quantity

kg

0.11

0.13

0.17

GWP

(100a)

*

---

1430

1430

1430

CO2 equivalent

t

0.2

0.2

0.2



Global Warming Potential (GWP),
Comparison CO2 = 1,0

* Time span 100 years - according to IPCC IV

Refrigerant and filling quantity

The cooling thermostat contains fluorinated greenhouse gases.

Product specifications are subject to change without notice!

7/2022 Alpha 43 / 52

Pump characteristics Alpha Immersion Thermostat

measured with water

Heating up curves from Alpha A 6, A 12 and A 24 (230 V~)

(@ 230 V~)

44 / 52 Alpha 7/2022

Cooling characteristics Alpha RA 8, RA 12 and RA 24 (230 V~)

(@ 230 V~)

7/2022 Alpha 45 / 52

11 Declaration of Conformity and Product Returns

46 / 52 Alpha 7/2022

7/2022 Alpha 47 / 52

48 / 52 Alpha 7/2022

This manual is protected by copyright and only meant for internal use by purchasers.
The relinquishment of this manual to third parties, copying in any way whatsoever – even in the form of excerpts – and

the utilization and/or conveyance of its content are not allowed, except for internal purposes, without written approval
from the manufacturer.

Violation of this may obligate the violator to the payment of damages. Other claims reserved.
We point out that the designations and brand names of the respective companies used in the manual are generally

subject to trademark, brand and patent protection.

12 Copyright

7/2022 Alpha 49 / 52

13 Index

A

Hi ........................................................................................ 28

Accessories ........................................................................ 37

Standard accessories ..................................................... 17

Alarms ................................................................................. 30

ASd ..................................................................................... 27

Automatic Shutdown Timer .............................................. 27

B

Baths ................................................................................... 15

C

CAL ..................................................................................... 29

Circuit breaker ................................................................... 25

Cleaning ............................................................................. 34

CooL ................................................................................... 28

D

K

Key functions ..................................................................... 26

L

LED signals ......................................................................... 26

Lo ........................................................................................ 28

Low level protection ........................................................... 31

Low level Protection testing .............................................. 31

M

Maintenance ...................................................................... 34

O

Overtemperature cut-off ................................................. 31

Overtemperature protection ............................................ 31

dEF ..................................................................................... 29

Drain nozzle ........................................................................ 21

E

EMC standard DIN EN 61326-1 .................................... 6

Enter Key ........................................................................... 26

Errors .................................................................................. 30

F

Fault list "Alarms and Warnings" ....................................... 33

Filling quantity .................................................................... 42

G

GWP ................................................................................... 42

H

P

Packaging ........................................................................... 35

Personnel, qualified .............................................................. 6

Pump connection link ........................................................ 24

PuP Pump blocked ............................................................ 32

R

Refrigerant ......................................................................... 42

Reset ................................................................................... 32

S

SAFE Overtemperature alarm .......................................... 31

Self-test.............................................................................. 25

Service intervals ................................................................. 34

SEt...................................................................................... 27

Setting of numerical values ............................................... 26

Heat transfer liquid, Testing .............................................. 35

Spares ................................................................................. 36

50 / 52 Alpha 7/2022

Standby .............................................................................. 30

StbY .................................................................................. 30

minimum temperature .................................................. 28

U

T

Temperature

Limit temperature ......................................................... 28

maximum temperature ................................................. 28

UK plugs ............................................................................. 25

W

Warnings ............................................................................ 30

LAUDA DR. R. WOBSER GMBH & CO. KG ◦ Laudaplatz 1 ◦ 97922 Lauda-Königshofen
Telephone: [phone] ◦ Fax: [phone]
E-mail: [e-mail] ◦ Internet: https://www.lauda.de