LAUDA Loop L 100 Circulation Thermostat, 4 to 80 °C, 120 Watt Cooling Capacity, L000027

Anyone wishing to operate an external circuit at a constant temperature without the space and noise associated with a compressor will find the LAUDA Loop L 100 circulation thermostat to be a compact device for the laboratory bench. It cools and heats thermoelectrically using Peltier elements, covers a working temperature range of 4 to 80 °C and delivers a cooling capacity of 120 watts at 20 °C. For smaller external loads with limited cooling requirements, such as individual double-jacketed vessels or measuring cells, this is generally sufficient, without the need to purchase a larger cooling unit with its own refrigerant circuit.

Cooling without refrigerant

The Loop L 100 operates entirely without refrigerant. Thermoelectric cooling via Peltier elements requires no refrigerant circuit, compressor or condenser, and consequently runs noticeably more quietly and with less vibration than a conventional compressor-based unit in the same performance class. The sound pressure level is 57 dB(A), the power consumption is a maximum of 0.24 kilowatts, and the heating power is a maximum of 0.2 kilowatts. Under partial load, that is, when only a small amount of cooling or heating is required, the power consumption drops accordingly. Weighing 7 kilograms, the unit is also easy to move around.

Operation and connection

A graphical OLED display shows setpoint and actual values in plain text; operation is via three buttons with simple menu navigation. An RS232 interface allows connection to a higher-level control system or a logging system. The supply and return lines are fitted with 1/4-inch quick-connect couplings; the connected external load can be changed without tools. The internal pump delivers up to 3 litres per minute at a maximum pressure of 0.8 bar; the bath’s maximum filling volume is 0.28 litres. The unit operates with non-flammable liquids such as water or water-glycol mixtures.

Installation and mains connection

The Loop L 100 is designed for ambient temperatures of 5 to 40 °C and operates on a mains supply of 100 to 240 volts at 50 or 60 hertz; it can therefore be operated in various mains environments without a voltage converter. A mains cable with an angled Schuko plug is supplied as standard. For export, LAUDA lists further plug variants, for example for the UK, Australia, North America or Brazil, which are listed under separate order numbers. If you require one of these variants, it is best to check with us before placing your order.

Typical applications

As an external temperature control unit, the Loop L 100 is used wherever a compact unit is sufficient:

• Tempering of external double-jacketed vessels and small reaction vessels
• Maintaining a constant temperature on measuring cells, cuvette holders and viscometers
• Continuous operation on small test set-ups without their own refrigeration system
• Laboratory environments where quiet, low-vibration operation is required

Selection guide: which Loop is right for you

If the cooling capacity of the L 100 is insufficient for the external circuit, the LAUDA Loop L 250, with 250 watts and the same operating concept, offers approximately double the capacity. If significantly more cooling capacity is required, for example, for larger external circuits or lower temperatures in the sub-zero range, the compressor-based LAUDA Alpha RA 8, LAUDA Alpha RA 12 and LAUDA Alpha RA 24 cooling thermostats are the more suitable choice.

Technical details

Scope of delivery

• LAUDA Loop L 100 circulation thermostat, order number L000027
• Mains cable with angled Schuko plug (CEE7/7)
• Operating instructions as a PDF download

Regulatory information

This device is an electrical appliance within the meaning of the German Electrical and Electronic Equipment Act (ElektroG). The WEEE registration number of the manufacturer, LAUDA DR. R. WOBSER GMBH & CO. KG, is DE 66424057. Information on the return of old appliances can be found on our Environment and Disposal page.

The Loop L 100 operates using thermoelectric, refrigerant-free cooling technology based on Peltier elements. Labelling in accordance with Regulation (EU) 2024/573 on certain fluorinated greenhouse gases is therefore not required.

Warranty and procurement service

LAUDA DR. R. WOBSER GMBH & CO. KG, Lauda-Königshofen, offers end customers a 5-year ‘Best’ warranty on this unit, effective from the date of delivery. This is subject to registration at lauda.de within three months of delivery and the use of genuine LAUDA temperature control fluids. The warranty covers defects in materials and workmanship. Exclusions include, amongst others, wear parts such as filters and seals, damage caused during transport, damage resulting from unauthorised tampering, as well as cables, plugs, hoses and adaptors. LAUDA’s warranty terms and conditions (as at 03/2025) apply. Your statutory warranty rights remain unaffected.

A silicone hose is available as an accessory for the Loop L 100, compatible with the quick-connect couplings on the supply and return lines. Our procurement service can, if required, put together a selection of suitable hoses, temperature control fluids and other accessories for the unit.