LAUDA Loop L 250 Circulation Thermostat, 4 to 80 °C, 250 Watt Cooling Capacity, L000580

If the external circuit requires more heating and cooling capacity than a small benchtop unit can provide, without the need for a large compressor unit with its own refrigerant circuit, the LAUDA Loop L 250 is suitable. This thermoelectric circulation thermostat covers the same working temperature range of 4 to 80 °C as the smaller L 100, but delivers 250 watts of cooling capacity at 20 °C and, if required, up to 0.4 kilowatts of heating power. This allows even larger external volumes or multiple loads on a single circuit to be maintained at a stable temperature.

More power with the same operating concept

Operation and connection technology are the same as for the L 100: a graphical OLED display, plain-text menu, three-button control and an RS232 interface for connection to a higher-level control system. The difference lies in the performance class. As with the smaller model, the internal pump delivers up to 3 litres per minute at a maximum of 0.8 bar, whilst the bath’s maximum capacity is slightly higher at 0.32 litres. Anyone already using an L 100 who switches to the L 250 will therefore not need to familiarise themselves with a new system.

Refrigerant-free even in the larger model

The L 250 also uses thermoelectric cooling via Peltier elements and requires no refrigerant circuit. As with the smaller model, the sound pressure level is 57 dB(A) and the maximum power consumption is 0.4 kilowatts. Measuring 261 x 368 x 312 millimetres and weighing 12 kilograms, the unit is significantly larger than the L 100, but remains compact enough for a unit in this performance class to be installed directly next to the load.

Installation and mains connection

The L 250 is also 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. A mains cable with an angled Schuko plug is supplied as standard; for export, LAUDA offers further plug variants under their own order numbers, for example for the UK, Australia, North America or Brazil. If required, we will clarify which variant is suitable for the respective target market before the order is placed.

Typical applications

With its higher heating and cooling capacity, the Loop L 250 is suitable for tasks that go beyond a single small measuring cell:

• Temperature control of larger double-jacketed reactors and stirred tanks
• Simultaneous supply to several smaller external loads on a single circuit
• Applications with varying heating and cooling capacity requirements within the same process
• Continuous operation in laboratory environments without a separate refrigeration system

Selection guide: which Loop is right for you

If the cooling capacity of the L 250 is insufficient, or if a significantly wider temperature range down to sub-zero temperatures is required, the compressor-based LAUDA Alpha RA 8, LAUDA Alpha RA 12 and LAUDA Alpha RA 24 cooling thermostats are the more suitable choice. For smaller external loads with lower power requirements, the more compact LAUDA Loop L 100 is often sufficient.

Technical details

Scope of delivery

• LAUDA Loop L 250 circulation thermostat, order number L000580
• 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.

Like the smaller L 100, the Loop L 250 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 also available as an accessory for the Loop L 250, compatible with the quick-connect couplings on the supply and return lines. If you also require a different mains plug variant for export or a different temperature-control fluid, please contact our procurement service, which will put together the appropriate accessories for you.