UnionClay manufactures the DLSB recirculating chiller line in 24 standard build variants: 5L to 100L tank volumes, -30°C or -40°C working ranges, and a choice of sealed or non-sealed tank construction. Deep-cold builds extend to -120°C. Every unit carries a PT100 sensor, LCD control and five-way electrical protection.
Two Tank Constructions, One Production Line
Most chiller suppliers list one tank style and stop there. The DLSB line is built around two distinct constructions, and the difference matters more than the glossy photos suggest. The sealed builds use a closed expansion tank between 2L and 35L and pumps rated on the parameter sheets at 20–45 L/min against 20–25 m of head. The non-sealed builds use an open reservoir matching the model number — 5L through 100L — with pumps listed at 10–60 L/min against 6–11 m of head.
Our reading of those pump numbers: pick a sealed DLSB when the coolant loop runs across the lab or up to equipment on a frame — the 20–25 m head exists for exactly that. Pick a non-sealed DLSB when the chiller sits next to the equipment it cools and you want a large open reservoir that is easy to top up and inspect. Both constructions share the same refrigeration logic, sensors and protections.
| Build aspect | Sealed DLSB | Non-sealed DLSB |
|---|---|---|
| Coolant tank | Closed expansion tank, 2L–35L | Open reservoir, 5L–100L |
| Pump flow on parameter sheets | 20–45 L/min | 10–60 L/min |
| Pump head on parameter sheets | 20–25 m | 6–11 m |
| Working ranges offered | -30°C or -40°C to room temperature | -30°C or -40°C to room temperature |
| Sensor and display | PT100, LCD digital button control | PT100, LCD digital button control |
Sealed DLSB Builds: Closed-Loop Parameter Data
The table below is parsed directly from the published parameter sheets on each recirculating chiller product page. Note where the voltage steps from 220V to 380V — the compressor package grows with tank volume and target temperature, so the DLSB-20/40 sealed unit already moves to three-phase power while the -30°C unit of the same volume stays on 220V.
| Model | Working range | Voltage | Total power | Total current | Expansion tank | Pump flow / head |
|---|---|---|---|---|---|---|
| DLSB-5/30 | -30°C to room temp. | 220V, 50Hz | 0.9 kW | 3.3 A | 2L | 20 L/min / 20 m |
| DLSB-5/40 | -40°C to room temp. | 220V, 50Hz | 1 kW | 4.3 A | 2L | 20 L/min / 20 m |
| DLSB-10/30 | -30°C to room temp. | 220V, 50Hz | 1 kW | 4.2 A | 7L | 20 L/min / 20 m |
| DLSB-10/40 | -40°C to room temp. | 220V, 50Hz | 1.4 kW | 5.8 A | 7L | 20 L/min / 20 m |
| DLSB-20/30 | -30°C to room temp. | 220V, 50Hz | 1.4 kW | 5.9 A | 7L | 20 L/min / 20 m |
| DLSB-20/40 | -40°C to room temp. | 380V, 50Hz | 2.5 kW | 4.9 A | 10L | 20 L/min / 20 m |
| DLSB-30/30 | -30°C to room temp. | 220V, 50Hz | 1.7 kW | 7.5 A | 10L | 20 L/min / 20 m |
| DLSB-30/40 | -40°C to room temp. | 380V, 50Hz | 3.3 kW | 6.4 A | 10L | 20 L/min / 20 m |
| DLSB-50/30 | -30°C to room temp. | 380V, 50Hz | 4 kW | 7.9 A | 17L | 20 L/min / 20 m |
| DLSB-50/40 | -40°C to room temp. | 380V, 50Hz | 4.6 kW | 9.3 A | 17L | 20 L/min / 20 m |
| DLSB-100/30 | -30°C to room temp. | 380V, 50Hz | 4.8 kW | 9.8 A | 35L | 45 L/min / 25 m |
| DLSB-100/40 | -40°C to room temp. | 380V, 50Hz | 5.7 kW | 11.3 A | 35L | 45 L/min / 25 m |
Model pages for the smallest and largest sealed builds: DLSB-5/30 sealed und DLSB-100/40 sealed.
Non-Sealed DLSB Builds: Open-Reservoir Parameter Data
The non-sealed line trades pump head for reservoir volume. At the top end, the 100L reservoir units run 4.8 kW at 380V whether you order the -30°C or -40°C range — one of the few points in the line where the two temperature tiers share a power package.
| Model | Working range | Voltage | Total power | Total current | Reservoir | Pump flow / head |
|---|---|---|---|---|---|---|
| DLSB-5/30 | -30°C to room temp. | 220V, 50Hz | 0.58 kW | 2.57 A | 5L | 10 L/min / 7 m |
| DLSB-5/40 | -40°C to room temp. | 220V, 50Hz | 0.9 kW | 3.47 A | 5L | 10 L/min / 7 m |
| DLSB-10/30 | -30°C to room temp. | 220V, 50Hz | 0.85 kW | 3.47 A | 10L | 15 L/min / 8 m |
| DLSB-10/40 | -40°C to room temp. | 220V, 50Hz | 1.2 kW | 5.12 A | 10L | 15 L/min / 8 m |
| DLSB-20/30 | -30°C to room temp. | 220V, 50Hz | 1.3 kW | 5.22 A | 20L | 15 L/min / 8 m |
| DLSB-20/40 | -40°C to room temp. | 380V, 50Hz | 2.5 kW | 4.55 A | 20L | 15 L/min / 8 m |
| DLSB-30/30 | -30°C to room temp. | 220V, 50Hz | 1.8 kW | 6.9 A | 30L | 15 L/min / 8 m |
| DLSB-30/40 | -40°C to room temp. | 380V, 50Hz | 3.2 kW | 6.05 A | 30L | 15 L/min / 8 m |
| DLSB-50/30 | -30°C to room temp. | 380V, 50Hz | 4 kW | 7.7 A | 50L | 60 L/min / 6 m |
| DLSB-50/40 | -40°C to room temp. | 380V, 50Hz | 4.5 kW | 9.5 A | 50L | 60 L/min / 6 m |
| DLSB-100/30 | -30°C to room temp. | 380V, 50Hz | 4.8 kW | 10 A | 100L | 35 L/min / 11 m |
| DLSB-100/40 | -40°C to room temp. | 380V, 50Hz | 4.8 kW | 10 A | 100L | 35 L/min / 11 m |
Compare entry and top builds directly: DLSB-5/30 non-sealed und DLSB-100/30 non-sealed.
Below -40°C: Deep-Cold Builds Down to -120°C
The 24 standard variants stop at -40°C, but the factory does not. The low temperature recirculating chiller family covers five target tiers with closed-circulation, non-volatile coolant loops.
| Spec area | Low-temperature family data |
|---|---|
| Temperature options | -40°C, -60°C, -80°C, -100°C and -120°C |
| Circulation system | Closed circulation, non-volatile coolant loop |
| Cooling type | Air cooling or water cooling |
| Regelung | PID or PLC options by model |
| Typical series | DLSB and DFY low-temperature systems |
If your process needs both heating and cooling from a single circulation unit, the heating and cooling integrated machines are the sister line built in the same plant.
The Equipment These Chillers Keep Cold
Jacketed Reactor Cooling
DLSB units feed the jackets of glass and stainless reactors for exothermic and low-temperature reaction control. See the full reactor range on our chemical reactor manufacturer page.
Rotary Evaporator Condensers
Condenser cooling for solvent recovery is the second most common pairing — a chiller sized to the condenser keeps recovery rates stable when tap water cannot. Browse the rotary evaporator line these units support.
Molecular Distillation Support
Short-path and molecular distillation condensers need steady low-temperature supply; the deep-cold tiers above -80°C and below exist largely for this work.
General Laboratory Process Cooling
Closed-loop cooling for analytical instruments and process skids where a fixed water supply is unavailable or too warm.
Hardware Standards Fitted at the Factory
Some line items repeat across every DLSB parameter sheet because they are fitted as standard, not sold as options: a PT100 temperature sensor, an LCD display with digital button control showing cooling, circulation, set temperature and real-time temperature, and protection against over-pressure, delay, over-current, overheat and leakage. The five-way protection block is the one we would not let a buyer delete even if asked — refrigeration compressors forgive very little. Production and inspection background is documented on the Qualitäts- und Werksseite.
Chiller Sizing Questions, Answered
What is the difference between a sealed and a non-sealed recirculating chiller?
The coolant tank. Sealed DLSB builds use a closed expansion tank (2L–35L) and higher-head pumps of 20–25 m for longer or elevated loops. Non-sealed builds use an open reservoir (5L–100L) with 6–11 m head pumps for equipment sitting close to the chiller.
Will my DLSB chiller run on 220V or 380V?
It depends on the model, not your preference. Builds up to roughly 1.8 kW ship as 220V, 50Hz single-phase; the larger -40°C and 50L/100L builds move to 380V, 50Hz three-phase. Confirm your facility supply before ordering — the voltage is fixed per model on the parameter sheet.
How do I size a chiller for a jacketed glass reactor?
Send the reactor volume, the target jacket temperature, the solvent or medium, and how far the chiller will sit from the reactor. Tank volume should comfortably exceed jacket volume, and loop distance decides whether you need the sealed line’s higher pump head.
Can a DLSB chiller cool a rotary evaporator condenser?
Yes — condenser cooling for rotary evaporators is a standard pairing in the catalog. Smaller sealed or non-sealed 5L–10L units typically handle bench rotovaps; share your flask volume and solvent so the factory can match capacity.
Do you build chillers colder than -40°C?
Yes. The low-temperature family runs -60°C, -80°C, -100°C and -120°C tiers with air- or water-cooled condensing and PID or PLC control by model. These are configured per inquiry rather than picked from the standard 24-variant list.
More general purchasing questions are collected on the UnionClay FAQ page.
Get a Model Match From the Factory
Skip the guesswork: tell us what the chiller must cool, the lowest temperature your process actually touches, and your facility voltage. An engineer will come back with a specific DLSB model and the parameter sheet to verify it — not a generic brochure.
All figures on this page are parsed from the published DLSB and low-temperature chiller parameter sheets in the UnionClay product catalog. Final configuration is confirmed against your application before quotation.