Water Baths

Water baths are used in industrial clinical laboratories, academic facilities, government research laboratories environmental applications as well as food technology and wastewater plants. Because water retains heat so well, using water baths was one of the very first means of incubation. Applications include sample thawing, bacteriological examinations, warming reagents, coliform determinations and microbiological assays.

The first thing to consider when purchasing a water bath is the electronics. Digital control systems provide greater temperature uniformity, stability and control. Constanttemperature digital water baths are suited to a host of applications, including bacteriological examinations, food processing/QC procedures and microbiology assays, just to name a few.

Analog systems offer easy-to-use control and are best suited to fixed set-point applications.

Most general laboratory water baths go from ambient temperatures of + 5°C to 99.9°C, with temperature uniformity as tight as ± 0.2°C at 37°C. Many vendors offer temperature preset buttons for quick selection of frequently used temperature set points.

Choosing the right size water bath depends on the volume and size of samples. Water bath sizes can range from 1.5 to 43 liters. To compare different bath volumes, it is best to compare internal tank dimensions.

If there is concern with outside contaminants, it is important to consider a water bath cover. Clear covers allow researchers to see inside. Attached covers eliminate problems with condensation, and gabled covers accommodate glassware of varying heights and permit easy loading and removal of samples. Some manufacturers provide hinged covers that stay open 90 degrees or remove completely. Others offer lid fins that protect hands from hot vapors. Covers are also essential if the lab is operating the water bath above 60ºC, in order to maintain temperature.

Rounded, seamless stainless steel reservoir construction resists rust, chemical damage and contamination. An epoxy-powder-coated exterior simplifies cleanup. The exterior also needs to remain cool, to prevent accidental burns even after extended use.

Safety features may include secondary thermostats that automatically disconnect heater power should the bath temperature get too high or the liquid level drop too low, as well as alarm indicators.

Non-contact recessed heating elements, which specifically curtail element burnout and eliminate tank hot spots, are also available.

Grant Instruments

Thermostatically controlled low-temperature baths and circulators are suited to routine applications as well as spectrometry, viscometry, refractometry and electrophoresis. A choice of four thermostatic controllers and five refrigeration units provides a cost-effective system to meet specific application requirements. Each unit is suitable for either open- or closed-loop circulation. Low-temperature baths and circulators offer ease of operationand low maintenance. Robust, durable construction ensures a long-term low cost of ownership.

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PolyScience

These general-purpose water baths are equipped with sensitive microprocessor-based PID controllers that maintain bath temperatures from ambient +5° to 100°C with ±0.1° precision and ±0.2°C uniformity. They are available with 2-, 5-, 10-, 20- or 28-liter single-chamber reservoirs. They also feature digital temperature readout, one-touch set-point recall, and three user-defined temperature preset buttons for quick selection of frequently used temperature set points. Bath temperature can be displayed in either °C or °F. For added operational convenience, all models include a steeply gabled tilting cover that accommodates glassware of varying heights and permits easy loading and removal of samples while allowing condensate to drain neatly back into the bath. A front-panel lockout prevents inadvertent temperature set-point changes and redundant safety thermostats guard against bath overheating.

www.polyscience.com

Julabo

TW Series water baths feature microprocessor technology and a temperature stability of ±0.2°C at a working temperature range of +20 to +99.9°C. The baths are suitable for simple routine and complex applications. There is overall splash-water protection and a keypad for temperature settings with LED temperature indication. Sensitive samples that require a controlled environment can be protected by features such as dry-running, optical and audible warning, and shut-off features. The TW Series includes four models with filling volumes from 2 to 22 liters as well as a wide range of accessories.

www.julabo.com

Fisher Scientific

Fisher Scientific Isotemp® programmable, digital, dual-temperature control baths are suited for industrial, clinical, pharmaceutical or biomedical procedures. They provide a temperature range from ambient to 100°C. Microprocessor PID control provides ±0.24°C uniformity, ±0.5°C accuracy and stability at 37°C. Display shows °C or °F and can be read from across the room. Low-profile front-panel controls provide easy access and safer operation, while dual thermostats guard against thermal runaway. Hinged acrylic or stainless-steel gable covers have fins that keep hands away from hot vapors. Covers stayopen at 90° or, with quick-release hinge, lift off completely for use with large glassware. Heating elements will not burn out if bath accidentally runs dry. The corrosion-resistant exterior features a tough, easy-to-clean acrylic enamel coating and a temperature-resistant plastic rim that insulates, resists leaks, keeps its shape, and won’t dry out or crack like caulked seals.

www.fishersci.com