Temperature Humidity Chambers are available from a number of manufacturers such as Thermotron, Tenney, Espec, Blue M, Despatch, Ransco, TestEquity, Associated Environmental, Bemco, Cincinnati Sub Zero, BMA, Lunaire etc. When buying a Temperature Humidity Chamber, there are numerous items to consider amongst which are:

(a) The internal volume of the temperature humidity chamber|Minimum Internal Dimensions of Chamber[/spin]. This will be determined by the size of the product to be tested.

(b)Temperature Range needed for the test you wish to perform. The maximum range of a Temperature Humidity Chamber is frequently from -73C to +200C. However, to achieve this complete range the chamber will need to have two compressors in what is referred to as a cascade refrigeration system. If only one compressor is used, then a temperature range of down to approximately -35C is possible. Remember though that humidity testing can not be performed below 0C (freezing point) and that any testing below 0C will be possible for temperature only testing (humidity function will be disabled). Temperature Humidity Chambers are also available without any refrigeration at all. The lowest temperatures at which testing can be performed without refrigeration is frequently about 12C above ambient.

(c) Humidity Range needed for the test you wish to perform. Although most Temperature Humidity Chambers claim that they have a humidity range of 20% to 95%, what is often overlooked is the temperature range at which these humidity levels can be achieved. For example, at 25C, the lowest humidity obtainable by most temperature humidity chambers that include refrigeration will be about 45% (unless a dehumidifier package is installed). At temperatures above 25C, lower humidity levels than 45% can be achieved. Manufacturers normally provide graphs showing the temperature versus humidity range of the chamber.

(d) Water Recycling System - If no drain is available to drain the excess water used to create the humidity, you should consider a water recycling system consisting of a water storage container, demineralizer cartridge and recycling pump. This will recycle the water so that a drain is not required. Important - demineralized water should be used for Temperature Humidity Chambers, not deionized water!

This information has been brought to you by LR Environmental Equipment Co. Inc. which carries the largest inventory of Certified Refurbished Environmental Test Chambers and Industrial Ovens in the World.

Should you have any questions, they can be contacted at 800-574-2748. Purchasing Certified Refurbished Temperature Humidity Chamber from a reputable company such as LR Environmental who has been in business for over 40 years can save you a fortune while removing the risks When buying used. WWW.LRE.COM