Temperature Humidity Chambers are available from various chamber 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 a number of things to consider amongst which are:
(a) of the chamber|The inside dimensions of the temperature humidity chamber|Minimum Internal Dimensions of Chamber[/spin]. This will be decided by the size of the product to be tested.
(b)Temperature Range required for the test you intend performing. The maximum range of a Temperature Humidity Chamber is normally from -73C to +200C. However, to perform this full range the chamber will need to have two compressors in what is referred to as a cascade refrigeration system. If only a single compressor is used, then a temperature range of down to approximately -35C is possible. Keep in mind 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 offered without any refrigeration at all. The lowest temperatures at which testing can be performed without refrigeration is normally about 12C above ambient.
(c) Humidity Range required for the test you intend performing. Even though most Temperature Humidity Chambers claim that they have a humidity range of 20% to 95%, what is often not taken into account is the temperature range at which these humidity levels can be controlled. For example, at 25C, the lowest humidity obtainable by most chambers with refrigeration will be about 45% (unless a dehumidifier package is installed). At temperatures above 25C, lower humidity levels than 45% can be controlled. Normally graphs are provided by the manufacturer indicating the temperature versus humidity range of the temperature humidity chamber.
(d) Water Recycling System - If no drain is available to drain the excess water used to create the humidity, one should consider a water recycling system consisting of a water storage container, recycling pump and demineralizer cartridge. This will recycle the water so that a drain is not required. Remember, demineralized water should be used for Temperature Humidity Chambers, not deionized water which can harm the interior of the chamber (usually stainless steel) and other components!
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 require more information, 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
written by DavePF