Posted By Ron Hunter
You could consider methods or improvements to minimise moisture entering the chambers in the first place by (e.g. sealing items prior to storage, fitting an airlock, dehumidifier/air drying systems, etc.. Depends on how much of an inconvenience this build up removal causes you I suppose?

Posted By Descarte
depending on the size and nature of the rooms could they not be manually removed? Either physically or by using a electrical metal heated scraped?

Obviously prevention sounds better than cure

Posted By Bill Elliott
Steve - you don't say what use the storage is put to, but working on the basis that it is food I would agree with earlier posters that prevention is better than trying to manually chip off build up. However if it is food storage I would be a little worried if the operating temperature of the storage was -18 to -20C as this may not produce an adequate product temperature. It is the temperature of the product that it important and to acheive -18C a cabinet temperature of -20 to -25C would be expected. The defrost should not significantly raise the cabinet temperature to the extent that ice builds up and maybe, if your plant has auto defrost there is a malfunction in the timing. Generally modern plant incorporates automatic defrost cycles that prevent ice build up and if ice is building up there is moisture getting in somewhere. Using impact tools to remove ice cannot be doing the structure of the storage much good either.