Humid air can condense enough water do damage the electrical circuitry. At least once a year, replace the desiccant located in the pressure case or the external battery canister. You may wish to replace the desiccant bag more regularly if the instrument is exposed to multiple significant changes in temperature (e.g. from a hot/humid surface environment to cool water). If the instrument is opened more regularly throughout the year, it is advised to replace the desiccant bag every time the case is open. Refer to the battery installation procedure for instructions on opening the pressure case.
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