Hand held portable water meter

We have a Global water flow probe for measuring canal flow.  Flow Probe


Battery life is good(this one ran roughly a decade) but when it fails sending the thing in for service to replace the battery is over 1/3 of the cost of a new one.(a bit over $450 for the service to change the battery).   Currently they have a supply shortage and service is impossible. So we replaced the battery instead. The split location is the seam line around head. This one has a short interior flange that sticks down from display side inside the lower half with a bead of sealant around the bottom edge. Because I went looking for tabs to unlatch and there were none I cut part of the flange off while getting this one apart. There are no tabs and no alignment notches in this one so 2 potential strategies to try getting it apart. A really strong twisting motion might separate the cases by breaking the sealant. Alternately I would try gently flexing the plastic of the display side right at the seam line inward with a pair of slip pliers to break the sealant in localized locations. Repeat till worked far enough around to get the sealant loose. The halves separate and 4 screws hold the display to the case housing. Be sure the meter is face down while you do this as there are 4 tiny metal pins that extend exterior buttons to the interior buttons that are incredibly easy to lose. If face down they will stay in their plastic holders. The battery in this one was a solder in that any good electronics person should be able to change with a battery cost of a few bucks(vs over $450 to service it)(freight will cost you far more than the battery) The battery in this one was CR-2354/HFN. Since we needed it fast we subbed with a CR2450 because they are commonly available here and only 10 mA lower max draw. 560 mA max draw original vs 550 mA max draw for the CR 2450.(given how long the battery lasted likely never draws max)  We fudged a holder together with epoxy and part of an edge of a windshield wiper blade that will work for now.  If I had the time I would try ordering a battery holder to solder it in once and then the battery can simply be changed from then on and change to the battery that is common locally.  Should be able to service to change the battery for less than $20 plus labor vs sending it in for over $450.  If I had known what I was getting into without figuring it all out probably less than an hour of labor involved.   As it was exploring how to split the case and hunting batteries locally because of the need to fix fast took about 4 hours.  Still decent wage compared to sending it in for battery replacement.