My wife's Omega Constellation, reference 1372.70 required a battery change. So I decided to change the battery myself. The watch. I am sure I will do better as compared to the Guess watch battery change I did some time ago.
The case back, which is of the snap back design. Here you can see the slot to pry open the case back.
The first thing to do is to make the battery change easier. As such there is a need to disconnect the bracelet to allow easy access to the case back.
Make sure you use the right tool to disconnect the bracelet. The bracelet holder and the proper punch.
Again another view of the slot. You can tape the case back, just below the slot if you don't want to damage the case.
The case back removal tool.
The case back removed.
The Omega calibre 1456, with the battery (reference 321). You will need to remove the metal tab (gold colour plate across the battery) to gain access to the battery. It is important to note that the metal tab is under pressure and will 'pop' out. So you will need to hold it in place when you unscrew the screw. Otherwise the plate can 'pop' and you might loose it.
The case back with the green gasket.
The interesting aspect of the gasket is that it is translucent. Cool.
The old battery removed. Remember to use a non-magnetic tweezers to remove the battery.
The movement, minus the battery. Use some Rodico to clean the contacts.
The said metal tab and screw.
The new battery.
Since it is a Swiss watch, I decided to use the same battery as the original, Renata 321.
The battery fitted into the movement.
The metal tab installed. It is a bit difficult to install, but not impossible. Before you install the case back, just check that the watch actually runs. Since the watch does not have a seconds hand, you will need to wait a couple of minutes to make sure the minutes hand move.
The case back installed. Since it is a snap back case back, it was not difficult to install.
The watch all ready to use.