Replacing a Dacor Dive Computer Battery

Dacor dive computers are designed to be easy to use and maintain. The Nemo Air, Puck and Darwin digital dive computers calculate depth, safe dive time and air consumption and register dive data in a digital log. Dacor is a brand of Mares, and authorized Mares dealers are sources for appropriate replacement parts. Replacing a dive computer can be costly, and a malfunctioning computer underwater is dangerous, as it provides critical data for dive calculations. If you have reservations or problems regarding battery replacement or dive computer functions, seek technical assistance from an authorized service agent.

  1. Considerations

    • All dive computers have batteries that are enclosed in a watertight compartment, containing an O-ring. Before initiating battery replacement, make sure you have the required battery type, replacement O-ring and silicon grease ready so that you can minimize opening the housing, which can wear the threads of the compartment door. Always replace your dive computer battery in a dry location to prevent possible internal corrosion.

      When the battery is changed on a dive computer, previous settings and history are reset. It is not recommended that the battery is changed between dives or during a dive excursion because safe diving calculations are lost (including fly time and nitrogen load). Before removing the battery from your dive computer make sure your dive profile is backed up or record your dive history in your log.

      After battery replacement, check the functions and seal of your dive computer by submerging the unit in a sink or bucket filled with water.

    Universal Battery Replacement

    • The Nemo Air and Puck dive computers use a lithium CR 2450 battery. The Darwin uses AA batteries. The battery compartment is located on the back of the unit and the waterproof door can be opened by using a coin to turn the slot counter-clockwise to align the battery icons. An O-ring provides a water-tight gasket for the compartment, and upon release of the battery door this ring may be ejected for replacement.

      Remove the existing battery and take note of the orientation of the battery polarity. Clean the battery compartment, taking care to use a dry cloth and ensuring that no dust or fine particles may obstruct the door. Insert your replacement battery, apply a fine layer of silicon grease to your O-ring and insert the ring into the outer groove. Check that no fine particles, dust or hair are attached to the O-ring before positioning your battery cover.

      Align the battery door to match the "Open" icons on the back of the unit. Gently press the door to create a seal before using a coin in the slot to slide the door clockwise to lock. If the door does not lie flush to the back of the unit or if you experience difficulty turning the door to lock, don't force the door closed because this signifies a misalignment or obstruction. Open the cover and recheck the battery and O-ring before attempting to lock the cover.