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How to replace the battery in a Polar F11 Heart Rate Monitor (HRM)

Disclaimer: The user manual for the Polar F11 clearly states to take the HRM to a Polar dealer and have them replace the battery - taking the back off could void your warranty. If you wish to be 100% sure that you maintain the water-resistant seal and do not want to void your warranty - or risk breaking your HRM (certainly a possibility when you take it apart...), take the unit to an authorized Polar dealer and have them replace the battery.

Step 1: Remove the back cover (4 little screws - make sure you have the right size screwdriver or you'll strip them out). Also note that the back has a water-resistant seal - keep this clean and remember that there is always a chance that the seal may be damaged if you do this yourself.
Step 2: Remove the internal unit from the watch casing (it just pulls out).
Step 3: Get something to pry the battery latch tab with (I used another small screwdriver)
Step 4: Take whatever you used to pry the latch tab out with and use it to pry the battery up by placing the device (screwdriver in my case) in the notch above the latch (see picture).
Step 5: Go to Wal-Mart and purchase a new CR2032 watch battery (you may want to do this before hand... I didn't know what battery it used so I had to take it out first) - runs about $3.50.
Step 6: Put the battery back in and put everything back together.
Comments (258) Trackbacks (1)
  1. Maybe this site helps to hard reset the F11:

  2. Any update on the “no heart rate over 10cm distance from transmitter”

    I am having the same issue.


  3. Thanks very much. Just a note to be careful removing the battery latch, step 3, you seemed to jimmy the screwdriver over the plastic tap to pry the metal forward. I went the other way and sheared the plastic tab off!. Also the screws on the cover required a torx 4 insert. We thank you.

  4. in my experience polar sucks

  5. is there any fix if the monitor reads erratic numbers or wont read any at all

  6. Worked for me!! – – Only additional point I would make is that the battery restraining strap and the latch tab at the end is a spring fit. It comes loose more easily if some pressure is employed to push the strap on to the body of the battery when prying the latch.


  7. Hi,
    This is the second time I replace the battery of my Polar F11. The 1st time was everything ok, I had no problem. But on the 2nd time, after I replaced the battery, my Polar stays with the display blank. All butons appears to work (I hear the beeps), but I can’t see anything. I don’t know what happened. I tried the reset (pressing all the keys) and the display shows all numbers e icons, but if I press a button (or after a few seconds), the displays goes blank again. Anyone have any idea of what happened and how to solve?

  8. I just got my old F6 working again, thanks to these instructions and brilliantly helpful close-up photographs.
    Thanks for the help!

  9. you don’t say what type of screwdriver! The screws are very specific and none in my set works no matter which size! Help appreciated.

  10. Very helpful Thank you so much. Without your help I would have probably screwed this thing up.

  11. Hallo, sehr interessanter Beitrag, siehe auch REALASH ist die unbestrittene N.
    1 in der Welt der Wimper Conditioner – von echten Frauen, die von Dermatologen getestet, von Bloggern aus aller Welt zu empfehlen.

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