Can you change the battery in the chest strap for polar f6

No, mine works fine.

There is a problem with your watch. Send it back to Polar it should still be under warranty.

here is the contact information for sending in.

The S120 is now a fairly old watch. When the function buttons and heart rate cease to function this is generally an indicator that the battery needs to be replaced. The buttons themselves can also become worn out or weak of function, in either case you have a couple of options.

1) send in to a Polar Authorized Service center: This is very important, do not take to a normal watch shop. You need the watch properly resealed and handled correctly as well as you may need parts such as a button return spring they will not have. Plus there is a 90day warranty on Polar's repair. You will also need to send in your chest strap just to make sure that is still functioning properly. Battery repair about $15-, new buttons another $10ish, and a chest strap if needs replacing about $25 or $30-. $50-$60 total if everything needs work, but this is just an estimate.

2) buy a new watch unit. The RS100 (the current replacement) is about $100- and is easier to use with a better chest strap.

If Heart Rate is being displayed on the equipment in the gym, but not your watch, then your chest strap is transmitting fine, but the watch is not recieving the signal.

It is not uncommon that when a battery is changed outside of a polar authorized service center that something can happen to the internal electronics. I would suggest you send the watch into Polar and have them take a look. if you have had the watch less than 2 years they will most likely take it under warranty and correct the issue, at the very least they have equipment to test and diagnose both the watch and strap, although it sounds like your HR strap is fine since you are getting HR on the machines.

This is really easy to do yourself. Get a CR1632 battery, unscrew the four screws on the back (dont tip the watch as there is a small spring in the watch), unclip the metal band holding in the old battery noting the way 'round the battery is in (minus side up), pop in new battery and push clip back down, when re-fitting the back make sure the spring mentioned earlier lines up with the white sticker with a hole in it on the inside of the watch back, screw down the back. After you have re done all your settings you may need to re-aquaint the watch with the strap, to do this put on the watch and strap, set the heart monitoring going, bring the watch up close to the 'Polar' logo on the chest strap until the time is displayed, should now be all set up.

Andy

Check that the case back is on the right way. A spring sticking out of the watch mech needs to line up with a hole in the white sticker on the inside of the case back, I think this is the receiver aerial.

I had the same problem and found that the chest strap wasn't tight enough to get a good reading. If that doesn't work, you might have to send it in to have the battery changed. Search for a Polar authorized service center. It gives you some troubleshooting tips too. Good luck.

Make sure you don't have the battery in upside down. The large outside case of a button cell is the +positive side.

Bring the watch up close to the chest-strap heartrate monitor, and it will automatically display the time. This only works while in exercise mode.

kb

You have to undo strap (bracelet) first. Then undo caseback and then change the battery. If you are not quick enough while doing replacement, resetting will be needed.