The battery in my heart rate monitor is weak, so I sent it off for replacement. Technically, it is the receiver (a.k.a. the watch part) battery that is weak, although Polar recommends sending in the transmitter (a.k.a. the chest strap) as well, so they can inspect the entire system. The battery in the transmitter is sealed in with no way to get to it, so if that needs replacement, they just send you a new transmitter.
The lady at the UPS store said she would put the watch and strap in a plastic bag, to protect against water. I laughed and told her that ironically, the whole reason I am sending the item to Polar is because the watch is waterproof - only Polar can change the battery without voiding the warranty, due to the seal. I added, I'd pay extra if after wrapping the watch/strap in a bag, UPS would fill the bag with water - then I could attach a note about how irritating it is to mail off my HRM. ;)
If the watch weren't waterproof, I could just go to any place that sells watch batteries and have them do it. But no, I need to mail off my watch/strap, pre-authorize a $59 charge - to be fair to Polar this is the maximum cost, which includes receiver battery replacement and a new coded transmitter - and be without it all for two weeks of more. Great.
I was thinking of getting the
Polar S625X instead, since it has a foot pod which can be used to measure speed and distance. Instead, I might try the Nike SDM Tailwind, which does the same thing (minus the heart rate monitor functions). This would just be a backup for when the Garmin Forerunner doesn't work.