Polar H9 draining batteries for fun

Equipment
1

Morning All (UK time)

Have a Polar H9 that is around 2 years old.

I tend to replace the strap every year & wash them once a week (Have a new strap ready to go on for 2025)

Previously the unit has used roughly one battery each year (Energizer Lithium CR2025)

Just before Christmas, the unit started reporting low HR values whilst on TR/Zwift via ANT+. Ive seen that before when the battery is going low so swapped out the battery and all was fixed. Fast forward 2 weeks (New year) and its doing it again. Thought it could be an already discharged battery (pulled out of a blister pack so I know its new) so tried another one, so once again fixed.

Hopped on the bike last night and this time, the unit connects to Zwift (ANT+) but shows a HR of zero. Opened TR & connected via BTE, however connection would not hold for more than a second or so before dropping off. Installed Polar Beat app to check status and whilst it can see the monitor, it could not form a connection via BTE.

Put another new battery in & once again it works fine.

The unit is always dried & disconnected from the strap when not in use.

All I can think of is either the unit is now faulty & is burning through batteries for fun, or the pack of batteries are discharged (The pack states a 10 year shelf life and was bought last year).

For now ive kept the previous discharged battery, the one that stopped working last night & the new one. Ive also removed the battery from the unit until I do some voltage checks with a meter on all three batteries to see whether the batteries are coming out the pack pre-discharged.

Has anybody else experienced similar with the H9 & did they find a fix ?

Cheers

2

You seem to be doing all the right things :thinking:

Maybe try a reset?

3 Likes
3

When it wouldnt connect to the Polar Beat app whilst being visible, I tried removing the battery and holding the two metal studs with my fingers for ten seconds last night. I believe this is Polars standard procedure for resetting, however afterwards is continued to do the same available but wont connect faff.

New battery seemed to do the trick.

4

Are you using the same brand of battery?

5

All have been Energizer Lithium CR2025 from the same blister pack of 4.

I cant remember the brand of battery that came with the HR monitor originally & used in year 1

6

It might be worth reaching out to Polar Support about this issue if you haven’t already – they should be able to help you out or perhaps give you a replacement HR monitor if necessary!

1 Like
7

My Polar H10 seems to go through phases of burning through batteries. All I can think is that it must be trying to/be connected to something even though I disconnect after every use?

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8

Bizarrely I found mine lasted better if the disconnected pod was stored studs up rather than studs down :neutral_face:

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9

I do this as well

10

Cant say ive been paying attention to orientation when not in use but anything is worth a try :grin: