Fenix 6 wrist HR massively inaccurate again after v15.20 upgrade

Same behaviour, starts out normal and then just goes crazy and I end up overreaching, thanks to abnormal HR. Bring back version 13.10!!

A bit more info into what I've found--- I honestly can't say I can correlate to 15.20 or not.  I've only had the watch since mid Jan 2021. 

Anyway I've only seen the high HR spike when I'm on the elliptical and I'm using the cardio app, not with the elliptical app. When it happens it's very dramatic and occurred only a couple mins into the workout.  Today I was using the Cardio app while on the elliptical machine and all was fine. To try and force high HR I loosened the watch MUCH more than I'd normally wear and sure enough it spiked to 150-160 when it was actually around 120.  I tightened the watch back up and the HR remained crazy high despite being tightened to my wrist.  While I continued my elliptical workout I stopped and saved the cardio app and switched over to the elliptical app and almost immediately the HR was normal range again.

I can't implore to this group enough, if you have the issue you MUST open a ticket with Garmin.  They don't work problems based on what's in the forum.  It was kind of a pain because I had to plug the watch into the PC, load a huge folder to my PC which took about 45 mins, then had to delete IMG and Map files, then zip the file and then email it to Garmin with the ticket ID they provided me.   https://support.garmin.com/en-US/ql/?focus=topics

Andy_ROC said:

Anyway I've only seen the high HR spike when I'm on the elliptical and I'm using the cardio app, not with the elliptical app

As crazy as it sounds, this is by design. This is from their website:

Additionally, heart rate is calculated differently for each activity type. Make sure you use the activity type that matches the activity being done. For example, using the Elliptical app while running outdoors could result in incorrect HR being recorded. 

I've just bought a Fenix 6 Pro and it's updated from 11.xx to 15.20.

The heart rate sensor is a shocker - it's abysmal. I am coming to the 6 Pro via a Forerunner 245 (lovely and accurate) and a Fenix 5 Plus both of which were very accurate at least resting and generally for low level activity.

With a 6 Pro on one wrist and the 245 on the other, I'm seeing the Fenix 6 Pro spike to 120-135 BPM just walking into my kitchen (my 245 reports about 65 BPM which is correct) - the 6 Pro is nuts, my running HR is less than what the 6 Pro reports just moving about my house.

Annoying it seemed to be fine before the 'upgrade' - honestly these untested firmware updates feel like corporate vandalism. Crazy a low end 245 costing £300 less than the 6 Pro outperforms it in HR accuracy.

Indeed. i also had a 245 and it was great. a month ago i bought a 6 pro to try the wohr and to my surprise it as good as the 245. no complaints. It came with 12.20 and i have not updated yet as everything i use works and the new features at this time do not interest me. Try to downgrade to 12.20 and see if you get better results. A year ago i had try a 6S and had to return it as the wohr was awful.

Thank you for that info.  I could understand outdoor run v elliptical being wrong for various reasons. But elliptical vs cardio doesn't make a lot of sense for being error prone.  For me it seems like a basic ask to allow cardio app to be used on elliptical then allowing me to transition to jumping jacks, burpees, pushups, mountain climbers, crunches etc. --- none the less thank you again for the info.

Open a ticket with Garmin please.

curious if they say that just to kick the can down the road.  impossible they are unaware of this problem as any of their employees wearing a watch would see.  My resting heart rate on the new code is much higher so anyone would notice this with or without exercise.  

Interesting about your RHR.  I've noticed no issues with resting HR--- all completely normal.  I'll be sure to keep the board updated on my ticket, but please others need to submit a ticket. Go the Chat in their customer service area and they will open ticket and collect info.

Resting for me is +/-5 of my heart rate belt - on my phone I can run two apps on the screen, so I have Garmin Connect and Wahoo Utility connected to a external belt simultaneously so I can see both in realtime.

I have no idea if or how Garmin tests changes - you would think they had a pool of people with known heart rates all all wearing external belts so they could track their changes to measure the impacts but I suspect they don't do this. Inevitably some changes will break things for some people and fix things for others. Trouble is, any change that fixes our problems will break things for other people, so they will raise a ticket too, and so the cycle continues.