955 Heart Rate Issue - Does it happen on other models?

I'm not disagreeing with your assessment that there is an issue with the 955's OHR, however, all watch OHRs struggle in colder weather. This is due to the fact that your body is adjusting to the cold by directing blood flow away from the extremities (hand and wrist) to help maintain your core temperature. Less blood flow means less reflection for the optical sensor to "see." As you warm up through exercise, blood flow may increase and the OHR has a better chance to lock on.

Of the many watch models I've used from all different manufacturers, none has been reliable in cold weather. The only solution is one you've probably already heard: an external HR monitor. Chest straps worked great, but they also need moisture to work well (pre-wetting or sweat as it builds up), so they can struggle in cold, dry climates. Perhaps the most reliable is an optical HR monitor that can be placed higher up the arm. I use a Polar Verity Sense placed high on the tricep throughout the winter months.

Another option may be to do a short warm up indoors to get the blood flowing before heading out on your run. Jumping jacks, push-ups, or just running in place would be enough to spike your HR. You could confirm the 955 has an HR lock by observing it on a data screen before starting your activity.

The OHR issues mentioned in this thread are NOT warming up related. Tests with Garmin Elevate V5 sensor shows a correct OHR measurement. While watches with the Elevate V4 sensor shows incorrect heart rates.

Tested with multiple runs, a Elevate V4 watch in the left wrist and a Elevate V5 watch on the right wrist.

Elevate is the sensor used in the Garmin watches. This OHR issues seems to exist on ALL Elevate V4 watches. 

V5 is, IMHO, 10% better than V4. But it depends on your use case. You can see a nice comparison if you search YouTube with the words "Fenix 7 pro quantified scientist." The links don't work, you know.

Thanks I appreciate the response. 

I feel like i am willing to live with the known limitations of the wrist heart rate technology but it does seem like this issue is outside of that.   The person from garmin that I spoke with about this stated that there is a known software issue that is driving this problem. 

The run that prompted me to write my post showed the garmin not connecting to my heart rate for over 30 minutes.  It was around 50 degrees out so while it was cooler it was not that cold.  I also followed the advice of the person from Gramin that I spoke with and went to the gps lock screen for over 5 minutes before starting. 

I dont really know though if this is just how it is or if I could do better with a different model watch.  I do really enjoy the data and it feels frustrating that it is so off. 

My wife has a FR255 and she has the exact same issue. It has bugged her so much she even bought a chest strap, which should NOT be required for a watch that is usually recommended for having a very accurate wrist HR monitor.

I actually wanted to start a similar threat to bring the issue under attention once again because this weekend it took 17 WHOLE MINUTES, well into my Tempo run for my HR to FINALLY start registering properly.

@Garmin, please let me give you some logs and debug files so you can actually look into the issue because this is just insane and has been plaguing the watch for a very long time now.

That does sound frustrating. It probably isn't a weather issue if it's occurring at 50+ degrees. 

I've actually been pleasantly surprised with the 955's OHR recently. It is not my current everyday watch, but I do still wear it for most runs as a reference. I am on the beta software, though, version 21.16. It looks the WHR got a bump up from 17.00.09 to 18.01.04.

So maybe there's hope Garmin has been working on it? I don't see much discussion about inaccurate HR in the beta forum.

Thanks for this.  It seems that the Fenix 7 pro has the elevate 5 sensor, though other people in this thread have mentioned that the issue persists in the Fenix 7 pro but I'm not completely clear.  The fenix forum page doesnt have a clear issue thread like the 955 page so it is hard to tell. 

I'm not proud to admit it but I would be willing to dump my 955 just to get away from this and watch for a 7 pro sale just so I can move on without having to figure out how to install old firmware (Which I appreciate that people are being so clear about, I just have very limited time and energy to put into that). 

It seems accurate within the limitations of the technology most of the time, and this issue only happens something like 30% of the time for me.  It weirdly seems to go through cycles where it is a bit worse, and then it seems to back off for a while and it is in a worse cycle right now as it has happened every run the last 5 or so.  But I have had many normal runs.. everything from half marathons, to 8 mile trail runs where I have had a map running, intervals have been mostly fine.. I really like the watch. 

I also do a lot of runs where I am trying to stay in "base" or "revcovery" mode and want to stay in zone 3, whcih I can tell by nasal breathing too, but I like to see it on the watch too (which is one of the reasons I bought it).  Seeing the heart rate sit at 115 while I am going up a hill wanting to stay in zone 3 is driving me batty. 

I have same issues every time I need to use optical sensor instead of my hrm belt which makes various intervals and other hr based trainings simply impossible to do :( I used Apple Watches, Suunto etc in past and hr data from sensor was always more or less accurate with hr belt, there was some latency of course, but it was comparable, Garmin has many more features I use, but in terms of HR sensor it is useless in running.

Hello,

I'm using firmware 15.19 and it works quite well with the heart rate. However, I would also like to have the new functions that I am missing. It's a real shame that Garmin doesn't offer a solution for all watches with the elevate 4 sensor. Why don't they go back to the 15.19 version of the sensor? Technically it is possible...

The Forerunner 945 still works great with the elevate 3 sensor.

Garmin, what are you doing?

And the second point is the new Garmin Connect App, Nobody like this new App. Garmin, why do you ignore it?

BR