OHR incorrect measurement.

I've got the same issue more and more frequently too. I mainly use the watch while cycling workout as a HR sensor connected to my Garmin Edge 130 Plus. So basically my watch broadcast HR over Bluetooth (I guess). But the problem has nothing to do with the fact that HR is broadcasted. When hiking, I use my watch to record the activity and I've got the same incorrect HR problem. 

Basically HR would remain much lower than what it actually is, for 20 minutes, sometimes 40 minutes and then suddenly jumps to the correct (I presume) HR. I know the HR is incorrect by just putting one finger on my carotid (Watch: 80, Estimated HR on Carotid: >>> 120). 

I paid 449 € for a watch that's got an OHR sensor that doesn't work.

My watch tells me I climbed the first 600 meters in 45 minutes with an HR below 100.

I wish I could actually do that but my HR was above 150 for at least 30 minutes.

Please HELP !!!!!

The sensor works fine, the software is the issue. My OHR worked perfect for interval training with very short intervals until firmware version 17.x came out. Even the Fenix and Epix watch seem to suffer. Version 18.x and 19.x seem to use a low-pass filter (using some moving/weighted average) so the OHR doesn't behave erraticely/bumpy but on the other hand, on a change in heart rate one has to wait a long time to get this change reflected in the sensor reading

There are a couple of ways to get Garmin to take the issue more seriously:
- going public with it (not YET preferred)

- request a replacement (you might get a refurbished one)

- send in a support ticket; this would in fact be the most useful option, especially if you had good behaviour in previous firmware versions so Garmin can analyze it and the final solution is hopefully better due to all our data

It seems that although many posts have been made, the issue is still not addressed properly although there have been ocmments in the forum that a fix is underway.

Let's HOPE and PRAY that Garmin

Yep, 17.xx worked better. Is there a way to downgrade?

Garmin-Sierra

I bought the forerunner 955 solar because my previous Garmin watch had issue with the HR... it was an old Vivoactive 3 which used to work fine and progressively started to have issues with the HR. I guess what happened is that the Vivoactive 3 got upgraded too ! (BTW, I confirm now that my Vivoactive 3 had the same problem, over time).

What a mess; I really like Garmin products, the ecosystem, its consistent integration, despite the high prices, but I am really expecting products that just work as planned.

GARMIN please fix it quickly, or at least offer an option to switch back to before the "low-pass filter".

17.x was better but it had spikes, 16 worked flawless.

Did a quicker run for the first time in a long while without my chest strap. Made sure my watch was tight enough on the wrist, took a good 5+mins before it got to reasonably accurate reading, stayed good for another 15 odd mins, and then dropped as I sped up, even more so during a sprint finish.

Considering so many of the watch and garmin metrics are aligned with HR measurements, having such a poor OHR makes these metrics useless over the long term and pointless in the short term, considering after the above run, my watch thought I had got dramatically fitter.   

I sometimes have the opposite problem on my FR955 Solar, extremely high readings with HR at 170bpm for 10-15 minutes when just mowing my lawn.. I have to restart my watch to get correct readings again (around 80bpm).

Are running the 19.18 software and my watch is brand new (two weeks old).

It seems like you have some serious software issues Garmin-Sierra

For comparison, today's strap worn run, versus yesterday's no strap run and the day before's interval run with a chest strap 

Same problem today...

I am going for a refund; this watch is, unfortunately, an unreliable HR sensor.